Influence of microalloying with B on the microstructure and properties of brazed joints with Ag–Cu–Zn–Sn filler metal

Sujuan Zhong; Yinkai Shi; Yunpeng Li; Jian Qin; Hua Yu; Datian Cui; Weimin Long

doi:10.1515/ntrev-2022-0509

Article Open Access

Influence of microalloying with B on the microstructure and properties of brazed joints with Ag–Cu–Zn–Sn filler metal

Sujuan Zhong , Yinkai Shi , Yunpeng Li , Jian Qin , Hua Yu , Datian Cui and Weimin Long

Published/Copyright: February 28, 2023

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From the journal Nanotechnology Reviews Volume 12 Issue 1

Abstract

Processing and formation of Ag–Cu–Zn–Sn filler metals with high Sn content are difficult owing to their high brittleness. A composite flux-cored silver (Ag) filler metal of a CuSn + XB alloy powder was designed using the principle of in situ synthesis. Copper–Copper (Cu–Cu) joints were obtained using a novel Ag-based filler metal (at B contents of 0, 2, and 3%). The microstructure and evolution of the mechanical properties of the Cu–Cu brazed joints were studied by field emission scanning electron microscopy, electron probe microscope, electron backscattering diffraction, tensile testing, and nanoindentation tester. The brazed joints mainly consisted of Ag-based solid solution (Ag(s.s)) and Cu-based solid solution (Cu(s.s)). Due to the addition of 3% B, (Ag + Cu) eutectic network structures were formed in the brazing seam. At the same time, the grain size, texture strength, misorientation distribution, and deformation of Ag(s.s) and Cu(s.s) in the brazing seam changed significantly. The overall microhardness of the brazing seam significantly increased as the B content increased in the filler metals. The tensile strength of the joints followed a parabola. At the B content of 2%, the ultimate tensile strength of the Cu–Cu joints was 248.0 MPa. The brazed joints featured intergranular, dimple, and cleavage fractures.

Keywords: in situ synthesis; microstructure; solid solution strengthening; grain refinement; texture

1 Introduction

In recent years, Ag-based filler metals with many advantages (such as high strength, high thermal and electrical conductivity, high oxidation and corrosion resistance, and suitable melting point) have been widely used for brazing Cu, low-carbon steel, stainless steel, nickel-based alloys, and other materials [1,2,3,4,5,6]. Ag–Cu–Zn filler metals are widely used as Ag-based filler metals. The addition of Cu and Zn increases the commercial applicability of silver (Ag) filler metals by lowering the liquidus and solidus temperatures of the filler metal and reducing the amount of Ag added. However, Cu and Zn forms CuZn compounds and Ag–Cu–Zn eutectic phases (mainly including β-CuZn and γ-Cu₅Zn₈ phases) [7,8]. CuZn compounds are hard and brittle, which affect the performance of the brazed joints. The addition of Cd further reduces the solidus and liquidus temperatures of the filler metal, meanwhile brittle phase and eutectic structure were not formed in brazed seam [9,10]. Therefore, Cd has been widely used in Ag-based filler metals for brazing Cu, stainless steel, and other alloys. Since Cd is harmful to human health, the electrical equipment industry in most countries must comply with instructions to limit the use of Cd in electrical and electronic equipment [11,12]. Thus, the exploration of Cd substitutes has become important for meeting the requirements for the use of filler metals.

Schnee et al. [13] prepared an Ag–Cu–Zn–Sn filler metal by replacing Cd with Sn. It was found that Sn reduced the solid-liquidus temperature of the Ag-based filler metal and improved the wettability of the filler metal on the surface of the base metal. However, the Ag–Cu–Zn–Sn filler metal without Cd exhibited a higher melting point, higher melting range, and lower wettability and weldability than that with Cd. These limited the application of Ag-based filler metals in the aerospace, home appliance, and electronics industries. In-depth and systematic studies have been conducted for improving the performance of Cd-free Ag–Cu–Zn–Sn filler metals [14,15,16]. Researchers have found that the addition of a suitable element at an appropriate content can improve the performance of brazed joints. Improvement in the performance of Ag-based filler metal upon the addition of rare earth elements has been reported [12,17]. Although significant attention has been devoted to Ag-based filler metals, their Ag content is very high.

