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The purpose of this study is to review and summarise the existing available literature on lightweight cladding systems to provide detailed information on fire behaviour (ignitibility, heat release rate and smoke toxicity) and various test method protocols. Additionally, the paper discusses the challenges and provides updated knowledge and recommendation on selective-fire mechanisms such as rapid-fire spread, air cavity and fire re-entry behaviours due to dripping and melting of lightweight composite claddings.

A comprehensive literature review on fire behaviour, fire hazard and testing methods of lightweight composite claddings has been conducted in this research. In summarising all possible fire hazards, particular attention is given to the potential impact of toxicity of lightweight cladding fires. In addition, various criteria for fire performance evaluation of lightweight composite claddings are also highlighted. These evaluations are generally categorised as small-, intermediate- and large-scale test methods.

The major challenges of lightweight claddings are rapid fire spread, smoke production and toxicity and inconsistency in fire testing.

The review highlights the current challenges in cladding fire, smoke toxicity, testing system and regulation to provide some research recommendations to address the identified challenges.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

This article comprises Chapter 6 from the recently published book ‘An Engineer’s Guide to Flexible Circuit Technology by J. Fjelstad

Attempts to reveal some of the factors that might cause measurement and evaluation errors in dry sliding. Discusses matters such us “what” and “how” is simulated and “why” and “what” is really measured and suggests ways to tackle these matters. Presents means of avoiding measurement errors as well as suitable testing procedures. Suggests a strategy of experimental work that encompasses the needs of both pure research and engineering design. It was found that the pin‐on‐disc test largely satisfies the conditions for a good simulation of certain engineering applications while providing a wealth of data for both scientific insight and engineering design.

This paper aims to present the methodology and results of the experimental characterization of three-dimensional (3D) printed acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) parts utilizing digital image correlation (DIC).

Tensile and shear characterizations of ABS and PC 3D-printed parts were performed to determine the extent of anisotropy present in 3D-printed materials. Specimens were printed with varying raster ([+45/−45], [+30/−60], [+15/−75] and [0/90]) and build orientations (flat, on-edge and up-right) to determine the directional properties of the materials. Tensile and Iosipescu shear specimens were printed and loaded in a universal testing machine utilizing two-dimensional (2D) DIC to measure strain. The Poisson’s ratio, Young’s modulus, offset yield strength, tensile strength at yield, elongation at break, tensile stress at break and strain energy density were gathered for each tensile orientation combination. Shear modulus, offset yield strength and shear strength at yield values were collected for each shear combination.

Results indicated that raster and build orientations had negligible effects on the Young’s modulus or Poisson’s ratio in ABS tensile specimens. Shear modulus and shear offset yield strength varied by up to 33 per cent in ABS specimens, signifying that tensile properties are not indicative of shear properties. Raster orientation in the flat build samples reveals anisotropic behavior in PC specimens as the moduli and strengths varied by up to 20 per cent. Similar variations were observed in shear for PC. Changing the build orientation of PC specimens appeared to reveal a similar magnitude of variation in material properties.

This article tests tensile and shear specimens utilizing DIC, which has not been employed previously with 3D-printed specimens. The extensive shear testing conducted in this paper has not been previously attempted, and the results indicate the need for shear testing to understand the 3D-printed material behavior fully.

The purpose of this paper is to characterize the material properties of carbon fiber polyamide composite (CFPC) used in a 3D rapid prototyping process based upon selective laser sintering (SLS) and demonstrate that the SLS process introduces a bias in the micro‐fiber orientation such that the CFPC solid is an orthotropic structural material.

Material coupons for tensile tests from each of the orthogonal planes are created using the SLS process. After tensile testing, the coupons are examined under scanning electron microscopy to verify the micro‐fiber orientation bias. A complex 3D structure developed utilizing the CFPC material is subjected to modal testing to extract the natural frequencies. These frequencies are compared to predictive numerical analysis results from computer‐aided engineering (CAE) software to validate the coupon test results.

This paper proves that the CFPC solid material is orthotropic after the SLS process and that the process itself creates bias in the micro‐fiber orientation. Predictions of natural frequencies from CAE software for a complex 3D structure created from CFPC are within 2 percent of the actual natural frequencies determined during modal testing.

The paper has determined the tensile material characteristics of solid CFPC correcting the original material data sheet information which lists the solid CFPC as isotropic with much stronger tensile characteristics. It has also provided evidence of the bias that SLS introduces to embedded micro‐fibers during the rapid‐prototyping process.

The paper deals with experimental work on determining the material characteristics of a relatively new composite material for which very little test data exists in literature. In particular, an original contribution is demonstration of the micro‐fiber orientation bias introduced by the SLS process.

THE occurrence of isolated fires in commercial, passenger carrying aircraft has focused considerable attention upon the fire risks involved in the use of combustible materials, the arrangement of functional equipment and accessories, and the effectiveness of fire‐proof finishes and coatings. In addition to other studies concerning the elimination of fire hazard through careful survey of the electrical system and other functional systems, studies have been made concerning the improvement of the ignition resistance of materials and the subsequent propagation of fire. Serious fires have developed as a result of propagation by materials which were not responsible for the original ignition of fire. An intensive effort has been made to reduce this fire hazard by the development and application of protective coatings and finishes to vulnerable and combustible materials. This work led to the obvious need for, and development of, a testing apparatus by which a realistic comparison could be made of combustible materials under conditions simulating those of an actual fire.

