The present work deals with assessment of heat treated AISI 1020, a low carbon steel (0.2%-C), on the basis of various destructive testing and microstructural behaviour. The steels samples were heated above the lower critical temperature range, i.e. up to 750°C. The cooling rate of all the samples was different. Mainly, three different cooling medium were taken. They are: water, air and sand. These three heat treated samples were compared with as received sample. Hence the final condition of all the four samples is: as received; normalised; sand cooled; water quenched. After a proper preparation, samples were undergone through various mechanical tests, such as, tension test, shear test, hardness test, and impact test. In addition, the microstructural images, captured by an optical microscope, of all the samples were observed and analysed. The mechanical properties and microstructural attributes obtained in ‘heat treated’ samples were compared with those results of ‘as received’ samples. From the present experimental analysis, it was found that heat treatment processes significantly changed/improved the desired properties of the AISI 1020 steel samples.

Purpose: Titanium (Ti) alloys are in high demand in manufacturing industries all over the world. The property like high strength to weight ratio makes Ti alloys highly recommended for aerospace industries. Ti alloys possess good weldability, and therefore, they were extensively investigated with regard to strength and metallurgical properties of welded joint. This study aims to deal with the analysis of strength and microstructural changes in Ti-6Al-4V (Grade 5) alloy after tungsten inert gas (TIG) welding.Design/methodology/approach: Two pair of Ti alloy plates were welded in two different voltages, i.e. 24 and 28 V, with keeping the current constant, i.e. 80 A It was a random selection of current and voltage values to check the performance of welded material. Both the welded plates were undergone through some mechanical property analysis like impact test, tensile test and hardness test. In addition, the microstructure of the welded joints was also analyzed.Findings: It was found that hardness and tensile properties gets improved with an increment in voltage, but this effect was reverse for impact toughness. A good corroboration between microstructure and mechanical properties, such as tensile strength, hardness and toughness, was reported in this work. Heat distribution in both the welded plates was simulated through ANSYS software to check the temperature contour in the plates.Originality/value: A good corroboration between microstructure and mechanical properties, such as tensile strength, hardness and toughness, was reported in this study.

WC-Co based tools are widely used in the field of coal and rock excavation because of their unique combination of strength, hardness, and resistance to abrasive wear. Conical pick is one of the coal cutting tools. The tip of the pick is made of WC-Co material. As coal and rock are heterogeneous elements, they pose various constraints during excavation. As a result the tools wear out during the process. Other parameters like cutting techniques, tool orientation, and environmental conditions also affect the tool significantly. The wearing phenomenon greatly reduces the service life of the tools and thereby cuts down the production rate. To prevent such wearing process, it is important to investigate the different wear mechanisms in WC-Co. Simultaneously, there has to be an ongoing endeavour for the development of better quality WC-Co. This paper focuses on different wear mechanisms in a conical pick which has been used in a continuous miner machine for coal cutting. The worn out surface has been observed by using FE-SEM (field emission scanning electron microscopy) and EDS (energy dispersive X-ray spectroscopy). The mechanisms, namely, coal/rock intermixing, cracking and crushing of WC grains, and adhesion of rock particles, have been predominantly investigated in this study. A little indication of corrosive decay in the WC grain has also been reported. The EDS has detected material concentration in a selected area or point of the worn-out surface. The spectrograph confirms the presence of coal/rock materials. Elements such as W, C, Ca, K, O, and Co have been mainly found in different concentrations at different positions.