To alleviate the disadvantages of the elemental Sn addition to Ag–Cu–Zn–Sn filler metals (e.g., high brittleness, processing difficulty, and poor wettability), novel composite flux-core Ag-based filler metals were prepared by using flux-core filler metals via in situ synthesis methods [18,19]. In this approach, during the brazing process, the flux in the core, which is heated and melted, covers the surface of the brazing seam. The flux removes the oxide film from the filler metals and surface of the brazing material. As the temperature continues to increase, fusion and diffusion occur between the plastic Ag–Cu–Zn–Sn filler metal in the outer layer and the CuSn/B alloy powder in the core. The Ag–Cu–Zn–Sn filler metal with a high Sn content was prepared using the in situ synthesis method.

In this study, novel composite flux-core Ag-based filler metals with different contents of B were prepared by using flux-core filler metals via in situ synthesis methods. The effect of the addition of B (B = 0, 2, and 3 wt%) powders with different contents on the microstructure and properties of Cu–Cu brazed joints was investigated by using Ag-based brazing materials. The effects of B addition on the grain size, texture strength, deformation, and hardness of Ag(s.s) and Cu(s.s) were systematically studied.

2 Materials and methods

T2 copper was employed in the present study (dimensions, 60 × 20 × 3 mm³). A novel flux-cored Ag–Cu–Zn–Sn (BAg30T) filler metal was used in the tests. A Cu₆₀Sn₄₀ metal powder (particle size, 50 μm) and B intermediate alloy powder were used. The flux was a custom-made composite borate flux. The flux, the Cu₆₀Sn₄₀ alloy powder, and the B powder were mixed and weighed according to the standard mass ratio, and then placed in a ball mill for thorough mixing. After uniform mixing, a composite Ag-based flux-cored filler metal sample (diameter, 3 mm) was formed by rolling, drawing, and other processes. The structure of the composite filler metal is shown schematically in Figure 1, while its specific composition is listed in Table 1.

Figure 1

Schematic of the structure of the composite flux-cored Ag base filler metal.

Table 1

Chemical composition of the BAg30T filler metal (wt%)

Alloy	Core proportion			Chemical composition
Alloy	Alloy powder	B	Flux	Ag	Cu	Zn	Sn
0	30	0	70	30	37	32	1
1	30	2	68	30	37	32	1
2	30	3	67	30	37	32	1

The quality of the brazed joints depends on factors such as filler metal, brazing flux, and brazing process. The filler metal and brazing flux were determined in this experiment; therefore, the welding quality depended on the control of the brazing process. High-frequency induction brazing can yield local heating owing to the resistance heat of the induction current. Therefore, it is characterized by easy heat concentration, fast heating, relatively low surface oxidation, relatively high production efficiency, and low environmental pollution. In addition, it prevents the grain growth and recrystallization of the filler metal. Consequently, it is widely used for brazing cemented carbides, nonferrous metals, and ferrous metals. In this experiment, a Cu/Cu butt test was performed adopting an induction brazing process. Before testing, a Cu plate was washed in a metal-cleaning agent for cleaning the oil stains on the surface of the sample. The surface of the welded specimen was polished using sandpaper, and the surface of the specimen was cleaned using alcohol. The lap joint using a special fixture is shown schematically in Figure 2. The power and the water-cooling system were first turned on, following which the preheating of the induction coil was performed after the normal circulation of the cooling water. Then, the welding current was adjusted to 40 A, and the welding was started. After the flux and filler metal were completely melted, they were kept warm for 10 s, and the heating switch was then turned off and cooled to room temperature.

Figure 2

Schematic of the lap joint of a brazed joint (mm).

Microstructural specimens (dimensions, 20 × 3 × 1 mm³) were prepared by wire cutting, and standard metallographic specimens were prepared using a metallographic inlay machine. Metallographic specimens were ground using 400#, 600#, 800#, 1,200#, 1,500#, and 2,000# sandpapers and polished using a water-soluble polishing paste. The prepared metallographic samples were observed through scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). The phase composition, grain size, weave strength, orientation difference distribution, and degree of deformation of the joints were analyzed through SEM-EDS, electron probe microanalysis (EPMA), and electron backscatter diffraction (EBSD) analysis.

