Volume 23, Issue 2

In this work, based on the quasi-static tensile test and acoustic emission technology, the tensile properties of two types of three-dimensional flat-knitted inlay fabrics reinforced composites are investigated, and the acoustic emission characteristic parameters of various damage mechanisms are obtained. The transverse tensile process of specimens could be divided into the elastic stage, yield stage, and fracture stage. We found that, compared with the fluctuation of the stress-strain curve in the yield stage, weft insertion yarns in composite with interlock structure broke almost simultaneously, while the composite with plain stitch broke successively. The transverse and longitudinal tensile strength of the composite with interlock structure was 44.70% and 28.63% higher than the composite with plain structure, respectively. The SEM micrographs showed that the damage mechanism of the composites was matrix fracture, fiber-matrix debonding, and fiber breakage. The amplitude ranges of the three damage mechanisms were 50–65 dB, 65–80 dB, and 90–100 dB, respectively, and the frequency ranges were 35–114 kHz, 116–187 kHz, and 252–281 kHz, respectively. Fiber-matrix debonding and matrix fracture had large cumulative AE energy, numerous events, and long duration time, while fiber breakage had the characteristics of large amplitude, high frequency, low cumulative AE energy, few events, and short duration time.

Graduated compression is widely used for medical application to prevent perioperative venous thromboembolism, but other applications such as sportswear can potentially also benefit from it. A tight-fit cycling shirt meant to ensure the correct position during cycling and prevent injuries was designed. The aim of this study was to improve garment pattern design from the aspect of clothing pressure for providing support and enhancing comfort to the user. This paper investigates the suitability of pressure maps from 3D fashion design software CLO 3D for design and in particular its capability to discriminate between various materials and cycling postures. Moreover, the impact of the mechanical properties of fabric was analyzed. In particular, virtual prototyping tool CLO 3D and pressure mapping were employed to achieve the required graduated compression while ensuring fit and comfort. Pattern adjustments were iteratively performed until stress, strain, and pressure maps showed adequate fit and pressure of the cycling garment on the virtual cyclist in static and dynamic cycling positions. The impact of fabric types on garment fit has been shown by generating the stress, strain, and pressure maps with a virtual simulation. It was found that the visualized pressure on the human body model shows distributions that are related to contact between body and garment, and large compression stresses occur in the lower parts of the two shirts. Evident garment deformation was shown at hip level, upper arm, lower front side seam, and front neck, which can reduce garment wear comfort and freedom of movement. The output was found to be sufficiently accurate to optimize the garments based on material and cycling posture.

Natural silk fiber derived from the Bombyx mori (B. mori) silkworm has long been used as a luxury raw material in textile industry because of its shimmering appearance and durability, and as surgical suture for its high strength and flexibility. Regenerated silk fibroin, as the main protein extracted from the cocoons of the B. mori silkworm, recently has gained considerable attention due to its outstanding properties, including facile processability, superior biocompatibility, controllable biodegradation, and versatile functionalization. Tremendous effort has been made to fabricate silk fibroin into various promising materials with controlled structural and functional characteristics for advanced utilities in a multitude of biomedical applications, flexible optics, electronics devices, and filtration systems. Herein, reverse engineered silk fibroin extraction methods are reviewed, recent advances in extraction techniques are discussed. Fabrication methods of silk fibroin materials in various formats are also addressed in detail; in particular, progress in new fabrication technologies is presented. Attractive applications of silk fibroin-based materials are then summarized and highlighted. The challenges faced by current approaches in production of silk fibroin-based materials and future directions acquired for pushing these favorable materials further toward above mentioned applications are further elaborated.

Interface phenomena that occur at the solid–liquid interface, such as wettability, adsorption, and particle aggregation, depend on the kind and magnitude of the solid surface free energy and electrokinetic properties found in water solutions. These phenomena are crucial for textile dyeing, finishing, and care. They characterize the material surface and change with different material pretreatment and finishing. In this paper, electrokinetic potential, isoelectric point, point of zero charge, a specific amount of surface charge and surface free energy of raw, enzymatically scoured, bleached, and finished cotton fabrics were investigated. Electrokinetic potential was measured by a streaming potential method and a specific quantity of surface charge by the back-titration method. For determination of the solid surface free energy components, the thin-layer wicking and contact-angle methods were used. On the basis of these results, components of solid surface free energy were calculated and discussed.

