PCBN刀具切削轴承钢时切削速度的研究

通过对PCBN刀具切削GCr15轴承钢时切屑形态、切削力、切削温度和表面粗糙度的试验研究,得到了切削速度对上述各量的影响规律.结果表明,切削速度对切削温度、切削力和表面粗糙度的影响存在一个临界值,采用临界切削速度进行切削,有利于提高经济效益.     

PCBN刀具断续切削淬硬钢瞬态冲击力研究

基于正交试验设计方法,使用PCBN刀具进行干式断续车削淬硬钢Cr12Mo V试验,研究了不同切削参数与工件硬度对瞬态冲击力的影响。应用响应曲面法建立了瞬态冲击力的线性预测模型和指数预测模型。研究结果表明:断续切削方式下,工件硬度和切削速度对瞬态冲击力有显著影响;线性预测模型和指数预测模型均能准确地对瞬态冲击力进行预测。     

PCBN刀具高速切削抗氢钢HR-2的性能研究

采用不同CBN含量和晶粒结构的PCBN刀具,在不同切削速度下进行了HR-2抗氢钢的高速精密切削试验。通过对PCBN刀具前、后刀面的显微形貌特征进行观测,分析了刀具的失效磨损机理,研究了不同CBN含量及不同切削速度对刀具使用寿命的影响。对刀具磨损的测量结果表明,PCBN刀具高速切削HR-2时,CBN含量高的刀具显示出更长的使用寿命,且在130-200m/min区间为最佳切削速度区域。SEM和EDS分析结果表明,高速精密切削HR-2的磨损机理为氧化磨损、扩散磨损、粘结磨损,同时存在磨粒磨损以及引起的微崩刃现象。     

PCBN刀具在微凸桶形滚轮加工中的应用

通过精密微凸桶形滚轮的加工难点的分析,指出应用PCBN刀具实现"以车代磨"的可行性。通过制定合理的加工工艺、设计专用工装、选择合适的刀具及几何参数、优化切削参数,解决了微凸桶形滚轮精密加工的难题,实际加工结果表明,该工艺方案可行,具有一定的推广价值。     

PCBN端铣刀精铣淬火钢时刀具合理几何参数的选择

通过铣削试验研究了PCBN端铣刀精密铣削淬火钢时刀具几何参数的选择,根据刀具最大耐用度原则确定了合理的刀具几何参数,并结合铣削力试验结果从理论上探讨了刀具几何参数对其耐用度的影响机理。     

An Investigation of the Wear Mechanisms of Polycrystalline Cubic Boron Nitride (PCBN) Tools when End Milling Hardened Steels at Low/Medium Cutting Speeds

The commercial availability of PCBN tools has created the possibility for great improvements in the area of machining hardened steels. Roughing and finishing cuts can be carried out to achieve a surface finish as good as that obtained by grinding. Through this procedure, fabrication time can be greatly reduced and quality increased. This work presents a study of the wear of PCBN and cemented carbide tools when end milling hardened steels at low/medium cutting speeds. The experiments were carried out using a 12.0 mm diameter end milling tool with an indexable insert tipped with PCBN. Removal rate was 384 mm 3 min −1 . Carbide inserts were also tested under the same cutting conditions. The tests were carried out in the dry condition. Three different hardened steels were cut and the wear mechanism was investigated using a scanning electronic microscope (SEM). The minimal wear mechanism found was a combination of adhesion and abrasion. The wear occurred predominantly on the flank face, although some indications of crater wear were also detected. The amount of wear was significantly smaller for PCBN tools than for cemented carbide tools.     

PCBN刀具的硬态切削加工机理

从PCBN刀具的物理特性、靡损特性、锯齿形切屑的形成机理、切削力和金属软化效应、已加工表面质量等方面综述了PCBN刀具切削淬硬钢的适应性,着重从刀具磨损,已加工表面白层和残余应力的形成论证了PCBN刀具在淬硬钢切削加工中的可行性。     

汽车车窗密封条辊压辊轮的数控加工

通过分析汽车密封条辊压辊轮的加工特点 ,提出采用PCBN刀具以车带磨实现辊轮复杂型面数控加工的工艺方案 ,介绍了辊轮数控加工的程序编制及加工模拟     

PCBN刀具铣削45钢的磨损规律研究

通过利用PCBN端铣刀铣削45钢工件的试验,进行了关于铣削速度对PCBN刀具磨损影响的研究,根据试验结果给出了加工45钢的适宜铣削速度。     

PCBN刀具干切削淬硬轴承钢时磨损机理的研究

通过干切削淬硬GCr15轴承钢的PCBN刀具磨损试验 ,得出了后刀面刀具磨损曲线 ,结合扫描电镜对刀具的磨损形态进行了宏观和微观观察 ,研究了PCBN刀具的磨损特征及磨损机理 ,并对切屑形态与刀具磨损之间的关系进行了初步探讨