http://nopr.niscpr.res.in/handle/123456789/60062 <b>Special issue: Materials and Manufacturing Processes (ICARAE2021)</b> Wed, 07 Oct 2026 16:30:49 GMT 2026-10-07T16:30:49Z http://nopr.niscpr.res.in/handle/123456789/60072 Title: Simplified micromechanics approach to analysis the performance of UD composites Authors: Godara, Surendra Singh; Mahato, Prashanta Kumar; Saxena, Kuldeep Kr Abstract: A simplified micromechanical approach is used for the modelling and analysis of unidirectional (UD) composite performance. In this paper, the influence of volume fraction and constituent properties on the effective longitudinal, transverse, and shear properties of unidirectional composites are investigated. These effective properties are determined using the micromechanical approach, which is based on mathematical modelling using the rule of mixtures. Four different types of unidirectional composites such as T300/BSL914C, IM7/8511-7, T300/PR319, and S2-Glass/epoxy were used for analysis purposes. The method was validated with existing experimental results. The response is dependent on an array of parameters, such as the orientation of fibers, the volume fractions of fibers, array of fibers and the material properties of their constituents. Further, this micromechanical method might be used with other reinforcing fibers for the prediction of properties of UD, hybrid and other composites architectures. Page(s): 299-306 Wed, 01 Jun 2022 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/60072 2022-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/60071 Title: Filler powder free joining of SAF 2507 using selective microwave hybrid heating technique Authors: Singh, Parminder; Prajapati, Deo Raj; Sehgal, Shankar Abstract: Microwave Hybrid Heating (MHH) based joining of super duplex stainless steel (SAF 2507) with cross-sectional dimensions 3.5 mm ×3 mm has been carried out for the first time by using a microwave applicator of 900 W operated at 2.45 GHz for 400 s. Graphite rods have been used instead of traditionally used charcoal powder to serve as susceptor material. Graphite rods are good susceptor of microwave radiations therefore the presence of these rods helps in initiating and carrying forward the joining process. Moreover, the melting temperature can be achieved for specimens under investigations through this novel process thereby eliminating the need of using any filler powder. Absence of filler powder reduces the process cost significantly. The joints have been mechanically characterized by Vickers micro-hardness and physically characterized by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) tests. It has been observed through these tests that micro-hardness of the joints was more than the base alloy due to transfer of carbon from graphite rods to the joint zone. Page(s): 307-311 Wed, 01 Jun 2022 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/60071 2022-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/60070 Title: Investigation of micro-hardness of H11 die steel using composite material electrodes in EDM Authors: Goyal, Parveen; Kumar, Rajesh; Kumar, Sanjeev; Singh, Bharat Abstract: Electrical Discharge Machining (EDM), a non-traditional material removal process has been well recognized for its ability for precision machining of electrically conducting hard materials. Repetitive heating and cooling of the workpiece surface during the machining make the surface hard. During this process, the transfer of material into workpiece surface due to diffusion of material from the tool electrodes results in the desire surface modifications. This paper investigates the effect of electric discharge machining on H11 die-steel materials with composite material electrodes fabricated by stir casting as well as powder metallurgy process. Copper (85% by weight) has been used as matrix material with tungsten and carbon nanotubes (10%-5% by weight). The performance of fabricated composite electrodes has also been compared with conventional copper electrode. Microhardness achieved has been found to be best when H11 die-steel surface is machined with composite electrodes fabricated by powder metallurgy process. Also, the microhardness has been enhanced by 19.57% with optimal input parameters. Results show that optimum microhardness has been observed at high peak current value when surface is machined with copper conventional electrode while pulse on time has been found to the major contributor when surface is machined by composite material electrode. XRD analysis indicates the formation of tungstencarbide, iron-carbide, chromium- nickel and copper on the machined surface of the workpiece. Page(s): 312-322 Wed, 01 Jun 2022 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/60070 2022-06-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/60069 Title: Evaluation of wind pressure on the low-rise buildings and surrounding terrain under the influence of tornadolike vortex induced aerodynamic loads Authors: Moizuddin, Mohammed; Goyal, Rajesh; Gupta, Nakul; Matsui, Masahiro Abstract: Wind loading on buildings caused by straight line boundary layer winds has been thoroughly investigated in the past. The effects of vortex loading on structural projections will induce crosswind loads and torsional loads on low rise building which has severe dynamic resonant effect not only on the structural projections but also on over all structural elements of a building. These structural projections can be in the form of cantilever balconies, canopies, sunshades, overhangs, aesthetically projected elements. The purpose of each of these projections is different and designed to suit the convenience of habitats. During the tornado, the damage of projections becomes flying debris due to the fatigue effect of fluctuating pressure. In the present study,a model of low-rise buildings is tested under the influence of tornado-induced vortexes. Models were tested for F3 – F4 tornado for the wind speed 60m/s to 90m/s. Tornadoes of vortex core diameter 0.46 m to 1.06 m in a smooth open terrain, simulations were carried out.A prototype of model of building in a scale of 1:400, actual dimensions of building is 20m x 20m x 10 m; the prototype model is prepared using flexi glass. An arrangement is made to study the effect of building on the ground terrain in surrounding region of building. Model was provided with pressure tapping to measure the surface pressure on all the walls and roof. Page(s): 323-330 Wed, 01 Jun 2022 00:00:00 GMT http://nopr.niscpr.res.in/handle/123456789/60069 2022-06-01T00:00:00Z