Startseite Diffusion law of sulfate ions in coral aggregate seawater concrete in the marine environment
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Diffusion law of sulfate ions in coral aggregate seawater concrete in the marine environment

  • Hao Shi , Qing Wu , RongRong Yin EMAIL logo , Muhammad Akbar , Ning Yang , Jianbing Mo und Jianming Yang
Veröffentlicht/Copyright: 21. Juni 2024
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High Temperature Materials and Processes
Aus der Zeitschrift High Temperature Materials and Processes Band 43 Heft 1

Abstract

To investigate the diffusion of sulfate ions in coral seawater concrete under the mechanism of the wetting–drying cycle of sulfate solution, the concentration of sulfate ions in coral concrete at different depths under different cycling cycles was tested in this experiment. Finite-element numerical simulations were then carried out using COMSOL software. The results showed that the sulfate ion concentration in the concrete at the same depth increased steadily with time, and the erosion depth also increased. The numerical simulations successfully reproduced the diffusion of sulfate ions in coral seawater concrete under the mechanism of the wetting–drying cycle of sulfate solutions.

Keywords: coral aggregate seawater concrete (CASC); wetting–drying cycle; law of sulfate ion diffusion; COMSOL

1 Introduction

The rational use of marine resources is a key issue in realizing sustainable development. Countries continue to accelerate marine infrastructure construction projects to develop marine resources effectively. Concrete is the basic material used to support infrastructure construction. Traditional construction materials such as land-based gravel, fresh water, and river sand face challenges such as high transportation costs and vulnerability to complex marine climates, which greatly affect the economy and sustainability of the projects [1,2,3]. Therefore, there is an urgent need for a more viable and economical alternative material. The United States was the first country to use coral aggregate concrete in civil engineering practice, and during the Second World War, it was widely used in the construction of roads, airports, and other infrastructure in the islands of the Western Pacific, some of which are still in regular use today [4]. The US civil engineering standard "Unified Facilities Criteria-Tropical Engineering" specifies that coral aggregates should be used to mix concrete when conventional aggregates are scarce [5]. The coral islands and reefs in the South China Sea area are rich in coral debris, so on the premise of not destroying the local ecological environment, the coral debris obtained from cleaning the waterways can be used as concrete aggregate after washing, crushing, screening, and other processes [6]. For island projects far from the mainland, coral debris and coral sand can be used as coarse and fine aggregates, mixed with cement, admixtures, mineral admixtures, and seawater in a certain proportion to formulate full coral aggregate seawater concrete (CASC) [7], which can not only greatly improve the construction efficiency of marine infrastructure construction and reduce the cost of the project, but also has good ecological compatibility.

Coral aggregate is a porous material [8], and its natural defects can adversely affect the durability of coral aggregate concrete. In seawater, SO 4 2 − is the second largest constituent ion after Cl − in terms of ion concentration. The destructive process of sulfate erosion is a complex process of physical and mechanical changes in which erosion ions enter the concrete through diffusion and capillary adsorption, react with cement hydration products, generate expansion substances, and lead to concrete cracking. This allows more erosion ions to enter the concrete, causing a decrease in the durability and safety of the concrete structure [9]. Additionally, sulfate attack leads to the decalcification reaction of hydrated calcium silicate, forming a paste in the cement matrix, decreasing the cementing capacity, and causing cracking and deterioration of the concrete material [10,11]. Wattanachai et al. [12] found that chloride salts in coral aggregates resulted in more severe steel corrosion in coral concrete than in ordinary concrete (OPC) at the same mix ratio. Huang et al. [13] found that the chloride concentration of coral concrete was higher than that of ordinary concrete. Li et al. [14] found that concrete made with sulfate aluminate cementitious materials had higher resistance to seawater and sulfate erosion. Tang et al. [15] found similar findings in sulfate erosion studies, where coral concrete showed similar strength loss under sulfate erosion as ordinary concrete but less loss of modulus of elasticity with more long-term sulfate intake. Wang et al. [7] investigated the deterioration process of coral concrete under a combined sulfate-chloride attack.

After these studies, few researchers have studied the durability of CASC under the combined effects of sulfate and the wetting–drying cycles. In this article, we test the distribution of SO 4 2 − inside coral concrete under the erosive action of sulfate and the wetting–drying cycles by simulating the actual environment in the tidal zone of the ocean. At the same time, we establish the apparent diffusion model of SO 4 2 − by using test data from coral concrete and numerically simulate the diffusion of SO 4 2 − on coral concrete specimens through the finite-element software COMSOL. We compare and analyze the simulation results with the actual measured test results. This experimental study is highly significant for applying coral concrete in the marine tidal zone, providing fundamental data for technical engineering practices and smoothly promoting various types of infrastructures, such as coasts and wharf construction.

2 Experimental program

2.1 Test materials

2.1.1 Cement

The cement selected for this experiment is P·O42.5 ordinary Portland cement produced by Jiangsu Helin Cement Co., Ltd. The basic performance indicators of the cement are shown in Table 1.