The microhardness of the joints was characterized using a nanoindentation tester (G200) in the constant indentation depth mode. The indentation depth was 400 nm and the spacing between the two points was 13 μm. To obtain more accurate nanoindentation data, five areas were selected for measurements. The average values were derived using the Origin software. The tensile strength of the joints at room temperature was measured using a universal tensile testing machine at a tensile rate of 5 mm/min. The average value for each group was obtained from the tensile strengths of the three tensile specimens. The fracture morphology after failure was analyzed through SEM.

3 Results and discussion

3.1 Effect of B on the microstructure of the brazed joints

The SEM images of the brazed joints after adding different amounts of B are shown in Figure 3. A good weld morphology was observed for all three alloy powder cores, and no cracks were observed. Obvious transition areas were observed at the junction between Cu and the brazing seam. The transition zone was caused by the lower Cu content of the brazing seam than that of the base material, resulting in a concentration gradient during the welding process. The brazing seam consisted of a white block, black matrix, and lattice-like eutectic structure. When elemental B was not added, the brazed joints were composed of a white bulk phase, gray-black matrix phase, and small fraction of lattice-like eutectic structures. The white bulk phase was aggregated in the central region and allowed regional segregation in the brazing seam. Upon the addition of elemental B, the white phase in the brazing seam diffused from the central region to the base material and became more uniformly distributed. Simultaneously, the fraction of lattice-like eutectic structures in the brazing seam gradually increased. When the B content was 3%, the white massive tissue in the brazing seam transformed to a lattice-like eutectic tissue. EDS was conducted for determining the composition of the phases; the composition of each phase is listed in Table 2. Evidently, the gray matrix phase in the brazing seam was Cu(s.s), the white phase was Ag(s.s), and the mesh structure was the (Ag + Cu) eutectic structure. Figure 3(g)–(i) shows the line scan results of the joints [10,17,20,21]. Evidently, the Cu content gradually decreased from the base material to the brazing seam, consistent with the results of the above-described analysis of the transition layer. In the brazing area, the region where the Cu content was higher than the Ag content was Cu(s.s). Conversely, the region in which the Ag content was higher than the Cu content was Ag(s.s). In the lattice structure, the area where Ag(s.s) and Cu(s.s) were combined was associated with a typical (Ag + Cu) eutectic structure [22,23]. The line scan data also showed that the elemental B content was higher in Ag(s.s) than in other regions. Presumably, B was mainly dissolved in Ag to form Ag(s.s) through the solute form.

Figure 3

SEM images of (a) 0%, (b) 2%, and (c) 3% brazed joints. (d, e, and f) 0, 2, and 3% brazed joint line scanning positions and (g, h, and i) 0, 2, and 3% line scan results.

Table 2

Mass phase energy spectral data of the brazed joints of the Ag-based composite core filler metal in Figure 3

Points	Cu	Ag	Zn	Sn
1	99.34	0.00	0.63	0.02
2	77.18	3.83	18.74	0.24
3	19.48	58.80	18.94	2.63
4	22.16	47.46	18.77	7.28
5	99.20	0.26	0.46	0.08
6	26.21	42.58	24.59	6.61

It is inaccurate to analyze the distribution of B on the basis of only line scan results. To further investigate the distribution of elemental B in the brazed joints, face scanning via EPMA was performed on the brazed joints; the elemental distributions are shown in Figures 4 and 5. Different colors represent different degrees of the elemental B distribution. The correspondence between the colors and degree of elemental aggregation is shown in the heat distribution diagram on the right. It can be seen that Cu is mainly distributed in the base material as well as on both sides of Ag(s.s), and the Cu content of the brazing seam is lower than that of the Cu base material. Similarly, Ag is mainly distributed in the center of the brazing seam and in the form of a small amount of solute in Cu(s.s). This finding is consistent with the results of a previous study. In addition, the distribution of Zn is consistent with that of Cu, and it is slightly distributed in Ag(s.s). The distribution of Sn and B is consistent with that of Ag, and trace amounts of Sn and B are distributed in Cu(s.s). Therefore, it can be concluded that B is mainly dissolved in Ag to form Ag(s.s) in the form of a solute. Solid solution strengthening was performed to reinforce the joints’ properties.

Figure 4

Surface scan distribution of the joint with 2% B. (a) Cross-sectional morphologies of the joint, (b) Ag, (c) Cu, (d) Zn, (e) Sn, and (f) B.

