摘要
为了深入探究涂层硬质合金刀具切削奥氏体不锈钢的切削机理,试验采用确定的进给量和背吃刀量,只改变切削速度的单因素法,来研究切削速度对奥氏体不锈钢工件加工表面质量的影响以及涂层刀具的切削机理。采用JEOL JSM-6360LV扫描电子显微镜和EDS能谱仪对工件加工表面及磨损刀片进行表面微区磨损形貌的观察分析与组成成分分析,采用X射线衍射仪对工件表面物相组成进行分析,采用激光扫描显微镜LSM对工件表面三维形貌进行观察分析。研究表明,切削速度较低时,不锈钢材料因材质较软,断屑性能较差;速度较高时,切削过程中粘着现象严重,致使摩擦剪应力较大,摩擦表面发生形变,进而诱发不锈钢的马氏体相变。因此,宜选用中速V=85m/min进行切削,在此速度下,被加工件获得的表面质量较好,表面粗糙度Ra=3.679μm。刀具磨损主要发生在前刀面靠近刀尖的部位,磨损机理主要表现为粘着磨损。研究发现,涂层硬质合金刀具在体现出一定的良好切削性能的同时也不可避免地发生了磨损,所以深入研究其切削机理能够丰富涂层刀具的切削理论,为提高涂层刀具在切削难加工材料时的刀具寿命以及拓展其在实际切削加工中的应用范围提供试验依据。
In order to further explore the wear mechanism of the coated carbide tools cutting austenitic stainless steel and to study the influence of cutting speed on the quality of machined surface,the tests were carried out by using single factor method in which only cutting speed was changing and the feed amount and cutting depth were fixed.The wear morphology of the machined surface was observed by JEOL JSM-6360 LV SEM,and the composition of the machined surface and the worn surface of cutting tools were analyzed by using EDS.X-ray diffraction and LSM were also employed to analyze phase composition and three-dimensional shape of the workpiece surface,respectively.The researche shows that,because of the material softness at lower speed,the chip breaking performance of the stainless steel is poor.At high speed,however,the serious adhesion phenomenon during the cutting process cause larger friction shearing stress so that the friction surface deformation would occur,leading to the martensitic transformation of stainless steel.Therefore,it is suitable to choose a middle speed（V=85m/min）to machine austenitic stainless steel.A better quality of machined surface has been obtained and the roughness of the surface is Ra=3.679μm.Tool wear occurs mainly at therake face close to the tool nose,the major wear mechanism is adhesive wear.It can thus be seen that,coated carbide tools embody certain good cutting performance,but the wear also inevitably take place.Therefore,the further study of tool＇s cutting mechanism can not only enrich the coated carbide tools cutting theory,but also provide experimental basis of improving the tool＇s life when cutting hard machining materials and extend the scope of its practical application.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2016年第3期437-444,共8页
Journal of Materials Science and Engineering
基金
国家自然科学基金资助项目(51405278)
陕西省教育厅专项科研计划资助项目(14JK1082)
陕西科技大学引进博士科研启动基金资助项目(BJ11-0)