Table 1

Physical and mechanical properties of cement

Density (g·cm−3) Condensation time (min) Flexural strength (MPa) Compressive strength (MPa)
3.10 Condensation Congeal 3 days 28 days 3 days 28 days
185 250 5.2 8.8 25 50.5

2.1.2 Water

The seawater used for mixing coral concrete is artificially prepared seawater. Due to the varying compositions of seawater in different coastal ports in China (as shown in Table 2), a standardized artificial seawater composition was used in this experiment to avoid any impact on the analysis of experimental results caused by inconsistencies in seawater ratios. The composition of seawater used in this article is shown in Table 3 [16].

Table 2

Chemical components of the seawater near the harbors of China

Name of seaport Seawater chemical composition (mg·L−1) Total salt (mg·L−1) PH
SO 4 2 ‒ Mg2+ Cl‒ Ca2+
Dalian 2,171 1,102 15,900 408 28,729 8.5
Qinhuangdao 2,372 1,174 17,339 378 31,330 7.9
Tianjin 2,489 1,156 16,842 482 30,420 7.9
Penglai 2,167 1,093 15,775 384 28,503 8.4
Yantai 2,463 1,050 15,450 437 28,620 7.0
Qingdao 2,400 1,445 16,000 — 29,040 8.0
Lianyungang 2,289 1,159 10,700 397 30,173 8.0
Beilun 168 803 11,760 258 21,250 8.0
Xiamen 2,140 1,172 15,440 — — 8.0
Table 3

Chemical composition of artificial seawater

Name (of a thing) Molecular formula Mass (mg·L−1)
Common salt NaCl 46,934
Magnesium chloride MgCl2 9,962
Sodium sulfate Na2SO4 7,834
Calcium chloride CaCl2 2,204
Dicalcium phosphate KCl 1,328

2.1.3 Water-reducing agents

This test's water-reducing agent is a high-efficiency polycarboxylic acid water-reducing agent manufactured by Jiangsu Subot. The water-reducing agent has a net slurry flow of 240 mm, a net slurry flow of 210 mm after 1 h, a solid content of 20.1%, an initial setting time difference of 120 min, a shrinkage ratio of 110%, a chloride ion content of 0.013%, a water secretion ratio of 55.5%, and a sodium sulfate content of 0.2%.

2.1.4 Coarse/fine aggregates

Coarse aggregate: A South China Sea island reef was selected as the source for the coarse aggregate, located near a group of dead reef-building coral. The outer surface of the coral is uneven, with a uniform distribution of apertures of varying sizes. The coral coarse aggregate primarily consists of long rods, antlers, and flakes, as illustrated in Figure 1. Because natural corals come in different shapes and sizes, the coral aggregate was crushed and sieved before mixing the concrete. The grading curves of the coral coarse aggregate before and after crushing are shown in Figure 2(a), and the basic physical property parameters of the aggregate are shown in Tables 4 and 5.

Figure 1 Coral reef and coral sand.
Figure 1

Coral reef and coral sand.

Figure 2 Grading curve of coral coarse aggregate and coral sand before and after crushing: (a) comparison of grading curves of coral coarse aggregate before and after crushing and (b) coral sand grading curve.
Figure 2

Grading curve of coral coarse aggregate and coral sand before and after crushing: (a) comparison of grading curves of coral coarse aggregate before and after crushing and (b) coral sand grading curve.

Table 4

Physical properties of coral coarse aggregate

Apparent density (kg·m−3) Bulk density (kg·m−3) Fineness modulus Porosity (%) Natural moisture content (%) 1 h water absorption (%) Mud content (%)
2,450 1,163 2.6 48 0.3 13.1 0.58
Table 5

Physical properties of coral coarse aggregate

Apparent density (kg·m−3) Bulk density (kg·m−3) Cylinder pressure strength (MPa) Porosity(%) Natural water content (%) 1 h water absorption rate (%) Mud content (%)
1,865 928 1.6 55 0.1 17.1 0.58

The grading curves and upper and lower limits of the coral sand are shown in Figure 2(b).

2.2 Specimen preparation

2.2.1 Concrete mix ratio

The strength grade of concrete used in the specimens was designed according to C30. According to the preparation of the CASC mix proportion experiment in the early stage, the mix proportion with the best durability was selected, as shown in Table 6.

Table 6

Coral concrete mix design

Serial number Water–cement ratio Cement (kg·m−3) Water (kg·m−3) Coral fine aggregate (kg·m−3) Coral coarse aggregate (kg·m−3) Water reducer (%)
C30 0.35 557 195 749 749 0.2

This report specifies the coral concrete target strength grade as C30. Due to the porous qualities of the coral aggregate, it exhibits a high water absorption rate, which requires an increase in the amount of additional water used during the mixing process. The formula to calculate the additional water consumption is as follows: additional water consumption = 8% of the total coral fine aggregate and coral coarse aggregate mass. Moreover, the water-reducing agent used is based on the percentage of the cement mass.