Through biogenetic engineering, the posterior silk glands of Bombyx mori larvae are degenerated, and only the middle silk glands are retained to secrete sericin to produce sericin fibers, so as to obtain sericin cocoons with high sericin content (>98.5%). For this paper, sericin cocoons were studied, and the morphological structure characteristics and properties of sericin cocoons and common Bombyx mori cocoons were compared and analyzed through such modern test techniques as SEM, FTIR, and XRD. Results show that sericin cocoons have the basic morphological structure of cocoons, but because of the brittleness and hardness of sericin, the ssericin cocoons have poor integrity with a thermal decomposition rate that is higher than that of cocoons; the two cocoons are of a similar protein structure, with both α-helix and β-sheet structures, and dominantly the β-sheet structure; and the crystallinity of sericin cocoons (10.48%) is lower than that of the common Bombyx mori cocoons (27.10%). Sericin was extracted from both cocoons to obtain a mixed sericin solution respectively, which were coated on base fabrics of polyester taffeta (210T) for coating finish and subjected to qualitative research for their anti-UV properties. The base fabrics coated with mixed sericin solutions of sericin cocoons and Bombyx mori cocoons have an anti-UV performance index (UPF) of 23.9% and 22.5% respectively, which are higher than that of the base fabric (8.9%)..

This article presents a method for modeling the material characteristics of synthetic fabrics based on static tensile test results with consideration of material orthotropy. Material characteristics were determined for fabrics under load at three different angles in relation to their orthotropy. The fabrics examined were the following: polyester fabrics Bratex and Ortalion, cotton fabric with nylon and elastin fabric (poplin), and Gore-Tex membrane fabric. Considering the material mechanical characteristics, the differences were in grammage, maximum strain, and tensile strength. The study allowed us to determine the nonlinear elastic dependency between strain and stress. Test results were implemented within the Abaqus/Explicit framework for the purpose of performance of verification simulations. The correlation between simulated and experimental results was established. A high degree of similarity allows us to classify the obtained material model as usable in simulation work.

The youth of today are much more technologically adept than previous generations. This has led to many technological innovations, and the development of these innovations has in turn altered our perception of the world. The film, gaming, and clothing industries have been forced to embrace new technology to satisfy the demand of people for a more realistic virtual experience. These industries all rely on the use of 3D avatars to create virtual depictions of the human body. In the gaming and film industry, the accuracy of the avatar is not so critical. The avatars used in computer games and CGI sections of films have soft contours, which look visually appealing, but are not necessarily accurate to the human form. By contrast, the apparel industry needs to focus on creating very accurate avatars, which represent each person's body shape for virtual fitting to achieve realistic, well-fitted garments. This article describes the methods used to build an avatar and compares the draping between the following scenarios: the real avatar with a real garment, the real avatar with a virtual garment, and finally the virtual avatar with a virtual garment. This research will help to understand how the body shape can affect the virtual fit.

A study of polyvinylchloride-coated woven polyester fabric welding potential was conducted using continuous ultrasonic welding machines. The effect of cooling air, anvil wheel status, anvil wheel width, material surface contact, and welding gap on seam strength was studied. Three main welding parameters with different levels were selected based on 5 and 10 mm welding widths using old and new anvil wheels with and without cooling air. A lapped type of seam was applied under full factorial design. A microstructure was captured to examine the formation of welding joints, and seam tensile properties were determined. Comparative analysis of comparable welding parameters was analyzed for a gap against pressure and amplitude against power. The actual weld phenomenon was also analyzed based on the recorded machine parameters. The results showed that auxiliary parameters had a significant effect on seam strength. A microscopic image of a welded seam indicated that cooling air reduced the number and size of holes produced. Weld seam with controlled pressure or power provided higher seam strength than that of the controlled gap or amplitude. The actual phenomenon of welding parameters was important to evaluate weld seam quality, whereby the obtained results indicated good quality at lower power and pressure.

Based on 3D virtual fitting technology, this paper simulates and reproduces the fabric patterns and sewing processes of 12 characters’ costumes in different scenes on the basis of completing the archaeology of the characters’ costumes in the painting, so as to realize the 3D virtual sewing and digital simulation restoration of the characters costumes. This paper draws the style diagram, structure diagram and 3D virtual simulation diagram of the character costumes in the painting. The article further improves the research on the costumes of the Five Dynasties and Ten Kingdoms, which has a certain reference value for the study of ancient character costumes and the promotion of Chinese garment culture. At the same time, it provides a reference for the design of artistic works such as character costumes in film and television and games.