The purpose of this paper is to characterize mechanical properties (tensile, compressive and flexural) for the three-dimensional printing (3DP) process, using various common recommended infiltrate materials and post-processing conditions.

A literature review is conducted to assess the information available related to the mechanical properties, as well as the experimental methodologies which have been used when investigating the 3D printing process characteristics. Test samples are designed, and a methodology to measure infiltrate depths is presented. A full factorial experiment is conducted to collect the tensile, compressive and bending forces for a set of infiltrates and build orientations. The impact of the infiltrate type and depth with respect to the observed strength characteristics is evaluated.

For most brittle materials, the ultimate compression strength is much larger than the ultimate tensile strength, which is shown in this work. Unique stress–strain curves are generated from the infiltrate and build orientation conditions; however, the compressive strength trends are more consistent in behavior compared to the tensile and flexural results. This comprehensive study shows that infiltrates can significantly improve the mechanical characteristics, but performance degradation can also occur, which occurred with the Epsom salts infiltrates.

More experimental research needs to be performed to develop predictive models for design and fabrication optimization. The material-infiltrate performance characteristics vary per build orientation; hence, experimental testing should be performed on intermediate angles, and a double angle experiment set should also be conducted. By conducting multiple test scenarios, it is now understood that this base material-infiltrate combination does not react similar to other materials, and any performance characteristics cannot be easily predicted from just one study.

These results provide a foundation for a process design and post-processing configuration database, and downstream design and optimization models. This research illustrates that there is no “best” solution when considering material costs, processing options, safety issues and strength considerations. This research also shows that specific testing is required for new machine–material–infiltrate combinations to calibrate a performance model.

There is limited published data with respect to the strength characteristics that can be achieved using the 3DP process. No published data with respect to stress–strain curves are available. This research presents tensile, compressive and flexural strength and strain behaviors for a wide variety of infiltrates, and post-processing conditions. A simple, unique process is presented to measure infiltrate depths. The observed behaviors are non-linear and unpredictable.

This study aimed to compare the performance of sustainable shoes made with bacterial cellulosic composite and commercial leather shoes using an experimental research design. The two specific research objectives were: (1) to examine the basic material properties of multi-layered bacterial cellulosic materials (MBC), which include green tea-based cellulosic (GBC) mats, hemp fabrics, and denim fabrics, in comparison with those of two-layered leathers (MCP) consisting of calf-skin and pig-skin – commonly used in shoe manufacturing; and (2) to explore wearers’ performance in the two types of shoes by assessing quantitative kinematic and kinetic parameters of lower body movements.

This study focused on assessing the basic materials testing and performance of sustainable shoes through a biomechanical approach, in contrast to commercially available leather shoes, through human wear trials. In this study, green tea-based cellulosic (GBC) mats were developed using the optimal combination of ingredients for cellulose growth. Subsequently, the GBC, denim fabric (100% cotton), and 100% hemp fabric were combined to create multi-layered bacterial cellulosic materials (MBC) as an alternative to leather. Additionally, calf-skin and pig-skin leathers were utilized to produce a commercially available two-layered leather (MCP), commonly employed in shoe manufacturing. 37 of the 42 human subjects who participated in wear testing were collected. A paired t-test was conducted to determine whether significant mean differences existed between the two shoe types, a paired t-test was conducted.

To develop a biodegradable and compostable material that could be used as a leather alternative for the footwear industry, we proposed MBC and examined its properties compared with those of MCP, a product often used when making shoes. These findings confirmed the similar properties of MBC and MCP from the material testing and the possibility of using a men’s sustainable shoe prototype as a leather alternative, in terms of kinematics and kinetics.

The new multi-layered bacterial cellulosic materials (MBC) could be an alternative to commercial leathers such as innovative sustainable material construction, advanced design, and advanced techniques to optimize the overall performance of sustainable footwear.

Investigating the integration of smart textile technologies, ergonomic design principles, and personalized customization will contribute to developing MBC and making sustainable shoes using MBC compared with commercial leather shoes. This study provides valuable insights into further refinement and innovation in the sustainable footwear industry.

Surface insulation resistance (SIR) testing is used in a number of ways to characterise residues or determine the effect of residues on the performance of printed wiring boards (PWBs) and assemblies (PWAs). Stated simply, SIR testing is the measurement of leakage currents on or in a substrate, usually during exposure to elevated temperature and humidity conditions, for a varying amount of exposure time. An examination of the resistance trends over time, and occurrences of metal migration and/or corrosion, can determine the potential threats of compatibility problems with circuit card assembly materials. This paper examines how SIR testing is used in various areas, with an emphasis on the design of the SIR test vehicle. With the advent of ANSI‐J‐STD‐001B, more companies will need to design their own test vehicle for process qualification.