2.2.2 Preparation of specimens

Following the relevant provisions of SL 352-2006 “Test Procedures for Hydraulic Concrete” and GB/T 5008-2009 “Test Methods for Long-Term Properties and Durability of Ordinary Concrete” standard, coral concrete specimens selected for this test were cubes with 100 mm × 100 mm × 100 mm edges. Due to the porous nature of coral aggregate, it has high water absorption, and the mixing process in this test adopted the second feeding method, which is better than traditional mixing [17]. The strength of coral aggregate is relatively low, and its density is extremely low, which makes it easy to float in the mix. This results in poor uniformity of concrete, causing insufficient overall strength. Mostly antler-shaped, the irregular shape of coral aggregate makes vibration more difficult. The specific mixing process is

  1. In the initial stage of adding coarse and fine aggregates, incorporate the aggregates along with a measured amount of water ( W 1 ), and mix for 10 s. Figure 3 shows the flow diagram depicting the mixing process before and after the enhancement.

  2. Add cement and mix for 45 s.

  3. Add the remaining water ( W 2 ) and admixture, mix for 45 s and discharge W 2 = W all − W 1 .

Figure 3 Before and after improvement of the mixing process.
Figure 3

Before and after improvement of the mixing process.

Once the mixing process is finished, the concrete is poured into the test mold in two separate phases and vibrated twice. The first time, the first 1/2 of the concrete is added and vibrated on the vibrating table for about 20 s, depending on the actual situation; this is to avoid the phenomenon of floating aggregate. Then, the second time, the remaining 1/2 of the concrete is loaded and vibrated on the vibrating table for about 30 s. To ensure an even distribution of the aggregates within the mold, reinforcing bars are constantly inserted and pounded during the vibration process. Once the vibration is complete, the specimen is placed on a flat surface, and after one hour, the surface of the specimen is manually smoothed to achieve a proper finish.

2.3 Test methods

After 24 h of molding, the specimens were de-molded and placed in a standard concrete curing room at 20°C ± 2°C and a humidity of not less than 95% for 28 days. Sulfate erosion experiments were conducted in alternating the wetting–drying environments using a 5% sodium sulfate solution as the erosive agent. To ensure consistent conditions, five surfaces of each specimen were sealed with epoxy resin, leaving only one surface exposed to sulfate ions. The cycle time was two days each, the ratio of drying time to soaking time was 1:1, and the oven temperature was maintained at 60°C. The sulfate ion content of the concrete was determined by chemical titration. The method of determination was adopted by drilling samples and improved barium sulfate weight method [18].

3 Test results and discussion

3.1 Determination of sulfate ion concentration

The mass fraction was determined using the methodology above, with each sample taken 5 mm apart and the deepest sample 21 mm. Figure 4 depicts the internal concentration distribution of SO 4 2 − in coral concrete under the wetting–drying cycle of sulfate solution. The concentration of SO 4 2 − decreases with increasing depth, while the concentration of SO 4 2 − at the same depth increases with erosion time. SO 4 2 − does not diffuse from the surface to the coral concrete interior due to the concentration gradient. Instead, it enters the interior and participates in chemical reactions to form precipitates, causing a decrease in the depth of SO 4 2 − concentration buildup. However, with extended erosion time, SO 4 2 − and the reaction products accumulate, which induces microcrack expansion in the coral concrete. During the wetting–drying cycle, sulfate enters the concrete's interior through diffusion and capillary adsorption. In the dry stage, rapid evaporation inside the coral concrete leads to SO 4 2 − residues staying in the coral concrete. With the increasing number of cycles, the concentration of sulfate solution inside the coral concrete saturates, resulting in the crystallization precipitation of sodium sulfate decahydrate ( Na 2 SO 4 ·  10H 2 O ), which leads to expansion stress and the propagation of cracks within the coral concrete. Consequently, SO 4 2 − channels inside the coral concrete widen, thus accelerating the diffusion of SO 4 2 − and ultimately leading to a continuous increase in the concentration of SO 4 2 − .

Figure 4 Concentration distribution of sulfate ion under different immersion times.
Figure 4

Concentration distribution of sulfate ion under different immersion times.

3.2 Theoretical models

3.2.1 Theoretical models

Fick's law of diffusion can be applied to model the diffusion of ions in concrete when it is saturated. However, concrete specimens are often in an unsaturated state, and the destruction caused by the dissolution of sodium sulfate crystals is more severe than that caused by erosion. When concrete is wetted, anhydrous sodium sulfate crystals dissolve and form a saturated sodium sulfate solution. This also leads to the formation of numerous crystals, which applies considerable crystallization pressure on the pores of the concrete and results in their destruction. Therefore, the purpose of this article is to investigate the transport law of sulfate ions inside concrete under the wetting–drying cycle mechanism, which necessitates a modification of the traditional Fick's law of diffusion.

