【作者】 佟艳娇；

【导师】 张弘弢；

【作者基本信息】 大连理工大学 ， 机械制造及其自动化， 2006， 硕士

【摘要】 PCBN刀具具有硬度高、耐磨性好、热稳定性和化学稳定性好，导热性良好以及摩擦系数低等优点，在硬态加工铁系材料时具有无可比拟的优越性，正逐步取代磨削加工而成为一种新的精加工途径。但由于PCBN刀具的脆性较大，在加工中易出现破损现象，大大降低了加工可靠性，并且PCBN刀具本身成本较高，破损后会造成较大的经济损失。因此在加工之前一定要对PCBN刀具的刃口进行处理以提高其抗破损能力，最常用最有效的方法就是在刃口处磨出负倒棱，这样就可以大大提高PCBN刀具在加工使用中的效率和可靠性，但在生产实践中PCBN刀具负倒棱参数往往仅凭借对硬质合金刀具的经验来选择，没有专门针对PCBN刀具的理论指导，因此有必要对PCBN刀具负倒棱在加工中的作用进行深入的研究。 PCBN刀具应用在淬硬钢中的切削性能目前国内外已有了大量的研究，并且得出了很多有价值的实验结果和结论。但是对于铸铁加工领域的研究则相对较少，除了对高速切削和铣削灰铸铁有较为深入的研究探讨外，关于PCBN刀具对球墨铸铁、蠕墨铸铁等材料加工应用的研究却很少，而这两种材料近些年已经大量的应用于汽车、航空、机床等制造业中，因此如何经济有效的加工这样难加工材料成为迫切需要解决的问题。 本论文共分四章：第一章绪论部分总结回顾了PCBN刀具的特性及应用现状，简要介绍了硬态切削技术以及PCBN刀具加工铸铁的现状；论文第二章系统地研究了PCBN刀具在加工淬硬轴承钢时负倒棱参数对切削力、刀具寿命、刀具磨损形式、加工表面粗糙度以及所得切屑形态的影响，同时验证了PCBN刀具在加工淬硬钢时切削参数与切削力的变化关系，通过对试验数据的分析和处理，得到PCBN刀具在负倒棱参数为γ₀₁=—15°、b_γ1=0.2mm时，精加工淬硬钢可以获得最好的加工效果；第三章中通过两种高含量CBN的PCBN刀具（BN500和BN700）在加工球墨铸铁时切削性能的对比分析，得出PCBN刀具在加工球墨铸铁时的磨损形式、加工表面粗糙度及切削力的变化范围等结果，通过对比实验结果得出BN700 PCBN刀具更适合加工球墨铸铁；最后在第四章对上述试验中出现的PCBNF刀具破损现象做了分析和总结，并对PCBN刀具近几年来的新发展做了概括。更多还原

【Abstract】 The PCBN cutting tool, with many advantages such as good wear resistance, thermal and chemical stability, low friction factor and so on, has incomparable superiority when hard machining ferreous materials, instead of grinding, is becoming a new kind of finish machining way. However own to high friability, the PCBN tool is easy to be broken in cutting process, which reduce machining process reliability greatly, and result in large economic loss for its high cost. Therefore, the cutting edge of PCBN tool must be disposed to enhance breakage resistance before machining, and the most common and effective method is to grind chamfer on cutting edge. In this way, the efficiency and reliability can be improved greatly. However the chamfer parameters often were selected just refering to the experiences of cement carbide tool, having not the special instructional theory, hence, it is necessary to carry on in-depth investigation in the effect of PCBN tool.Both in home and abroad there was abundant research on cutting hardened steel with PCBN tool, and many valuable experimental results and conclusions were obtained , but the research on PCBN tool cutting cast iron was rather limited. Except for research and discuss on turning and milling gray cast iron under high cutting speed, only few studies about machining nodular cast iron and vermicular cast iron with PCBN tool were carried out, while the two materials are widely used in manufacturing, specially automobile, aviation and machine tool. Therefore how to cutting these hard-to-machine materials economically and effectively is becoming an urgent-to-solve problem.There are four chapters in this thesis. In the chapter of introduction, the characteristics and application of PCBN tool were summarized and reviewed, and hard cutting technology and the situation of PCBN tool applied to machining cast iron were concisely introduced. In the chapter two, the effect of chamfer parameter of PCBN tool on cutting force, tool life, surface roughness and chip form was systemically investigated, meanwhile the variety relations between cutting parameters and cutting forces were verified when the PCBN tool turning hardened steel. Through disposed and analysed the experimental data, it was concluded that the best machining effect can be gotten at the chamfer parameter of γ ₀₁=-15° ,b_γ1= 0.2mm when the PCBN tool finish machining hardened bearing steel. In the third chapter of the thesis, the performances of the two high content CBN tool （BN500 and BN700） in machining nodular cast iron were compared and analysed, and the results about the wear更多还原