Welding Metallurgy of

The work reviews the research and development status of magnesium alloy, with more attention to the methodologies and technologies adopted to improve the properties of AZ91 alloy. The drive force of utilizing magnesium alloys for automotive and biomedical application is light weightiness and biocompatibility respectively. However, the softness and high activity of magnesium alloys result in high wear and high corrosion rate respectively. One of the essential factors influencing the properties of magnesium alloy is its microstructure. Consequently, the grain size, morphology and distribution of phase constituents influence the properties of magnesium alloys. The modification of microstructure through processing route (hot working and cold working), heat treatment, and alloying elements improves the mechanical, corrosion, biocompatible, and tribological properties of magnesium alloys. Besides microstructural modification processes, addition of reinforcements, and coatings improves the properties of magnesium alloys. This article emphasis on the recent research on the technologies to improve the microstructure, hardness, tensile strength, ductility, yield strength, wear resistance, and corrosion resistance of magnesium alloy AZ91. Moreover, this review addresses the key issues hindering the applications of magnesium alloys for structural and biomedical applications.

Research and Development in Magnesium Alloys for Industrial and Biomedical Applications: A Review

Low temperature combustion (LTC) is a recent engine technology that can reduce the oxides of nitrogen (NOx) and soot emissions simultaneously while maintaining higher thermal efficiency. The present review work investigates the performance, emission and combustion characteristics of LTC mode engines. Partially premixed LTC (PPLTC), homogeneous charge compression ignition (HCCI), premixed charge compression ignition (PCCI) and reactivity controlled compression ignition (RCCI) modes are researched under LTC mode. In recent decades, different engine strategies have been employed to reduce exhaust emissions and to enhance thermal efficiency. Exhaust gas recirculation, variable valve timing (VVT), advanced fuel injection technologies are adapted to achieve LTC mode in internal combustion (IC) engines to get improved outcomes. This review highlights the properties of fuels, fuel supply systems, valve actuation mechanisms, engine operating conditions and its effects on the engine characteristics. This review provides a perspective plan to the researchers for enhancing the performance, emission and combustion behavior of an engine by using LTC mode with lower NOx and soot emissions. Among LTC mode engines, RCCI mode engine operates well in 60% load, 60% premixed ratio, 35:1 air-fuel ratio and 56% brake thermal efficiency within the combustion phasing control.

A review on low temperature combustion engines: Performance, combustion and emission characteristics

A literature review of fuel effects on performance and emission characteristics of low-temperature combustion strategies

Effect of spirulina microalgae biodiesel enriched with diesel fuel on performance and emission characteristics of CI engine

An experimental study on the performance and emission characteristics of PCCI-DI engine fuelled with diethyl ether-biodiesel-diesel blends

Investigation on performance and emissions of RCCI dual fuel combustion on diesel - bio diesel in a light duty engine

Investigation on reduction of emission in PCCI-DI engine with biofuel blends

Friction stir welding (FSW) is a solid state welding process with potential to join materials that are non weldable by conventional fusion welding techniques. The study of heat transfer in FSW aids in the identification of defects like flash, inadequate heat input, poor material flow and mixing etc. In this paper, transient temperature distribution during FSW of aluminum alloy AA6061-T6 was simulated using finite element modelling. The model was used to predict the peak temperature and analyse the thermal history during FSW. The effect of process parameters namely tool rotation speed, tool traverse speed (welding speed), shoulder diameter and pin diameter of tool on the temperature distribution was investigated using two level factorial design. The model results were validated using the experimental results from the published literature. It was found that peak temperature was directly proportional to tool rotation speed and shoulder diameter and inversely proportional to tool traverse speed. The effect of pin diameter on peak temperature was found to be trivial.

https://iopscience.iop.org/article/10.1088/1757-899X/149/1/012208/pdf

S Thirumalini

Papers

An experimental study on the performance and emission characteristics of PCCI-DI engine fuelled with diethyl ether-biodiesel-diesel blends

Investigation on performance and emissions of RCCI dual fuel combustion on diesel - bio diesel in a light duty engine

Investigation on reduction of emission in PCCI-DI engine with biofuel blends

Numerical modelling of thermal phenomenon in friction stir welding of aluminum plates

Investigations on metallurgical and mechanical properties of CO2 laser beam welded Alloy 825