Licong [19] derived the formula for the diffusion coefficient of sulfate ions in concrete pore solution, which is used to calculate the sulfate ion transfer coefficient

(1) D s = 3.0 × 10 − 11 ξ − 2.4 × 0 − 17 ξ ⋅ c ( 1.3 × 10 6 ⋅ η − 2400 + I ) ,

(2) I = 220 + 2 c ,

(3) η = 0.6 4 I ( 1 + 0.0268 I ) 2 ,

(4) ξ = 17.5 + c ,

where c is the concentration of concrete sulfate ions and k is the chemical reaction rate constant.

In this article, only the transport during the immersion phase SO 4 2 − is considered, and the main effects produced by the wetting–drying cycle on the concrete are limited to changes in porosity and diffusion coefficients, which leads to the following simplification of Fick's second law equation:

(5) ∂ c ∂ t = ∇ D s ∇ c + k ⋅ C ca 2+ ⋅ c ,

where C Ca 2 + is the calcium ion concentration, D s is the diffusion coefficient in pore solution, t is the age of erosion.

As the theoretical model takes the form of partial differential equations, solving the problem is highly complex, and finding a unique analytical solution through purely mathematical calculations is impractical. Therefore, numerical solutions are obtained using conventional methods such as the finite-element difference and finite-element method. In this study, numerical solutions were acquired via finite-element software, explicitly employing the finite-element method for calculations.

3.3 Numerical simulation

3.3.1 Random aggregates

To ensure the randomness of the simulated aggregate concerning plane position, particle size, and shape, this study has employed the Monte Carlo method [20,21]. Also known as statistical simulation methods, this approach is a crucial class of numerical computational methods guided by the statistical theory of probability, which utilizes random numbers (or pseudorandom numbers) to solve numerous computational problems. With the assistance of a specific stochastic process to describe repeated statistical experiments, the Monte Carlo method can satisfy any given division of the proviso combinatorial and solve various problems in physical mathematics. The Monte Carlo method is applied to simulate random variables, and the most fundamental random variable is a set of uniformly distributed random variables within the interval [0,1] and corresponding density function:

(6) f ( x ) = 1 , x ∈ [ 0 , 1 ] 0 , x ∉ [ 0 , 1 ] .

The distribution function is

(7) F ( x ) = 0 , x < 0 x , 0 ≤ x ≤ 1 1 , x > 1 .

In this article, the Matlab software is utilized to randomly generate coral aggregates, whereby polygonal shapes are preferred due to the wide variety of natural coral shapes. Current numerical simulations predominantly use circular, elliptical, and polygonal shapes. Presently, there are two methods for randomly generating polygonal aggregates – the aggregate base random extension and the random point method [22]. The former involves creating polygons on randomly generated triangles or quadrilaterals while considering the concavity and convexity to prevent sharp corners. However, this method is mathematically complex, time-consuming, and challenging to judge polygon concavity.

On the other hand, the random point method involves generating a circular or elliptical base and randomizing points at the aggregate base boundary or inside to yield polygonal aggregates of varying numbers of sides. This method is much quicker and more straightforward as there is no need to consider concavity and convexity. However, the polygons generated may often have sharp, acute corners. This article employs the random point-taking method for a more accurate simulation of polygonal aggregate generation.

3.3.2 Model creation

This article employs COMSOL Multiphysics, a multi-physics field coupling finite-element software, for two-dimensional planar simulation. The model is of a specific size, with sulfate ions penetrating the concrete from the left face. The other three surfaces are designated as free surfaces with no sulfate ion infiltration, as illustrated in Figure 5. Throughout the erosion process, the concentration of sulfate solution remains constant as a given value. Table 7 outlines the parameters required to simulate the sulfate’s wetting–drying cycle.

Figure 5 Schematic diagram of finite-element model.
Figure 5

Schematic diagram of finite-element model.

Table 7

Main parameters of the model

Notation Numerical value Descriptive
D s 1 .7 × 10 ‒ 11 m 2 /s SO 4 2 ‒ Diffusion coefficient in the pore solution
W 1.28 Adjustment factor
α 0.6651 Degree of cement hydration
V a 35% Coarse aggregate volume fraction
k 3.05 × 10 ‒ 8 m 3 · mol ‒ 1 · s chemical reaction rate
C Ca 2 + 21.25 mol·m‒3 Calcium ion concentration in concrete pore solution
T 298.15 K Environmental temperature
C 1 944 mol·m‒3 Mass fraction of sodium sulfate solution

The finite-element model boundary conditions are:

Left: C ( 0 , t ) = C 0

Internal initial value: C ( 0 , t ) = C 0

The boundary conditions for the other three sides are: C ( x , 0 ) = 0 .

To simplify the calculation process, a cycle regime of one day has been selected for this section. The drying–wetting ratio has also been set to 1:1.

Once the model is created, interface properties define the material properties. The cross-section is then meshed, and the time unit and time step are determined to calculate the graph of sulfate concentration over time at a given location or moment in time (Figure 6).

