Ashish Bhattacharyya - Academia.edu (original) (raw)
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Papers by Ashish Bhattacharyya
Wear, 2011
The dry sliding wear behaviour of a medium carbon steel against an alumina disk was studied in di... more The dry sliding wear behaviour of a medium carbon steel against an alumina disk was studied in different heat treated conditions. The wear mechanism in the hardened and tempered steel at 30 N and 40 N loads involved an initial adhesive wear followed by an intermediate oxidative wear regime and reappearance of the adhesive wear regime on removal of oxide layer. At 45 N load, the mechanism changed to abrasive wear along with the existence of intermediate oxidative wear of shorter duration. On the other hand, at lower (30 N) and higher (45 N) normal loads the wear mechanism in forced air cooled steel consisted of alternate regimes of adhesive wear and oxidative wear. However at 40 N load, the wear mechanism involved an initial oxidative wear regime for a long duration followed by an adhesive wear regime. The hardened and tempered steel with higher initial hardness and strength, exhibited better wear resistance at lower normal loads (30 N and 40 N) than the forced air cooled steel. However, its wear resistance at higher load (45 N) became inferior to the forced air cooled steel due to lesser extent of work hardening, shorter duration of oxidative wear regime and the abrasive wear being operative.
steel research international, 2011
In this research work the early fatigue damage characteristics up to 50% of life has been investi... more In this research work the early fatigue damage characteristics up to 50% of life has been investigated at near-endurance stress amplitude in a medium carbon steel with hardened & tempered and normalized conditions by application of post fatigue tensile loading. During fatigue loading microvoids were generated at the interphase-interface through vacancy clustering. Directional localized coalescence of these microvoids generated 'void sheets' in the normalized steel and 'craters' in the hardened & tempered steel. These defects acted as the potential sites for failure during post fatigue tensile loading deteriorating the mechanical properties. This was, therefore, clearly indicated that when a high tensile load is superimposed on near-endurance fatigue loading, material may fail much earlier than its actual fatigue life. The normalized steel suffered from more reduction in ductility than the hardened & tempered steel indicating more susceptibility to fatigue damage.
Wear, 2011
The dry sliding wear behaviour of a medium carbon steel against an alumina disk was studied in di... more The dry sliding wear behaviour of a medium carbon steel against an alumina disk was studied in different heat treated conditions. The wear mechanism in the hardened and tempered steel at 30 N and 40 N loads involved an initial adhesive wear followed by an intermediate oxidative wear regime and reappearance of the adhesive wear regime on removal of oxide layer. At 45 N load, the mechanism changed to abrasive wear along with the existence of intermediate oxidative wear of shorter duration. On the other hand, at lower (30 N) and higher (45 N) normal loads the wear mechanism in forced air cooled steel consisted of alternate regimes of adhesive wear and oxidative wear. However at 40 N load, the wear mechanism involved an initial oxidative wear regime for a long duration followed by an adhesive wear regime. The hardened and tempered steel with higher initial hardness and strength, exhibited better wear resistance at lower normal loads (30 N and 40 N) than the forced air cooled steel. However, its wear resistance at higher load (45 N) became inferior to the forced air cooled steel due to lesser extent of work hardening, shorter duration of oxidative wear regime and the abrasive wear being operative.
steel research international, 2011
In this research work the early fatigue damage characteristics up to 50% of life has been investi... more In this research work the early fatigue damage characteristics up to 50% of life has been investigated at near-endurance stress amplitude in a medium carbon steel with hardened & tempered and normalized conditions by application of post fatigue tensile loading. During fatigue loading microvoids were generated at the interphase-interface through vacancy clustering. Directional localized coalescence of these microvoids generated 'void sheets' in the normalized steel and 'craters' in the hardened & tempered steel. These defects acted as the potential sites for failure during post fatigue tensile loading deteriorating the mechanical properties. This was, therefore, clearly indicated that when a high tensile load is superimposed on near-endurance fatigue loading, material may fail much earlier than its actual fatigue life. The normalized steel suffered from more reduction in ductility than the hardened & tempered steel indicating more susceptibility to fatigue damage.