【作者】 杨永雷；

【导师】 徐宏海；

【作者基本信息】 北方工业大学 ， 机械制造及其自动化， 2008， 硕士

【摘要】 本课题采用微机控制的刀具深冷处理装置对高速钢W9Mo3Cr4V、W6Mo5Cr4V2和W4Mo3Cr4VSi钻头进行深冷处理;根据刀具的使用条件,通过金属切削实验,比较了深冷处理刀具和未经深冷处理钻头的耐用度、硬度和粗糙度。研究了深冷处理前后钻头的磨损规律、后刀面磨损形貌、以及金相组织变化。研究结果表明,经过深冷处理,W9Mo3Cr4V钻头硬度增加量为0.4～1.5,W6Mo5Cr4V2钻头硬度增加量为1.4,W4Mo3Cr4VSi钻头硬度增加量为1.2～1.5;W6Mo5Cr4V2钻头表面粗糙度减少量为0.04～0.11,W4Mo3Cr4VSi钻头表面粗糙度减少量为0.2～0.6;在相同的切削工艺下,深冷处理后的钻头耐磨性增强,并绘制出了不同规格W9Mo3Cr4V、W6Mo5Cr4V2和W4Mo3Cr4VSi钻头的深冷处理前后的磨损曲线;通过对钻头后刀面磨损形貌的观察结果发现,深冷处理后的钻头后刀面磨损程度明显轻于未经深冷处理的;利用扫描电镜,观察了深冷处理前后钻头试样的金相组织变化,结果表明,深冷后的试样析出了大量碳化物颗粒。深冷处理可以改变刀具材料的微观组织结构,增强刀具材料的耐磨损性能;并在一定程度上提高刀具材料的硬度,降低刀具的表面粗糙度。深冷处理使部分残余奥氏体转变为马氏体,且析出了大量的碳化物颗粒。析出弥散分布细小碳化物颗粒能提高抗磨损能力,也使得高速钢的硬度有所增加,所以深冷处理能提高高速钢钻头的耐磨性,延长钻头的使用寿命。更多还原

【Abstract】 In this paper,HSS(high speed steels)drill W9Mo3Cr4V,W6Mo5Cr4V2 and W4Mo3Cr4VSi were treated in the ultra-low temperature equipment;wear resistance,hardness,roughness of the cryogenic treated and cryogenic untreated drills were compared in the same metal-cutting conditions.The wear resistance,flank morphology,as well as changes in the microstructure of drills were researched before and after cryogenic treatment.The results show that,after cryogenic treatment,W9Mo3Cr4V increased in the hardness of 0.4～1.5,W6Mo5Cr4V2 increased in the hardness of 1.4,W4Mo3Cr4VSi increased in the hardness of 1.2～1.5;surface roughness reduction of W6Mo5Cr4V2 was 0.04～0.11,surface roughness reduction of W4Mo3Cr4VSi was 0.2 to 0.6;in the same cutting process,after the cryogenic treatment the tool wear resistance increased,and to map out the different specifications of W9Mo3Cr4V,W6Mo5Cr4V2 and W4Mo3Cr4VSi;before and after the deep cold treatment,the wear curve through the right flank morphology was observed.The results show that after the cryogenic treatment,the flank wear was obviously lighter than the untreated tools.By the use of scanning electron microscope,the author observed the changes in the microstructure before and after the deep cold treatment,the results showed that the cryogenic sample precipitated a large number of carbide Particles.Cryogenic treatment can change the micro-structure of tool material,enhance wearresistant of the tool materials,to a certain extent,improve the tool material’s hardness,and reduce the surface roughness.Cryogenic treatment made a part of residual austenite become martensite,and precipitated a large number of carbide particles,the diffusion of small carbide precipitation particles can increase wear-resistant ability,but also increase the hardness of high-speed steel,so cryogenic treatment can improve the wear resistance of high-speed steel drill bit,and extend the life of the tool.更多还原