Figure 6 Mesh generation of finite-element model.
Figure 6

Mesh generation of finite-element model.

3.3.3 Numerical simulation analysis

The rationality of the model is verified by comparing the numerical simulation results with the experimental results. As illustrated in Figure 7, the experimental results of the depth of erosion of coral concrete subject to the wetting–drying cycle of 5% sodium sulfate solution are shown to be in good agreement with the numerical simulation results. This indicates that the model used for the numerical simulation is reasonable for simulating at the microscopic level.

Figure 7 Schematic diagram of finite-element model: (a) 30 cycles and (b) 120 cycles.
Figure 7

Schematic diagram of finite-element model: (a) 30 cycles and (b) 120 cycles.

Figure 8 presents the distribution of sulfate ions in the specimen after 30 and 120 wetting–drying cycles. It can be observed that in the early stage of erosion, sulfate ions are mainly concentrated on the surface of the specimen. Analysis of the contour lines reveals that the center part is essentially flat, indicating that sulfate ions do not erode the interior of the concrete. The edge of the concrete is directly exposed to the sulfate solution, through which sulfate ions enter the concrete by free diffusion and undergo a chemical reaction with the concrete's hydration products. The reaction products consume the hydration products of the surface layer of the concrete, creating expansion stress on the pores and causing the surface layer to crack. Late in the cycle, through the cracks in the surface layer, more sulfate ions enter into the next layer of concrete.

Figure 8 Height expression of sulfate ion distribution: (a) 30 cycles and (b) 120 cycles.
Figure 8

Height expression of sulfate ion distribution: (a) 30 cycles and (b) 120 cycles.

Up to 30 cycles and 120 cycles, Figure 9 displays the distribution of sulfate ions in the specimen. Comparison of Figure 9(a) and (b) after 30 cycles and 120 cycles shows that the latter has a broader distribution of sulfate ions and a higher concentration of sulfate ions at the edges of the specimen. The center of the specimen remained planar, indicating incomplete delivery of sulfate ions after 120 wetting–drying cycles. Additionally, sulfate ion concentration increased significantly with increasing cycles. These findings highlight the importance of carefully considering test time and sample preparation to ensure accurate and reliable experimental results. In conclusion, the authority of the test equally improved with the increasing number of cycles, providing strong support for academic research in relevant fields.

Figure 9 Sulfate ion distribution map: (a) 30 cycles and (b) 120 cycles.
Figure 9

Sulfate ion distribution map: (a) 30 cycles and (b) 120 cycles.

4 Conclusion

This study aimed to compare the distribution of sulfate ions in CASC with different cycle times and simulate their diffusion using COMSOL. The study revealed the following conclusions:

  1. A simplified Fick’s second law formula was established to consider only sulfate ion transfer under the wetting–drying cycle of sulfate solutions.

  2. The diffusion of sulfate ions in concrete under the wetting–drying cycles follows Fick’s second law of diffusion. The content of sulfate ions increased continuously as the number of cycles increased and the erosion depth deepened. After 120 wetting–drying cycles, the sulfate ions were still not fully transferred to the concrete center.

  3. The COMSOL simulation calculations based on the apparent diffusion model of sulfate ions strongly correlated with the test results and had a small calculation error; the numerical data curve matched the test data. Experiments and simulations help to understand the process of sulfate ion diffusion in coral concrete in the dry and wet cyclic erosive environments of sulfate solutions and practical engineering applications.

  1. Funding information: This study was financially supported by Jiangsu University (High-tech Ship) Collaborative Innovation Centre Self-cultivation Project (XTCX202410), the National Natural Science Foundation’s “Study on Interface Behaviour Regulating Mechanism of Coating/Steel System Based on MPC in Severe Marine Environment” (52378265), “Postgraduate Research & Practice Innovation Program of Jiangsu Province”, “Investigation on Durability Test and Prediction Model of Coral Concrete under Complex Environment” (SJCX24 2553).

  2. Author contributions: Hao Shi: Conceptualization, Methodology, Validation, Investigation, Data curation, Writing – original draft, Writing – review & editing. Qing Wu: Conceptualization, Methodology, Supervision, Resources, Funding acquisition, Writing – review & editing. Rongrong Yin: Supervision, Resources, Funding acquisition. Hao Wang: Methodology, Validation, Investigation, Data curation. Muhammad Akbar: English support. Ning Yang: Investigation. Jianbing Mo: Modification help, Funding acquisition. Jianming Yang: Modification help, Funding acquisition.

  3. Conflict of interest: Authors state no conflict of interest.

  4. Data availability statement: The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.

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Received: 2024-04-07
Revised: 2024-05-13
Accepted: 2024-05-25
Published Online: 2024-06-21

© 2024 the author(s), published by De Gruyter

This work is licensed under the Creative Commons Attribution 4.0 International License.