With the development of virtual reality, computer-aided design has shown its strength in the garment product development process. Wrist position corresponds to the styloid process of the ulna (SPU). Due the problem that the SPU position is usually not the finest position of the forearm, the wrist position identification in the 3D clothing design is quite important. This paper proposes a method that uses a fixed-step search algorithm based on existing proportion methods to determine the position of the SPU. The accuracy and efficiency of the proposed method has been validated using 100 samples by comparison with the existing methods. It can be fully applied to a virtual 3D-to-2D garment prototyping process and ensure the automation of this process.

Athletes are often subjected to a great physical strain during training and competition. Sport activities performed in hot and humid conditions may result in different heat illnesses with mild or fatal consequences. Against this background it is important to know the thermal state of athletes during physical activity. This article presents the development of a smart T-shirt for monitoring the thermal status of an athlete. The smart T-shirt was created by embedding an electronic system with temperature and humidity sensors that allows the measurement of temperature and the relative humidity of the microclimate. A smart T-shirt is comfortable, and integrated sensors and electronics do not affect wearing comfort. A good concurrence between the temperature and humidity results from using the smart T-shirt, and thus the medical device was achieved. Data obtained can be of great importance to the sports staff who will be able to monitor the athletes' thermal state during matches and competitions.

The texture of a fabric can be perceived by the haptic and visual senses. Visual texture can be defined as a visual quality of a surface. It is an important phenomenon because it can be significant in many fields, such as textile design and e-commerce. At the same time, when we consider the semantics of the word, it is important to take into account that there are a variety of manifestations of fabrics (e.g., woven, knitted, etc.). The mechanism of visual texture perception of fabrics was investigated by measuring visual evaluation values. In our experiment, 12 textile samples with different surface textures are evaluated using thirty-four adjectives (Kansei words). For each visual texture, the adjectives with the highest mean ratings are extracted and analyzed. By using Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA), we aimed to discover and determine preferences for the visual texture of fabrics. The result is a semantic explanation of fabric texture with the adjectives proposed, which can help customers to evaluate the quality of the textile.

This study aims to investigate the characteristics of heat transfer and its mechanism for styling a design garment differently, and to improve thermal comfort caused by clothing styling design, a computational fluid dynamics (CFD) approach has been used to perform numerical investigations of fluid flow and heat transfer across a clothing air gap. Relationships between the heat transfer from the body to clothing (computed by heat transfer equations) and the air gap were examined by body heat loss of different styles of garments. Also, the clothing temperature distribution of different garments was obtained and compared. Computed results reveal that the air gap can play a central role in the heat transfer from the body to the surface of different style garments. When the air gap is small enough, namely about 5 mm in the chest and bust of the X-type of clothing, the conductive heat flux can transfer through the air gap and reach the cloth surface easily, which will bring about the increase of temperature on the clothing surface. The decreasing air gap distance from 50 mm (O-type) to 10 mm (X-type) increases the convective heat flux by up to 25% on the waist. However, the airspeed will increase to greater numbers while the air gap decreases to narrow channels, and it will bring about fierce forced convection heat flux. So the heat transfer must be considered in the process of garment design, and the air gap should be kept at a suitable level. These findings can be used to improve the clothing’s thermal comfort or optimize the cloth structure.

It is a novel approach to design the partition structure of clothing according to the deformation of the human body surface skin during exercise. The functional evaluation of these products remains unknown, and there is limited knowledge about the effects of the partition structure design on the pressure comfort of clothing. This research carried out a partitioned structural design of the leggings based on the skin deformation of the lower limbs of the human body during yoga exercise and developed two styles of seamless yoga leggings. The skin pressure exerted by the new seamless yoga leggings was compared with two commercial yoga leggings. Eight female college students were invited to wear all the yoga leggings samples and perform yoga exercises. The skin pressure exerted by yoga leggings was measured by the German novel-Pliance multipurpose pressure distribution measurement system on 10 body positions. The results showed that yoga leggings designed with a partitioned structure exert a comfortable pressure on the skin during yoga exercise, and the pressure change was smaller under different yoga postures, which has better pressure stability. The partition structure design model of seamless yoga leggings was optimized, which provided a reference for the functional partition design and product development of seamless yoga leggings.

The rapid development of the textile industry has led to the demand for more advanced textile equipment because the current covering yarn machines are large and expensive and have a large physical footprint. Also, the current technology is unsuitable for most laboratory research and small factory proofing. In this paper, the principle of forming covered yarn is analyzed and simplified in three systems: the unwinding system, the covering system, and the winding system. A small sample of low volume and better flexibility is developed, the production process and primary structure of the covered yarn prototype are introduced, and the covering effect of the small prototype is debugged and analyzed.