PCBN刀具的发展性能及应用

从材料性能角度介绍PCBN刀具的特点及应用领域 ,并介绍最新的PCBN刀具多媒体数据库咨询管理系统     

PCBN刀具负倒棱前角的合理设计及其对表面残余应力的影响

本文研究了ＰＣＢＮ刀具负倒棱前角的合理选择，并用Ｘ射线衍射仪测量了加工表面残余应力，分析了负倒棱前角在形成表面残余压应力过程中的作用。     

PCBN刀具高速精密切削W-Ni-Fe合金的性能研究

采用PCBN刀具对W-Ni-Fe合金进行高速精密切削试验,通过观测PCBN刀具前、后刀面的磨损形貌,分析了刀具的失效磨损机理;从CBN含量、刀具参数以及已加工表面粗糙度方面研究了PCBN刀具加工W-Ni-Fe合金的切削性能。结果表明,CBN含量高且刀尖圆弧半径大的PCBN刀具具有更长的使用寿命,在高速、低进给、小切深条件下可获得良好的表面质量。SEM和EDS分析结果表明,PCBN刀具高速精密切削W-Ni-Fe合金的磨损机理为粘结磨损、扩散磨损、局部剥落、氧化磨损以及崩刃磨损等多重磨损机理共同作用的结果。     

Influence of grinding parameters on the quality of high content PCBN cutting inserts

Plunge-face grinding is commonly used to finish PCBN cutting inserts. In order to reach an adequate process design, an investigation of the influence of the grinding parameters on the quality of high content PCBN inserts is carried out in this work. For this, the inserts are ground with different grinding wheels (including a variation of grain size and bonding), dressing feed rates, feed and cutting speeds and the edge chipping and flank face roughness are measured. It was found that a reduction of the abrasive grain size as well as an increase of the dressing feed rate lead to an improvement of the insert edge and surface quality. Moreover, a variation of the cutting and feed speeds has only a small influence on the PCBN insert quality.     

整体PCBN刀具在高速重度断续切削端盖中的应用

对硬质合金刀具和整体PCBN刀具高速重度断续切削多回转阀门执行器用方形铸铁端盖时的刀面磨损和切削性能进行了对比试验。根据试验结果并结合目前高速重度断续切削加工中存在的问题,确定选择整体PCBN刀具作为重度断续高速切削方形铸铁端盖的切削工具。最终加工实例验证了整体PCBN刀片在提高刀具使用寿命和切削效率方面的优良特性。     

PCBN刀具异常损坏的原因分析

为了研究PCBN刀具异常损坏的原因，在CA6140普通机床上，使用自产和国外PCBN刀具，分别以三种不同装刀高度进行切削实验。结果表明：装刀高度偏离正常装刀位置，均会使PCBN刀具在使用过程中出现异常损坏。通过对三种装刀高度的刀具切削受力分析，指出：装刀高度过高或过低，都是PCBN刀具产生不同程度损坏原因。     

直径51mm PCBN刀具材料的开发研究

通过对合成工艺进行创新设计,运用新研发的相关配装物料,在六面顶压机上合成、开发出直径51mm刀具用PCBN复合片。扫描电镜组织形貌、超声波C扫描及切削试验等的性能检测表明,所开发的51mmPCBN复合片具有均匀致密的组织结构,表面无变形,PCBN层厚度处于0.85-1.0mm,边缘与中心均匀一致,具有良好的可加工性能,复合片边缘与中心加工成刀片的后刀面磨损量差值为13.88%。     

聚晶立方氮化硼刀具刃口放电加工工艺研究

通过调整电火花加工的主要放电参数（脉冲宽度和加工电流）,对聚晶立方氮化硼（PCBN）4~进行放电加工,进而对样刀刃口表面进行x射线衍射分析,并在扫描电子显微镜下观察其表层结构及能谱分析。通过对加工后样刀表面变质层主要成分及产生原因的分析,总结了脉冲宽度和加工电流对样刀表面变质层厚度、刃口表面粗糙度影响的关系曲线,为制定精密快速放电加工PCBN刀具的工艺提供了重要依据。     

PCBN刀具的磨损与最佳切削速度的研究

PCBN刀具磨损机理一直都被人们所关注,本文通过PCBN刀具切削淬硬合金钢42CrMo的实验,利用扫描电镜对切屑及刀具磨损进行能谱分析,找出PCBN刀具磨损与切削速度的关系。     

PCBN tool wear modes and mechanisms in finish hard turning

The use of polycrystalline cubic boron nitride (PCBN) cutting tools in hard turning applications is continuously growing with the number of commercially available grades increasing, allowing new application areas to be explored. In order to take full advantage of the benefits offered by PCBN it is necessary to understand the behaviour of the material in application. Tool behaviour is influenced by many factors which include the composition of the PCBN material, the steel workpiece, the nature of the cutting operation, the cutting conditions and the tool geometry.

The focus of this paper is the continuous turning of hardened steels. A significant amount of research has been carried out in this area and a literature review of the relevant work is presented. This identifies the primary wear modes and discusses the many theories proposed to explain the mechanisms contributing to PCBN tool wear and failure. The final section of the paper considers the critical factors that influence the behaviour of PCBN tools in continuous hard turning and how this knowledge can be applied to optimise tool performance.