Figure 5

Surface scan distribution of the joint with 3% B. (a) Cross-sectional morphologies of the joint, (b) Ag, (c) Cu, (d) Zn, (e) Sn, and (f) B.

In the brazing process, the temperature rises rapidly beyond the melting point of the filler metal but is lower than the melting point of the base metal. Because cooling is air-mediated, it is easy to produce a eutectic structure during rapid heating and cooling. The factors affecting the element solid solubility mainly include the sub-radius, electronegativity, and electron concentration. The atomic radii, electronegativities, and crystal structures of the elements in the filler metals are listed in Table 2. Clearly, the atomic radii of Zn, Sn, Cu, Ag, and B differ insignificantly; thus, only substitutional solid solutions could be formed [24]. The difference between the atomic radii of Zn and Cu is smaller than that of Zn and Ag, and the difference between the atomic radii of Sn and Ag is smaller than that of Sn and Cu. The ternary phase diagram of Ag–Cu–Zn shows that the melting point of Cu(s.s) is higher than that of Ag(s.s); Cu and Ag have face-centered cubic (FCC) structures, while Zn has a close-packed hexagonal (HCP) structure; this is owing to the low solubility of B in copper. During the cooling process of the joints, trace amounts of Ag, Sn, and B and large amounts of Zn dissolve in copper, yielding Cu(s.s) [25]. With the decrease in the temperature, the contents of Ag, Cu, Zn, Sn, and B decrease, and the remaining Cu, Zn, Sn, and B dissolve in Ag, forming Ag(s.s). Upon the addition of B, B dissolves in Ag to allow solid solution strengthening and further diffusion of Ag(s.s) in the brazing seam. Thus, a more evident grid-like eutectic structure is obtained and dispersion strengthening is realized. Solid solution strengthening and dispersion strengthening improve the performance of joints, whereas the presence of the eutectic structure decreases the performance of joints (Table 3).

Table 3

Atomic radius (pm), electronegativity, and atomic structure of the elements in the filler metal

	Cu	Ag	Zn	Sn	B
Atomic radius	127	144	125	140	117
Electronegativity	1.9	1.9	1.6	1.8	2.0
Atomic structure	FCC	FCC	HCP	BCC	—

3.2 EBSD analysis

3.2.1 Effect of B on the grain size and texture of the Ag and Cu solid solutions

Figure 6 shows the grain distributions for Ag(s.s) and Cu(s.s) in the brazed joints upon the addition of different amounts of B. The average grain sizes after the calculation are listed in Table 4. Upon the addition of B, the grain sizes of Ag(s.s) and Cu(s.s) decrease, indicating that the addition of elemental B can refine the grains of these two phases. When the content of element B is 2%, the grain size of silver solid solution and copper solid solution is the smallest. Figure 7 shows the inverse pole figures (IPF) of the brazing seam. The correspondence between the colors and crystals is shown in the spherical triangle in the upper-right corner. The grain orientations for Ag(s.s) and Cu(s.s) are anisotropic. Grain anisotropy causes the joints to exhibit good mechanical properties. The pole figures of Ag(s.s) and Cu(s.s) in the brazed joints at different B contents are shown in Figure 8. Clearly, upon the elemental B addition, the grains of Cu(s.s) and Ag(s.s) exhibit texture characteristics, and the texture strength for both the phases decreases. This is consistent with the results observed after the change in the grain sizes of Cu(s.s) and Ag(s.s), as summarized in Table 4. It can be seen that grain refinement decreases the texture strength, which is consistent with the results reported by Zhang et al. [26,27].

Figure 6

Distribution of the grain sizes of Ag(s.s) and Cu(s.s) in the brazing seam. (a₁) and (a₂) 0%; (b₁) and (b₂) 2%; (c₁) and (c₂) 3%.

Table 4

Average grain size statistics for Ag(s.s) and Cu(s.s) in the brazing seam (μm)

B (wt%)	Ag	Cu
0	4.03	4.56
2	2.90	2.47
3	3.19	2.89

Figure 7

IPF diagrams for Ag(s.s) and Cu(s.s) in the brazing seam. (a) 0%; (b) 2%; and (c) 3%.

Figure 8

Pole figures of Ag(s.s) and Cu(s.s) in the brazing seam. (a₁) and (a₂) 0%; (b₁) and (b₂) 2%; (c₁) and (c₂) 3%.