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  19. Characterization of low-damage cutting of alfalfa stalks by self-sharpening cutters made of gradient materials
  20. Thermo-mechanical effects and microstructural evolution-coupled numerical simulation on the hot forming processes of superalloy turbine disk
  21. Endpoint prediction of BOF steelmaking based on state-of-the-art machine learning and deep learning algorithms
  22. Effect of calcium treatment on inclusions in 38CrMoAl high aluminum steel
  23. Effect of isothermal transformation temperature on the microstructure, precipitation behavior, and mechanical properties of anti-seismic rebar
  24. Evolution of residual stress and microstructure of 2205 duplex stainless steel welded joints during different post-weld heat treatment
  25. Effect of heating process on the corrosion resistance of zinc iron alloy coatings
  26. BOF steelmaking endpoint carbon content and temperature soft sensor model based on supervised weighted local structure preserving projection
  27. Innovative approaches to enhancing crack repair: Performance optimization of biopolymer-infused CXT
  28. Structural and electrochromic property control of WO3 films through fine-tuning of film-forming parameters
  29. Influence of non-linear thermal radiation on the dynamics of homogeneous and heterogeneous chemical reactions between the cone and the disk
  30. Thermodynamic modeling of stacking fault energy in Fe–Mn–C austenitic steels
  31. Research on the influence of cemented carbide micro-textured structure on tribological properties
  32. Performance evaluation of fly ash-lime-gypsum-quarry dust (FALGQ) bricks for sustainable construction
  33. First-principles study on the interfacial interactions between h-BN and Si3N4
  34. Analysis of carbon emission reduction capacity of hydrogen-rich oxygen blast furnace based on renewable energy hydrogen production
  35. Just-in-time updated DBN BOF steel-making soft sensor model based on dense connectivity of key features
  36. Effect of tempering temperature on the microstructure and mechanical properties of Q125 shale gas casing steel
  37. Review Articles
  38. A review of emerging trends in Laves phase research: Bibliometric analysis and visualization
  39. Effect of bottom stirring on bath mixing and transfer behavior during scrap melting in BOF steelmaking: A review
  40. High-temperature antioxidant silicate coating of low-density Nb–Ti–Al alloy: A review
  41. Communications
  42. Experimental investigation on the deterioration of the physical and mechanical properties of autoclaved aerated concrete at elevated temperatures
  43. Damage evaluation of the austenitic heat-resistance steel subjected to creep by using Kikuchi pattern parameters
  44. Topical Issue on Focus of Hot Deformation of Metaland High Entropy Alloys - Part II
  45. Synthesis of aluminium (Al) and alumina (Al2O3)-based graded material by gravity casting
  46. Experimental investigation into machining performance of magnesium alloy AZ91D under dry, minimum quantity lubrication, and nano minimum quantity lubrication environments
  47. Numerical simulation of temperature distribution and residual stress in TIG welding of stainless-steel single-pass flange butt joint using finite element analysis
  48. Special Issue on A Deep Dive into Machining and Welding Advancements - Part I
  49. Electro-thermal performance evaluation of a prismatic battery pack for an electric vehicle
  50. Experimental analysis and optimization of machining parameters for Nitinol alloy: A Taguchi and multi-attribute decision-making approach
  51. Experimental and numerical analysis of temperature distributions in SA 387 pressure vessel steel during submerged arc welding
  52. Optimization of process parameters in plasma arc cutting of commercial-grade aluminium plate
  53. Multi-response optimization of friction stir welding using fuzzy-grey system
  54. Mechanical and micro-structural studies of pulsed and constant current TIG weldments of super duplex stainless steels and Austenitic stainless steels
  55. Stretch-forming characteristics of austenitic material stainless steel 304 at hot working temperatures
  56. Work hardening and X-ray diffraction studies on ASS 304 at high temperatures
  57. Study of phase equilibrium of refractory high-entropy alloys using the atomic size difference concept for turbine blade applications
  58. A novel intelligent tool wear monitoring system in ball end milling of Ti6Al4V alloy using artificial neural network
  59. A hybrid approach for the machinability analysis of Incoloy 825 using the entropy-MOORA method
  60. Special Issue on Recent Developments in 3D Printed Carbon Materials - Part II
  61. Innovations for sustainable chemical manufacturing and waste minimization through green production practices
  62. Topical Issue on Conference on Materials, Manufacturing Processes and Devices - Part I
  63. Characterization of Co–Ni–TiO2 coatings prepared by combined sol-enhanced and pulse current electrodeposition methods
  64. Hot deformation behaviors and microstructure characteristics of Cr–Mo–Ni–V steel with a banded structure
  65. Effects of normalizing and tempering temperature on the bainite microstructure and properties of low alloy fire-resistant steel bars
  66. Dynamic evolution of residual stress upon manufacturing Al-based diesel engine diaphragm
  67. Study on impact resistance of steel fiber reinforced concrete after exposure to fire
  68. Bonding behaviour between steel fibre and concrete matrix after experiencing elevated temperature at various loading rates
  69. Diffusion law of sulfate ions in coral aggregate seawater concrete in the marine environment
  70. Microstructure evolution and grain refinement mechanism of 316LN steel
  71. Investigation of the interface and physical properties of a Kovar alloy/Cu composite wire processed by multi-pass drawing
  72. The investigation of peritectic solidification of high nitrogen stainless steels by in-situ observation
  73. Microstructure and mechanical properties of submerged arc welded medium-thickness Q690qE high-strength steel plate joints
  74. Experimental study on the effect of the riveting process on the bending resistance of beams composed of galvanized Q235 steel
  75. Density functional theory study of Mg–Ho intermetallic phases
  76. Investigation of electrical properties and PTCR effect in double-donor doping BaTiO3 lead-free ceramics
  77. Special Issue on Thermal Management and Heat Transfer
  78. On the thermal performance of a three-dimensional cross-ternary hybrid nanofluid over a wedge using a Bayesian regularization neural network approach
  79. Time dependent model to analyze the magnetic refrigeration performance of gadolinium near the room temperature
  80. Heat transfer characteristics in a non-Newtonian (Williamson) hybrid nanofluid with Hall and convective boundary effects
  81. Computational role of homogeneous–heterogeneous chemical reactions and a mixed convective ternary hybrid nanofluid in a vertical porous microchannel
  82. Thermal conductivity evaluation of magnetized non-Newtonian nanofluid and dusty particles with thermal radiation
https://doi.org/10.1515/htmp-2024-0035
Schlagwörter für diesen Artikel
coral aggregate seawater concrete (CASC); wetting–drying cycle; law of sulfate ion diffusion; COMSOL
Creative Commons
BY 4.0

