Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Topic Review
Semiconductor Gas Sensors
Semiconductor materials include metal oxides, conducting polymers, carbon nanotubes, and 2D materials. Metal oxides are most often the first choice due to their ease of fabrication, low cost, high sensitivity, and stability. Some of their disadvantages are low selectivity and high operating temperature. Conducting polymers have the advantage of a low operating temperature and can detect many organic vapors. They are flexible but affected by humidity. Carbon nanotubes are chemically and mechanically stable and are sensitive towards NO and NH3, but need dopants or modifications to sense other gases. Graphene, transition metal chalcogenides, boron nitride, transition metal carbides/nitrides, metal organic frameworks, and metal oxide nanosheets as 2D materials represent gas-sensing materials of the future, especially in medical devices, such as breath sensing.
  • 2.4K
  • 10 Dec 2020
Topic Review
Twinning-Induced Plasticity
Twinning-induced plasticity (TWIP) steel is a second-generation advanced high strength steel grade developed for automotive applications. TWIP steels exhibit an excellent combination of strength and ductility, mainly originating from the activation of deformation twinning.
  • 2.1K
  • 23 Feb 2021
Topic Review
Nickel-Copper Alloys
Nickel-Copper (Ni-Cu) alloys exhibit simultaneously high strength and toughness (particularly, at cryogenic temperatures), excellent corrosion resistance, and may show good wear resistance. Therefore, they are widely used for manufacturing of (i) structural components of equipment in the chemical, oil, and marine industries, (ii) resistors and contacts in electrical and electronic equipment, (iii) corrosion resistant coatings, and (iv) fuel cells. Processing technologies includes bar forging, plate and tube rolling, wire drawing, heat treatment (for certain alloy compositions), powder and wire arc additive manufacturing, electrodeposition.
  • 2.0K
  • 26 Oct 2020
Topic Review
Titanium Aluminides
Titanium aluminides (TiAl) have the potential of substituting nickel-based superalloys (NBSAs) in the aerospace industries owing to their lightweight, good mechanical and oxidation properties. Functional simplicity, control of sintering parameters, exceptional sintering speeds, high reproducibility, consistency and safety are the main benefits of spark plasma sintering (SPS) over conventional methods. Though TiAl exhibit excellent high temperature properties, SPS has been employed to improve on the poor ductility at room temperature. Powder metallurgical processing techniques used to promote the formation of refined, homogeneous and contaminant-free structures, favouring improvements in ductility and other properties are discussed. This article further reviews published work on phase constituents, microstructures, alloy developments and mechanical properties of TiAl alloys produced by SPS. Finally, an overview of challenges in as far as the implementation of TiAl in industries of interest are highlighted.
  • 1.7K
  • 07 Jan 2021
Topic Review
Super Duplex Stainless Steel
In this present study, the influence of isothermal aging temperature and duration on microstructural and mechanical properties of a hot-deformed UNS S32750 Super Duplex Stainless Steel (SDSS) alloy was investigated by SEM-EBSD (Scanning Electron Microscopy-Electron Backscatter Diffraction) and tensile testing techniques. An isothermal aging treatment, at temperatures between (400 - 600)°C and treatment duration between (3 - 120)h, was applied to a commercial UNS S32750 SDSS alloy. Microstructural characteristics of all thermo-mechanical (TM) processed states, such as distribution and morphology of constituent phases, grain’s modal orientation (MO) and, obtained mechanical properties were analysed correlated with the TM processing conditions. Obtained experimental results show that the constituent phases, in all TM processed states, are represented by delta- and gamma-phases. SEM-EBSD analysis revealed microstructural modifications induced by TM processing, showing elongated gamma-phase grains within delta-phase matrix. Within the delta-phase matrix, dynamically recrystallized grains were identified as a result of applying hot deformation and isothermal aging treatments. Also, it was observed that aging treatment parameters can significantly influence the mechanical behaviour exhibited by the UNS S32750 SDSS alloy, in terms of elongation to fracture and absorbed energy during impact testing.
