http://nopr.niscpr.res.in/handle/123456789/44930 2026-10-10T21:13:14Z http://nopr.niscpr.res.in/handle/123456789/44939 Title: Effect of induction heated friction stir welding on corrosive behaviour, mechanical properties and microstructure of AISI 410 stainless steel Authors: Mohan, Dhanesh G; Gopi, S; Rajasekar, V Abstract: In the current scenario, the industry requires a joining or welding method, which does not produce any environmental hazards. Friction stir welding (FSW) is the future of all metal joining methods because FSW does not produce any harmful byproducts and it enhances the joining strength too. The main limitation of friction stir welding was the difficulty to weld hard metals. The tool damage is very high while welding hard metals. These problems happen while using FSW can be recovered by using an additional heating source such as induction heating, arc heating or resistance heating. The induction heating is the quickest heating method as well as an economic method compared to other heating methods. AISI 410 stainless steel (SS) plate is difficult to weld by conventional welding methods, due to the glassy surface and this glassy surface cause sputtering. AISI 410 SS is chosen for this work and welded by using induction heated friction stir welding method (IH-FSW). The tool used for welding AISI 410 SS is made by using tungsten carbide with a hexagonal profile. A sound joint is fabricated at a spindle speed of 1200 rpm, welding speed of 45 mm/min, plunge depth of 0.05 mm and an additional heat input by using the induction-heating coil is about 100°C at 50 W power respectively. Page(s): 203-208 2018-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/44938 Title: Multistage cup drawing of AISI 1040 graded medium carbon steel Authors: Parida, A K; Soren, S; Jha, R N; Krishnamurthy, N Abstract: In this paper a new modified processing route, as an innovative approach, has been proposed for producing cylindrical cups from thicker circular blanks, like 12 mm thick and 60 mm diameter. Rolled strips of aluminium (Al)-killed AISI 1040 graded medium carbon steel in hardened and tempered condition was used as an alternative high strength material. The processing route mainly consisted of pre-forming of flat blanks to a little draw in shape, followed by multistage deep drawing accompanied with wall ironing held without blank-holders and with inter-stage stress relief annealing. Thus, evolution of different processing effects such as cup dimension and cup quality, wall thickness distribution profiles, drawability and ironability parameters, strain distribution profiles, spring back tendency of cups in terms of residual hoop stress distributions, and microstructures at cup wall zones, were obtained and discussed. Page(s): 209-216 2018-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/44937 Title: Numerical simulation of thermal fracture in coatings using element free Galerkin method Authors: Garg, Sahil; Pant, Mohit Abstract: The work presented, broadens the adeptness of element free Galerkin method (EFGM) for analysis of thermal fracture in case of materials with coatings under plane stress conditions. A modeling approach has been used by clubbing jump function approach with enrichment criterion in order to model multiple weak and strong discontinuities in the domain. The weak discontinuity, i.e., the interface of two materials is modeled via a jump function methodology. The stress fields around the crack tip are modeled using intrinsic enrichment criterion. Modified interaction integral scheme for thermal fracture has been put to use for generating mode-I stress intensity factors (SIFs). The effect of mechanical properties on crack under sudden temperature change is compared using three cases in which zinc and steel substrates are used (steel/zinc/steel configuration and zinc/steel/zinc configuration) and compared with results of mono-material configuration. Page(s): 217-232 2018-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/44936 Title: Study of hardness and wear behavior of surface modified AA 7075 with tungsten carbide using GTA as a heat source Authors: Abhinavaram, J; Shanmugasundaram, A; Prashanth, R; Jagadeesh, S; Arul, Sanjivi; Sellamuthu, R Abstract: The aim of this work is to evaluate the role of tungsten carbide (WC) in increasing the hardness and improving the wear resistance of AA 7075 alloy. WC is reinforced into the surface of AA 7075 by using gas tungsten arc (GTA) as a heat source. Some of the GTA process parameters are maintained as constant, viz, contact-to-work distance and electrode tip angle, whereas the heat source current and the work speed are varied. With reference to the proper fusion of base metal, optimum GTA heat source parameter is finalized based on a number of trials. It is found that the hardness is reduced after the application of heat. To improve the properties, the alloy is subjected to heat treatment which included solution treatment, water quenching, and artificial aging. The hardness and wear behavior of the WC reinforced surface composite resulted in a positive trend. A comprehensive study on the microstructure of AA 7075 at different stages of the work is done using optical microscopy (OM), scanning electron microscopy (SEM), EDX analysis and X-ray diffraction (XRD). Page(s): 233-242 2018-06-01T00:00:00Z