Artikel in diesem Heft

  1. Research Articles
  2. De-chlorination of poly(vinyl) chloride using Fe2O3 and the improvement of chlorine fixing ratio in FeCl2 by SiO2 addition
  3. Reductive behavior of nickel and iron metallization in magnesian siliceous nickel laterite ores under the action of sulfur-bearing natural gas
  4. Study on properties of CaF2–CaO–Al2O3–MgO–B2O3 electroslag remelting slag for rack plate steel
  5. The origin of {113}<361> grains and their impact on secondary recrystallization in producing ultra-thin grain-oriented electrical steel
  6. Channel parameter optimization of one-strand slab induction heating tundish with double channels
  7. Effect of rare-earth Ce on the texture of non-oriented silicon steels
  8. Performance optimization of PERC solar cells based on laser ablation forming local contact on the rear
  9. Effect of ladle-lining materials on inclusion evolution in Al-killed steel during LF refining
  10. Analysis of metallurgical defects in enamel steel castings
  11. Effect of cooling rate and Nb synergistic strengthening on microstructure and mechanical properties of high-strength rebar
  12. Effect of grain size on fatigue strength of 304 stainless steel
  13. Analysis and control of surface cracks in a B-bearing continuous casting blooms
  14. Application of laser surface detection technology in blast furnace gas flow control and optimization
  15. Preparation of MoO3 powder by hydrothermal method
  16. The comparative study of Ti-bearing oxides introduced by different methods
  17. Application of MgO/ZrO2 coating on 309 stainless steel to increase resistance to corrosion at high temperatures and oxidation by an electrochemical method
  18. Effect of applying a full oxygen blast furnace on carbon emissions based on a carbon metabolism calculation model
  19. Characterization of low-damage cutting of alfalfa stalks by self-sharpening cutters made of gradient materials
  20. Thermo-mechanical effects and microstructural evolution-coupled numerical simulation on the hot forming processes of superalloy turbine disk
  21. Endpoint prediction of BOF steelmaking based on state-of-the-art machine learning and deep learning algorithms
  22. Effect of calcium treatment on inclusions in 38CrMoAl high aluminum steel
  23. Effect of isothermal transformation temperature on the microstructure, precipitation behavior, and mechanical properties of anti-seismic rebar
  24. Evolution of residual stress and microstructure of 2205 duplex stainless steel welded joints during different post-weld heat treatment
  25. Effect of heating process on the corrosion resistance of zinc iron alloy coatings
  26. BOF steelmaking endpoint carbon content and temperature soft sensor model based on supervised weighted local structure preserving projection
  27. Innovative approaches to enhancing crack repair: Performance optimization of biopolymer-infused CXT
  28. Structural and electrochromic property control of WO3 films through fine-tuning of film-forming parameters
  29. Influence of non-linear thermal radiation on the dynamics of homogeneous and heterogeneous chemical reactions between the cone and the disk
  30. Thermodynamic modeling of stacking fault energy in Fe–Mn–C austenitic steels
  31. Research on the influence of cemented carbide micro-textured structure on tribological properties
  32. Performance evaluation of fly ash-lime-gypsum-quarry dust (FALGQ) bricks for sustainable construction
  33. First-principles study on the interfacial interactions between h-BN and Si3N4
  34. Analysis of carbon emission reduction capacity of hydrogen-rich oxygen blast furnace based on renewable energy hydrogen production
  35. Just-in-time updated DBN BOF steel-making soft sensor model based on dense connectivity of key features
  36. Effect of tempering temperature on the microstructure and mechanical properties of Q125 shale gas casing steel
  37. Review Articles
  38. A review of emerging trends in Laves phase research: Bibliometric analysis and visualization
  39. Effect of bottom stirring on bath mixing and transfer behavior during scrap melting in BOF steelmaking: A review
  40. High-temperature antioxidant silicate coating of low-density Nb–Ti–Al alloy: A review
  41. Communications
  42. Experimental investigation on the deterioration of the physical and mechanical properties of autoclaved aerated concrete at elevated temperatures
  43. Damage evaluation of the austenitic heat-resistance steel subjected to creep by using Kikuchi pattern parameters
