Showing papers in "Materials Science and Technology in 2019"
TL;DR: In this paper, the mechanism of long-lasting luminescence has been a popular area of research in the field of persistent afterglow material, which can intensively glow up to 20'h.
Abstract: Ever since the discovery of SrAl2O4:Eu,Dy persistent afterglow material, that can intensively glow up to 20 h, the mechanism of long-lasting luminescence has been a popular area of research. The re...
61 citations
TL;DR: In this paper, the effect of different types of fibres named polypropylene (PP), polyvinyl alcohol (PVA), carbon and glass fibres on the fresh and hardened properties of geopolymers is reviewed.
Abstract: Recently, the inclusion of different types of fibres into geopolymers, as reinforcement, has amplified due to the rapid increase in geopolymers developments In spite of geopolymers have prospective properties such as low carbon footprint, low consumption of energy, good compressive strength, resistance to fire, resistance to flame, resistance to corrosion and good durability, they undergo from low tensile strength and flexural strength To avoid these shortages, different types of fibres could be incorporated into geopolymers to enhance their toughness, tensile strength and ductility The current survey aims to review the effect of different types of fibres named polypropylene (PP), polyvinyl alcohol (PVA), carbon and glass fibres on the fresh and hardened properties of geopolymers
56 citations
TL;DR: In this paper, the authors discuss the importance of steel, aluminium and magnesium in engineering materials owing to their excellent mechanical properties, however, their applications are limited due to inadequate corrosion resistance.
Abstract: Steel, aluminium and magnesium are important engineering materials owing to their excellent mechanical properties. However, their applications are limited due to inadequate corrosion resistance. Va...
51 citations
TL;DR: In this article, non-destructive evaluation (NDE) is played an important role in three-dimensional printing/digital or additive manufacturing, which is an area that is taking off with considerable rapidity and magnitude.
Abstract: Three-dimensional printing/digital or additive manufacturing is an area that is taking off with considerable rapidity and magnitude. In the same time, non-destructive evaluation (NDE) is playing an...
44 citations
TL;DR: In this article, a martensitic microstructure is used to ensure hardness, which correlates with better wear performance, but in practice the steel may be subjected to abrasion.
Abstract: Many abrasion resistant steels rely on a martensitic microstructure to ensure hardness, which in general correlates with better wear performance. However, in practice the steel may be subjected to ...
41 citations
TL;DR: In this paper, the process of martensitic α′(α) phase decomposition in titanium alloys has not been sufficiently characterised in the literature, especially in terms of plastically deformed martensite.
Abstract: The process of martensitic α′(α″) phase decomposition in titanium alloys has not been sufficiently characterised in the literature – especially in terms of plastically deformed martensite. ...
39 citations
TL;DR: In this paper, a study of shoulder friction stir processing of high strength thick AA7075 aluminium alloy demonstrated tiny gradient in the microstructure refinement across the thickness, which was attributed to...
Abstract: Stationary shoulder friction stir processing of high strength thick AA7075 aluminium alloy demonstrated tiny gradient in the microstructure refinement across the thickness, which was attributed to ...
38 citations
TL;DR: In this paper, a structural supercapacitor with activated carbon fabric electrodes and a solid composite electrolyte, consisting of organic liquid electrolyte 1 M TEABF4 in propylene carbonate and an epoxy matrix where different compositions were considered of 1:2, 1:1 and 2:1 w/w epoxy, was considered.
Abstract: This paper presents investigations to create a structural supercapacitor with activated carbon fabric electrodes and a solid composite electrolyte, consisting of organic liquid electrolyte 1 M TEABF4 in propylene carbonate and an epoxy matrix where different compositions were considered of 1:2, 1:1 and 2:1 w/w epoxy: liquid electrolyte. Vacuum-assisted resin transfer moulding was used for the impregnation of the electrolyte mixture into the electrochemical double layer capacitor (EDLC) assembly. The best electrochemical performance was exhibited by the 1:2 w/w epoxy: liquid electrolyte ratio, with a cell equivalent-in-series resistance of 160 cm2 and a maximum electrode specific capacitance of 101.6 mF g-1 while the flexural modulus and strength were 0.3 GPa and 29.1 MPa, respectively, indicating a solid EDLC device.
36 citations
TL;DR: In this paper, powder bed fusion techniques for additive layer manufacturing (ALM) are reviewed with a focus on titanium alloys production and selective laser melting and electron beam melting are discussed.
Abstract: Powder bed fusion (PBF) techniques for additive layer manufacturing (ALM) are reviewed with a focus on titanium alloys production. Selective laser melting and electron beam melting are discussed in...
