【摘 要】
：
The ultrahigh strength 300M steel has been commonly used in the manufacture of air-craft landing gear and rotor shaft parts due to its excellent mechanical properties.Creep feed grind-ing is one of the essential operations during the whole component manuf
【机 构】
：
School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;State Key Labor
论文部分内容阅读
The ultrahigh strength 300M steel has been commonly used in the manufacture of air-craft landing gear and rotor shaft parts due to its excellent mechanical properties.Creep feed grind-ing is one of the essential operations during the whole component manufacturing processes.In this work,the feasibility of creep feed grinding of 300M steel by using the hard zirconium corundum wheel was theoretically and experimentally evaluated.A variety of responses including grinding forces,temperature fields,specific grinding energy,surface integrity and chip modes were carefully recorded.Besides,the mechanism of ground surface profile generation and the spatial frequency spectrum of the surface profile were tentatively analyzed.It was found that the wheel speed has a relative influence on the grinding forces and temperatures of which the work hardening effect dominates the material removal with lower wheel speed while the thermal softening becomes crucial as the wheel speed exceeds the critical value for the studied 300M steel.Furthermore,a scattered spatial frequency spectrum for the generated surface profile was noticed with lower wheel speed while the spectrum gathers towards the lower frequency values with higher amplitude as the wheel speed increases.The shearing chip and flowing chip dominates the main chip type,indicating the excellent abrasive sharpness during the grinding process.In general,the used zirconium corundum wheel presents feasibility for the creep feed grinding of 300M steel because of the high material removal rate,absence of surface burn,low wheel wear and higher compressive residual stresses.
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