高速切削超高强度合金钢时次表面层组织特性研究

在切削速度范围157~314m/min内,在23-1析因设计的基础上,对兵器用难加工材料超高强度合金钢进行了高速干式铣削试验。在考查表面特征测量值———表面粗糙度变化规律的基础上,深入分析了加工表面层一定深度内微观金相组织变化规律与显微硬度变化规律。研究结果表明,高速切削超高强度合金钢时,切削用量对工件表面层组织特性有显著影响;高速加工过程对可见表面之下会产生塑性变形堆积层、回火马氏体、过度回火马氏体和回火索氏体等变化;当以较高的切削速度铣削超高强度合金钢时,选择较大的每齿进给量对工件表层金相组织造成的影响较小。

Study on the Metallurgical Structure Characters of Sub-surface Layer of Ultra-high Strength Alloy Steel in High Speed Milling Condition

With the cutting speed of 157314m/min, by use of 2~(3-1) factorial design, the high speed dry face-milling experiments were carried out on an ultra-high strength alloy steel, a type of difficult-to-cut materials used widely in ordnance industry. Beside the regularity of cutting parameter on surface roughness, the characters of metallurgical structure and microhardness distribution in work-piece's sub-surface layer were also discussed.It was concluded that, when high speed milling of this ultra-high strength alloy steel, the cutting parameter had remarkable effects on the metallurgical structure of sub-surface layers; the effects were plastic deformation, over tempered martensite, under tempered martensite etc.; larger feed per tooth in high speed milling process could bring unremarkable influence on the metallurgical structure of sub-surface layers.