  44. Topical Issue on Focus of Hot Deformation of Metaland High Entropy Alloys - Part II
  45. Synthesis of aluminium (Al) and alumina (Al2O3)-based graded material by gravity casting
  46. Experimental investigation into machining performance of magnesium alloy AZ91D under dry, minimum quantity lubrication, and nano minimum quantity lubrication environments
  47. Numerical simulation of temperature distribution and residual stress in TIG welding of stainless-steel single-pass flange butt joint using finite element analysis
  48. Special Issue on A Deep Dive into Machining and Welding Advancements - Part I
  49. Electro-thermal performance evaluation of a prismatic battery pack for an electric vehicle
  50. Experimental analysis and optimization of machining parameters for Nitinol alloy: A Taguchi and multi-attribute decision-making approach
  51. Experimental and numerical analysis of temperature distributions in SA 387 pressure vessel steel during submerged arc welding
  52. Optimization of process parameters in plasma arc cutting of commercial-grade aluminium plate
  53. Multi-response optimization of friction stir welding using fuzzy-grey system
  54. Mechanical and micro-structural studies of pulsed and constant current TIG weldments of super duplex stainless steels and Austenitic stainless steels
  55. Stretch-forming characteristics of austenitic material stainless steel 304 at hot working temperatures
  56. Work hardening and X-ray diffraction studies on ASS 304 at high temperatures
  57. Study of phase equilibrium of refractory high-entropy alloys using the atomic size difference concept for turbine blade applications
  58. A novel intelligent tool wear monitoring system in ball end milling of Ti6Al4V alloy using artificial neural network
  59. A hybrid approach for the machinability analysis of Incoloy 825 using the entropy-MOORA method
  60. Special Issue on Recent Developments in 3D Printed Carbon Materials - Part II
  61. Innovations for sustainable chemical manufacturing and waste minimization through green production practices
  62. Topical Issue on Conference on Materials, Manufacturing Processes and Devices - Part I
  63. Characterization of Co–Ni–TiO2 coatings prepared by combined sol-enhanced and pulse current electrodeposition methods
  64. Hot deformation behaviors and microstructure characteristics of Cr–Mo–Ni–V steel with a banded structure
  65. Effects of normalizing and tempering temperature on the bainite microstructure and properties of low alloy fire-resistant steel bars
  66. Dynamic evolution of residual stress upon manufacturing Al-based diesel engine diaphragm
  67. Study on impact resistance of steel fiber reinforced concrete after exposure to fire
  68. Bonding behaviour between steel fibre and concrete matrix after experiencing elevated temperature at various loading rates
  69. Diffusion law of sulfate ions in coral aggregate seawater concrete in the marine environment
  70. Microstructure evolution and grain refinement mechanism of 316LN steel
  71. Investigation of the interface and physical properties of a Kovar alloy/Cu composite wire processed by multi-pass drawing
  72. The investigation of peritectic solidification of high nitrogen stainless steels by in-situ observation
  73. Microstructure and mechanical properties of submerged arc welded medium-thickness Q690qE high-strength steel plate joints
  74. Experimental study on the effect of the riveting process on the bending resistance of beams composed of galvanized Q235 steel
  75. Density functional theory study of Mg–Ho intermetallic phases
  76. Investigation of electrical properties and PTCR effect in double-donor doping BaTiO3 lead-free ceramics
  77. Special Issue on Thermal Management and Heat Transfer
  78. On the thermal performance of a three-dimensional cross-ternary hybrid nanofluid over a wedge using a Bayesian regularization neural network approach
  79. Time dependent model to analyze the magnetic refrigeration performance of gadolinium near the room temperature
  80. Heat transfer characteristics in a non-Newtonian (Williamson) hybrid nanofluid with Hall and convective boundary effects
  81. Computational role of homogeneous–heterogeneous chemical reactions and a mixed convective ternary hybrid nanofluid in a vertical porous microchannel
  82. Thermal conductivity evaluation of magnetized non-Newtonian nanofluid and dusty particles with thermal radiation
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