33 citations
TL;DR: In this article, a carbon black conductive filler material was added to specially designed polyurethane polymer to prepare shape memory polymer nanocomposites, which has e cient properties.
Abstract: Carbon black conductive filler material, 2–40% by weight was added to specially designed polyurethane polymer to prepare shape memory polymer nanocomposites. The synthesised polyurethane (PU) has e...
33 citations
TL;DR: The low-temperature trend of solid oxide fuel cells is necessary for its commercialisation as mentioned in this paper, and the electrolyte materials with excellent properties at low and intermediate temperatures are needed for its development.
Abstract: The low-temperature trend of solid oxide fuel cells is necessary for its commercialisation, and the electrolyte materials with excellent properties at low and intermediate temperatures, whi...
TL;DR: In this article, the authors studied the effect of high-temperature homogenization on the grain growth and mechanical properties of CrMnFeCoNi high-entropy alloys (HEAs) and showed that the relationship between yield stress and grain size follows the Hall-Petch dependence with a higher intrinsic strength.
Abstract: Homogenisation has been used to eliminate solute segregation of CrMnFeCoNi high-entropy alloys (HEAs) before thermomechanical processing. To overcome the deficiencies caused by high-temperature homogenisation, we cancelled the homogenisation and studied the solute segregation feature and its effect on the grain growth and the mechanical property. The HEA forms equiaxed grains with the solute segregation in the range of tens of micrometres after cold rolling and recrystallisation. The grain growth in recrystallisation still abides by the classical grain growth kinetics, but with a higher power index of 3.33 and activation energy of 392.4 kJ mol−1 than those of the homogenised HEA, indicating a solute-drag effect. The relationship between the yield stress and grain size follows the Hall–Petch dependence with a higher intrinsic strength.
TL;DR: In this paper, the current status of field assisted sintering technology (FAST) of structural metals from powder is critically reviewed, and there have been significant increases in the uptake of FA...
Abstract: The current status of field assisted sintering technology (FAST) of structural metals from powder is critically reviewed. Recently, there have been significant increases in the uptake of FA...
TL;DR: In this article, the authors proposed a method to decrease the platinum loading by increasing its electrocatalytic properties, and showed that platinum materials have shown significant improvement in the surface catalysed chemical transformation pathways in fuel cell technology.
Abstract: Platinum and platinum-based materials with high catalytic performance, and chemical and mechanical stability are vital to electronic devices, biomedical science, optics, petroleum, and automotive industries. Because of the limited supply and high cost of platinum, it is highly desirable to develop new effective methodologies which can decrease the platinum loading by increasing its electrocatalytic properties. Depending upon their size, shape, and morphology, platinum materials have shown significant improvement in the surface catalysed chemical transformation pathways in fuel cell technology. Much research is now focused on the manufacturing and engineering of platinum and platinum-based materials which proffer enhanced catalytic efficiency, and offer chemical and mechanical robustness.
TL;DR: Residual stress fields dynamically fluctuate throughout the manufacturing process of metallic components and are caused by local misfit of a thermal, mechanical or metallurgical nature as mentioned in this paper. But they do not change with temperature.
Abstract: Residual stress fields dynamically fluctuate throughout the manufacturing process of metallic components and are caused by local misfit of a thermal, mechanical or metallurgical nature. Recent adva...
TL;DR: In this article, a laser-based additive manufacturing process was used to achieve good surface quality and low porosity of copper alloys, which is challenging due to the physical properties of copper and its alloys.
Abstract: Owing to the physical properties of copper and its alloys it is challenging to achieve good surface quality and low porosity by the widely used laser-based additive manufacturing processes. This pa...
TL;DR: In this article, the stability of reversed austenite (RA) and its effect on mechanical properties in steel with annealing temperature from 903 to 943 K was elucidated.
Abstract: We elucidate here the stability of reversed austenite (RA) and its effect on mechanical properties in 005C–50Mn steel With increased annealing temperature from 903 to 943 K, the volume f
TL;DR: In this article, simple ordered L12 phase and complex ordered µ phase were found in the (FeCoNiMo)90Al10 alloy, while disordered FCC and µ phases were detected in the FeCoNiMomo)90Cr10 alloy.
Abstract: Simple ordered L12 phase and complex ordered µ phase were found in the (FeCoNiMo)90Al10 alloy, while disordered FCC and µ phases were detected in the (FeCoNiMo)90Cr10 alloy. After annealing...
TL;DR: In this article, the influence of CNTs on the density, microstructure, and strength of SLM CNT-AlSi10Mg composites was investigated.