3.2.2 Misorientation angle and strain distribution within the brazing seam

According to the coincidence site lattice (CSL) mode, grain boundaries can be divided into three types: (1) CSL, (2) low-angle grain boundaries (LAGBs), and (3) random high-angle grain boundaries (HAGBs) [28]. Misorientation angles below 2° were not considered to eliminate spurious boundaries caused by the orientation noise. LAGBs are characterized by the grain boundary misorientation angles in the 2–15° range, while HAGBs are characterized by the grain boundary misorientation angles at >15° [29]. Figure 9 shows the misorientation angles of Ag(s.s) and Cu(s.s) in the brazing seam, while Table 5 summarizes the statistics of the corresponding HAGBs and LAGBs. The misorientation angle distributions of Ag(s.s) and Cu(s.s) are relatively scattered when elemental B is not present. Upon the addition of elemental B, the misorientation angle distributions of the two phases become more concentrated. The frequencies of the misorientation angle distributions of Ag(s.s) and Cu(s.s) in the two cases show a parabolic trend. The HAGBs of Ag(s.s) without elemental B account for 88.9%, while the LAGBs of Cu(s.s) account for 83.9%. Upon the elemental B addition at 3%, the proportions of Ag(s.s) and Cu(s.s) in the brazed joints are 94.0 and 93.7%, respectively. The percentage of HAGBs increases with the addition of elemental B. Upon the addition of elemental B, the grains of Ag(s.s) and Cu(s.s) become more refined. Plastic deformation between adjacent grains increases the lattice distortion at the grain boundaries. Such plastic deformation can yield fewer LAGBs. Therefore, the misorientation angle of LAGBs increases, whereas the proportion of HAGBs increases. Existing research results suggest that HAGBs exhibit a stronger tendency to crack, which negatively affects the joints’ mechanical properties, whereas LAGBs can hinder the formation and propagation of defects [28].

Figure 9

Distribution of the misorientation angle between Ag(s.s) and Cu(s.s) within the brazing seam. (a) 0%; (b) 2%; and (c) 3%.

Table 5

Statistics of the misorientation angle of Ag(s.s) and Cu(s.s) in the brazing seam

	Ag (%)		Cu (%)
	2–15°	15°≧	2–15°	15°≧
0% B	3.6	88.9	2.7	84.0
2% B	2.1	6.5	1.8	6.3
3% B	4.7	94.0	4.8	93.7

The plastic deformation between adjacent grains of different sizes can lead to the transformation of LAGBs to HAGBs. Grain refinement leads to the redistribution of stress and strain, and defects (such as holes and cracks) are more likely to be formed in the areas of stress concentration and weak bonding. The kernel average misorientation (KAM) value captures the strain concentration in grains and grain boundaries, as well as the distribution and evolution of plastic deformation. The distribution of the KAM values for the brazing seam is shown in Figure 10. Different colors represent different degrees of strain concentration, which reflect the plastic deformation ability of the grain interior and grain boundary [30]. With the increase in the B content, the degree of deformation within the grains and grain boundaries increases. When the degree of deformation is small, the plastic deformation within the grain occurs earlier than that at the grain boundary, indicating that the strength of the grain is lower than that of the grain boundary. At the B mass ratio of 3%, a large local stress concentration appears at the grain boundary, affecting the joints’ mechanical properties.

Figure 10

Deformation of Ag(s.s) and Cu(s.s) within the brazing seam. (a) 0%; (b) 2%; and (c) 3%.

3.3 Effect of B on the mechanical properties of the joints

3.3.1 Microhardness

Figure 11 shows the distribution of indentations in the brazing seam. Figure 12 shows the experimental results of nanoindentation in the brazing seam. To ensure the accuracy of the data, for each sample, the reported results are taken as an average over the five replicate measurements. Evidently, the hardness distribution comprises three parts: (1) base metal regime, (2) transition layer regime, and (3) brazing seam regime. The microhardness of the brazing seam gradually increases with the increase in the B content. The hardness is maximal upon the addition of 3% B. The microhardness of the brazing seam is higher than that of the base material.

Figure 11

Distribution of hardness of the brazing seam: (a) 0%; (b) 2%; and (c) 3%.

Figure 12

Average hardness of the brazing seam.