  • 1.6K
  • 29 Oct 2020
Topic Review
Ironmaking Process
Fe is extracted from Fe ore and converted into alloys. This metallurgical process is important. The raw materials of the iron-bearing mineral are introduced in the blast furnace (BF), wherein aside from Fe and C, other elements are also subjected to roasting in the furnace.
  • 1.6K
  • 10 Mar 2021
Topic Review
Intermediate Strain Rate Testing Devices
The existing experimental tests are mainly designed to study the mechanical response of materials at various strain rates. Many researchers performed the experimental test in tension, compression, and shear (with torsion test) over a wide range of strain rates. They found out that material exhibits an increase in yield stress as well as flows stress with an increase in strain rate. It illustrates that there is a need for experimental data to study the material behaviour over the full range of strain rates, from quasi-static to high strain rate test. Many special techniques have been developed to bridge the strain rate gap between quasi-static and high strain rate testing to provide a method for an intermediate strain rate test for engineering materials. Some researchers have tried to conduct intermediate strain rate tests with standard servo-hydraulic load frames. However, the results of such tests are not accurate. The problem is that during the experiment, the whole machine is not in static equilibrium. The inertial effect influences the experimental data. The records obtained from these machines are often noisy with large oscillation. therefore, the comprehensive review is given to describes the development and evolution of the existing intermediate strain rate testing devices which includes the working principles, some critical theories, technological innovation in load measurement techniques, components of the device, basic technical assumption, and measuring techniques. In addition, some research direction on future implementation and development of an intermediate strain rate apparatus is also discussed in detail.
  • 1.5K
  • 18 Apr 2021
Topic Review
TIG-MIG Hybrid Welding
Tungsten inert gas-metal inert gas hybrid welding (TIG-MIG) combines the advantages of tungsten and metal inert gas welding. It can efficiently produce high-quality weld joints that meet modern manufacturing quality and efficiency requirements. Based on heat transfer, fluid dynamics, and electromagnetic theory, a three-dimensional coupled transient model of arc-droplet interactions in TIG-MIG hybrid welding was established. In this study, the temperature field, flow field, electromagnetic force, pressure, and current density parameters were analyzed in the arc space. The results show that introducing TIG welding has a significant impact on MIG welding.
  • 1.4K
  • 13 Jan 2021
Topic Review
Perylene-Based Non-Fullerene Acceptors
Perylene has had a tremendous impact in the history of material research for the molecular semiconductors. Among numerous derivatives of this polyaromatic hydrocarbon, perylene diimide (PDI) represents a promising class of organic materials envisioned as non-fullerene acceptors (NFAs) for the practical organic photovoltaic (OPV) applications due to their enhanced photo- and thermal stability and remarkably high electron affinity, some of which realize band-like transport properties. The present review guides some of the representative achievements in the development of rationally designed PDI systems, highlighting synthetic methodologies based on bay-functionalization strategies for creating well-designed molecular nanostructures and structure-performance relationship of perylene-based small molecular acceptors (SMAs) for the photovoltaic outcomes.
  • 1.2K
  • 28 Oct 2020
Topic Review
Microalloyed Niobium Steel
Thermomechanical processing of niobium microalloyed steel was performed with the purpose of determining the interaction between niobium precipitates and dislocations, as well as determining the influence of the temperature of final deformation on the degree of precipitation and dislocation density. Two variants of thermomechanical processing with di erent final rolling temperatures were carried out. Samples were studied using electrochemical isolation with an atomic absorption spectrometer, transmission electron microscopy, X-ray di raction analysis, and universal tensile testing with a thermographic camera. The results show that the increase in the density of dislocations before the onset of intense precipitation is insignificant because the recrystallization process takes place simultaneously. It increases with the onset of strain-induced precipitation. It is shown that niobium precipitates determine the density of dislocations. The appearance of Lüders bands was noticed as a consequence of the interaction between niobium precipitates and dislocations during the subsequent cold deformation. In both variants of the industrial process performed on the cold deformed strip, Lüders bands appeared.
  • 1.2K
  • 26 Oct 2020
  • Page
  • of
  • 5
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Feedback