Papers by Author: Da Peng Dong

Abstract: This paper investigates the surface integrity of premium thread gauge material 9Mn2V in reciprocating surface grinding using SG abrasive, which includes metallographic structure for grinding crack, specific grinding energy and surface residual stress. The specific grinding energy and the surface residual stress can be reduced after the workpiece gets tempered, so small grinding depth can lead to the generation of cracks when the workpiece is not tempered. Otherwise, the depth of heat affected zone increases with the increase of grinding depth, but not increases proportionally. After 9Mn2V is tempered, the occurrence of grinding burn and grinding cracks can be improved.

Abstract: This paper investigates the surface condition of 9Mn2V in conventional surface grinding using SG abrasive under different tempering processes, which includes metallographic structure, micro-hardness, specific grinding energy, surface roughness, surface morphology and surface residual stress. The experimental results indicated that the specific grinding energy increased after the completion of tempering. The ground surface quality improved evidently with the times of tempering increasing. Meanwhile the ground surface was in a state of high tensile residual stress after quenching. After the second time of tempering, the residual stress had significantly been reduced.

Abstract: Drilling procedure is widely used in orthopedic surgery to insert the steel nail to stabilize the bone. However, successful execution of bone drilling requires a high level of dexterity and experience, because the drilling resistance is large and sometimes vibrates violently to even break the slender drill. This paper introduces the study of drill force in different cutting parameters and different bone density. The density of cortical bone is higher than that of cancellous bone, so the drilling force decreases suddenly from the peak and then maintains a stable value. Drilling forces are more related with feed speeds and bone density. Drilling force increases as feed speed increases and bone density increases. Accurate drilling process can be obtained to provide effective surgery training and rehearsal.

Abstract: In recent years, with the development of machinery industry, micro-cutting technologies have been gradually moving into engineering realization. The paper carries out a series of works on simulation modeling of micro-cutting of Ti-5Al-5V-5Mo-3Cr considering tool edge radius. Unlike conventional cutting, in micro-cutting the effect of tool edge radius which has a marked impact on cutting force, specific cutting energy, burr formation and burr size can no longer be neglected.