According to the results of the above-described analysis, the addition of elemental B enhances the grain refinement of Ag(s.s) and Cu(s.s). These fine grains hinder the indentation upon pressing into the sample, thus increasing the sample hardness [20,24,31]. Upon the addition of 3% B, a large amount of the eutectic tissue is produced in the brazing seam. Stress concentration is easily generated when an indenter is pressed into a sample, further increasing the hardness of the sample.

3.3.2 Effect of B on the shear tensile properties of the joints

The effect of B content on the mechanical properties of the brazed joints was further investigated. Tensile tests were performed on the brazed joints, and the results are shown in Figure 13. Upon the addition of elemental B, the strength of the brazed joints could be described by a parabola. The maximal strength of the brazed joints was 248 MPa at a B content of 2%. At higher B contents, the strength of the joints decreased. This trend could be explained by referring to the microstructure of the brazed joints. Solid solution strengthening was observed in the presence of Ag(s.s) and Cu(s.s). With the addition of elemental B, Ag(s.s) in the brazed joints exhibited obvious diffusion and uniform distribution, thereby increasing dispersion. The grain refinement of Ag(s.s) and Cu(s.s) in the brazing seam was also observed. Solid solution strengthening, dispersion strengthening, and grain refinement acted to increase the strength of the joints. At 3% B, a significant eutectic structure was discovered in the brazing seam. The HAGBs and the deformation degree of Ag(s.s) and Cu(s.s) in the brazing seam increased, increasing the cracking tendency and localized stress concentration in the joints. The eutectic structure, lattice distortion, and stress concentration in the brazed joints weakened the strength of the joints.

Figure 13

Tensile strength of brazed joints.

The effect of the tensile fracture morphology of the brazed joints after stretching the sample is shown in Figure 14. In the absence of elemental B, almost completely fine grains appeared on the fracture, corresponding to a clear intergranular fracture. Intergranular fractures are brittle fractures. At 2% B, dimples appeared in the fracture, corresponding to a ductile fracture. At 3% B, small uneven steps appeared on the fracture surface, corresponding to a cleavage fracture. Therefore, upon the addition of B, the fracture morphology of the joints changed from that of the intergranular fracture to dimple fracture and finally to cleavage fracture.

Figure 14

Fracture morphology of the joints at (a) 0%; (b) 2%; and (c) 3%.

4 Conclusion

In this study, the effects of elemental B in filler metals on the microstructure and mechanical properties of Cu–Cu brazed joints were investigated. The following conclusions were drawn based on the experimental results:

The microstructure of the joints mainly consisted of Ag(s.s) and Cu(s.s). A grid-like Ag–Cu eutectic structure was discovered as the B content increased.
As the addition of elemental B increased, the grains of Ag(s.s) and Cu(s.s) in the joints were refined, and the texture strength was weakened. The HAGBs ratio and plastic deformation were more pronounced.
The microhardness of the brazing seam gradually increased with the increase in the B content, and the microhardness of the brazing seam was higher than that of the base metal.
Since the addition of elemental B, the strength of the brazed joints could be described by a parabola. The maximal strength of the brazed joints was 248 MPa when the B content was 2%. The fracture forms of the brazed joints were intergranular, dimple, and cleavage fractures.

Acknowledgments

The authors wish to thank for supporting this work by the Basic manufacturing hot working process database in the National Key R&D Program of China (No. 2020YFB2008400); Project (20A430013) supported by the Education Department of Henan Province, China; Key project of Henan Province in 2021 (202102210443); National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials, 2021, Open Project (HKDNM202104); National Natural Science Foundation of China (U1904197).

Funding information: This work is supported by the Basic manufacturing hot working process database in the National Key R&D Program of China (No. 2020YFB2008400); Project (20A430013) supported by the Education Department of Henan Province, China; Key project of Henan Province in 2021 (202102210443); National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials, 2021, Open Project (HKDNM202104); National Natural Science Foundation of China (U1904197).
Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
Conflict of interest: The authors state no conflict of interest.

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Received: 2022-08-03

Revised: 2022-10-12

Accepted: 2023-01-03

Published Online: 2023-02-28

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

Articles in the same Issue

https://doi.org/10.1515/ntrev-2022-0509

Keywords for this article

in situ synthesis; microstructure; solid solution strengthening; grain refinement; texture

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