高速切削淬硬钢已加工表面白层形成规律研究

摘要

High speed dry hard cutting process causes white layer on machined surfaces. Studying machined surface white layer is significant to improve work-piece machinability and performance. The experiments of high speed dry hard cutting of GCr15 steel and 40CrNiMoA steel were carried out with PCBN cutters,and the formation mechanism of the white layer on dry-hard machined surface were analyzed. The effects of cutting pa-rameters and carbon content in bulk material on white layer thickness were studied. The results show that mar-tensitic phase transformation is occurred during the formation process of the white layer. The white layer thick-ness is increased with increasing cutting speed,and then decreased with the increase of cutting speed. The white layer thickness is increased with the increase of flank wear and carbon content in the bulk material.%高速切削淬硬钢已加工表面存在白层,对工件使用性能具有很大的影响,研究已加工表面白层对改善工件表面质量和切削加工性具有重要意义.通过使用PCBN刀具高速干硬切削GCr15钢和40CrNiMoA钢实验,分析了高速干硬切削表面产生白层的机制,研究了切削速度、后刀面磨损量等切削参数以及材料含碳量对白层厚度的影响规律.研究表明:白层形成过程中,已加工表面材料发生相变,白层厚度随切削速度提高呈现先增加后减小趋势,随刀具磨损量增加而增大;随着工件材料含碳量增加,白层厚度增大.