Faculty Publications
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Item Investigation of Tribological and Corrosion Behavior of Cu-Ti Alloy Processed by Multiaxial Cryoforging(Springer, 2020) Ramesh, S.; Shivananda Nayaka, H.Wear and corrosion properties of Cu-3%Ti alloy subjected to multiaxial forging (MAF) under cryogenic conditions are estimated at room temperature. Wear study was performed using pin-on-disk dry sliding wear setup at 10 and 20 N loads with varying sliding distances (500-3000 m) under different sliding velocities (1 and 2 m/s). Coefficient of friction and wear mass loss decreases with an increase in MAF cycles, due to increases in hardness of samples. Wear resistance decreases with an increase in load and sliding velocity. Worn surface shows the plastic deformation regions, wear track, micro-cracks, micro-plowing groove and scratches. Potentiodynamic polarization test clearly shows that current density (Icorr) increases with an increase in MAF passes, because of grain refinement. Reduction in corrosion rate was evident from electrochemical impedance spectroscopy results which show increased diameter of the capacitive arc. An enhancement of corrosion resistance was revealed at higher MAF passes. © 2020, ASM International.Item Effect of cryogenic grinding on fatigue life of additively manufactured maraging steel(MDPI AG, 2021) Balan, A.S.S.; Kannan, C.; Kumar, A.V.; Hariharan, H.; Pimenov, D.Y.; Giasin, K.; Nadolny, K.Additive manufacturing (AM) is replacing conventional manufacturing techniques due to its ability to manufacture complex structures with near?net shape and reduced material wastage. However, the poor surface integrity of the AM parts deteriorates the service life of the components. The AM parts should be subjected to post?processing treatment for improving surface integrity and fatigue life. In this research, maraging steel is printed using direct metal laser sintering (DMLS) process and the influence of grinding on the fatigue life of this additively manufactured material was investigated. For this purpose, the grinding experiments were performed under two different grinding environments such as dry and cryogenic conditions using a cubic boron nitride (CBN) grinding wheel. The results revealed that surface roughness could be reduced by about 87% under cryogenic condition over dry grinding. The fatigue tests carried out on the additive manufactured materials exposed a substantial increase of about 170% in their fatigue life when subjected to cryogenic grinding. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Item Numerical modelling and analytical comparison of delamination during cryogenic drilling of cfrp(MDPI, 2021) Balan, A.S.S.; Kannan, C.; Jain, K.; Chakraborty, S.; Joshi, S.; Rawat, K.; F Alsanie, W.F.; Thakur, V.K.Carbon-Fibre-Reinforced Polymers (CFRPs) have seen a steady rise in modern industrial applications due to their high strength-to-weight ratio and corrosion resistance. However, their potential is being hindered by delamination which is induced on them during machining operations. This has led to the adoption of new and innovative techniques like cryogenic-assisted machining which could potentially help reduce delamination. This study is aimed at investigating the effect of cryogenic conditions on achieving better hole quality with reduced delamination. In this paper, the numerical analysis of the drilling of CFRP composites is presented. Drilling tests were performed experimentally for validation purposes. The effects of cooling conditions and their subsequent effect on the thrust force and delamination were evaluated using ABAQUS/CAE. The numerical models and experimental results both demonstrated a significant reduction in the delamination factor in CFRP under cryogenic drilling conditions. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Item Investigation of Tribological Characteristics of Cu-Ti Alloys Processed by Multi-Axial Cryo-Forging(Springer, 2022) Ramesh, S.; Shivananda Nayaka, H.S.; Anne, G.; Arun, M.N.; Naik, G.M.Cu-XTi alloys (X = 1.5 and 4.5%) were subjected to multi-axial forging (MAF) under cryogenic condition up to three passes successfully. Characteristics of the MAF-processed alloys were analyzed using microstructural analysis, hardness and wear tests. Worn surface morphology and elemental analysis was performed by scanning electron microscopy. The hardness of samples increases with higher MAF passes due to strain hardening and grain refinement. Wear test was done for six various sliding distances (500, 1000, 1500, 2000, 2500 and 3000 m), two different loads (10 and 20 N), and two different velocities (1 and 2 m/s) using the pin-on-disk wear test rig. Wear loss of as-received samples is higher than MAF-pressed samples due to an increase in hardness, but wear loss increases as the load increases. Coefficient of friction is reduced with the increase in MAF pass, which is due to strain hardening effect. The worn surface exhibits the plastic deformation regions, delamination, plowing and formation of oxide layers, which was revealed by energy-dispersive X-ray spectroscopy analysis. Also, MAF-processed samples exhibited abrasive wear mechanism as a result of formation of oxygen layer as revealed in SEM micrographs. © 2022, ASM International.Item Experimental Investigation on Surface Integrity in Cryogenic Machining of Maraging Steel(Springer, 2025) Varghese, V.; Sharma, P.; Ramesh, M.R.; Dupadu, D.; Sunilkumar, S.The study investigated the effect of machining environments such as cryogenic, wet, and dry conditions on the surface integrity of machined surfaces during end milling of MDN 250 maraging steel. During the machining of maraging steel, cutting temperatures and strain rates increased, resulting in a loss of mechanical properties and surface integrity of the machined surface. Surface integrity was an important factor influencing the components’ functional performance and quality, just like dimensional accuracy. In this study, the machining parameters such as spindle speed, feed rate, and depth of cut were kept constant, and the cutting environment was varied between cryogenic, dry, and wet conditions respectively. Surface integrity metrics such as surface roughness, microstructure evolution, residual stress, and microhardness were analyzed using Talysurf, electron back-scattered diffraction, x-ray diffraction, and Vickers microhardness test respectively. The correlated results conceded that cryogenic machining improved surface integrity compared to dry and wet machining. It also demonstrated that cryogenic machining was a viable manufacturing substitute to traditional machining using cutting fluids. The average grain size of the machined surface of the maraging steel under cryogenic, wet, and dry conditions was found to be 20.56, 24.92, and 11.54 µm respectively. The surface roughness was also reduced by up to 50% under the cryogenic environment compared to the dry environment. The residual stress results showed that stresses were compressive under dry, wet, and cryogenic environments, and the highest compressive stress was reported under a cryogenic environment (? 355 MPa). © ASM International 2025.