Abstract: Carbon nanotube (CNT)-AlSi10Mg composites were fabricated by selective laser melting (SLM). The influence of CNTs on the density, microstructure, and strength of SLM CNT-AlSi10Mg composites was inv...
TL;DR: In this article, the effect of post-deposition heat treatment on porosity, microstructure, and mechanical properties of Ti-6Al-4V produced via an Electron Beam Melting process was investigated.
Abstract: This paper investigates the effect of post-deposition heat treatment on porosity, microstructure, and mechanical properties of Ti–6Al–4V produced via an Electron Beam Melting process. Samples were ...
TL;DR: In this article, cenosphere particles embedded in AA2014 aluminium matrix are used to fabricate syntactic foam by stir casting method, the particle size is about 100 µm and foam density is about 1990 µm.
Abstract: In this paper, cenosphere particles embedded in AA2014 aluminium matrix are used to fabricate syntactic foam by stir casting method. The particle size is about 100 µm and foam density is about 1990...
TL;DR: The microstructure and properties of a Cu-Ni-Co-Si alloy were investigated through high-resolution transmission electron microscopy and three-dimensional atom probe analysis after aging at 500°C.
Abstract: The microstructure and properties of a Cu–Ni–Co–Si alloy were investigated through high-resolution transmission electron microscopy and three-dimensional atom probe analysis after aging at 500°C fo...
TL;DR: In this article, a quenching and partitioning (Q&P) treatment was applied to warm stamping of a medium Mn steel to improve the yield strength of auto-parts.
Abstract: A novel application of quenching and partitioning (Q&P) treatment to warm stamping of a warm-rolled medium Mn steel was investigated. The results show that Q&P could improve yield strength of auto-parts from the formation of carbides and twinned martensite, and reduce the yield point elongation for carbon partitioning during Q&P process and a higher dislocation density. Regardless of stamping temperature either the single austenite or dual-phase region, an extraordinary product of strength and ductility (≥24 GPa·%) was achieved, which is two or three times higher than those of hot-stamped boron steels. The combined warm rolling and warm stamping process with Q&P treatment may have potential to implement the application of medium Mn steels for ultrahigh strength-ductile auto-parts.
TL;DR: The global automotive industry has been desperately striving to address the challenge of weight reduction in automobiles in order to decrease the carbon footprint and increase fuel efficiency as mentioned in this paper. But, the challenge has not yet been addressed.
Abstract: The global automotive industry has been desperately striving to address the challenge of weight reduction in automobiles in order to decrease the carbon footprint and increase fuel efficiency. Sinc...
TL;DR: In this article, a stationary shoulder friction stir process (SSFSP) was proposed to produce a smooth surface finish, which contributes to reducing the heat input during friction stir during friction-stirring.
Abstract: We propose a stationary shoulder friction stir process (SSFSP) to produce a smooth surface finish. The use of a stationary shoulder tool contributes to reducing the heat input during friction stir ...
TL;DR: In this paper, a new microstructural design is proposed to develop a strong and ductile quenching and partitioning (Q&P) steel with low yield ratio.
Abstract: A new microstructural design is proposed to develop a strong and ductile quenching and partitioning (Q&P) steel with low yield ratio. This steel has a heterogeneous dual phase microstructure which ...
TL;DR: In this paper, the effects of deformation temperature on phase transformation and microstructure in nanostructured bainite steel were studied and the results indicate that the deformed austenite with a strain of 0.3...
Abstract: The effects of deformation temperature on phase transformation and microstructure in nanostructured bainite steel were studied. The results indicate that the deformed austenite with a strain of 0.3...
TL;DR: In this article, the mechanical behavior and fracture of a Fe-5Mn-2.5Al-0.2C (in wt%) medium Mn steel was studied.
Abstract: The mechanical behaviour and fracture were studied in a Fe–5Mn–2.5Al–0.2C (in wt-%) Medium Mn steel. Metallographic and magnetic measurements confirm the significant influence of the transformation...
TL;DR: In this article, the regulation mechanism of the traditional and emerging surface strengthening treatments, such as mechanical shot peening (SP) and laser shock processing (LSP), is summarized.
Abstract: This paper summarises the regulation mechanism of the traditional and emerging surface strengthening treatments – mechanical shot peening (SP) and laser shock processing (LSP) treatment, re...
TL;DR: In this paper, the microstructural development and mechanical properties of friction stir welded high-entropy alloy were investigated and the stirring process and the air cooling period were separated for discussion.
Abstract: To investigate the microstructural development and mechanical properties of friction stir welded high-entropy alloy, the stirring process and the air cooling period were separated for discussion. T...