共查询到16条相似文献,搜索用时 390 毫秒
1.
2.
3.
4.
进行了PCBN刀具切削淬硬合金钢42CrMo的实验.通过JSM649OLV型扫描电子显微镜(SEM)观察PCBN刀具的磨损,利用INCA能量分散光谱仪(EDS)分析了刀具磨损面的金属元素成分,对刀具磨损的机理进行分析和探讨.通过对比几种切削速度下刀具的磨损量,获得切削速度的最佳值. 相似文献
5.
6.
7.
本文采用单因素试验法,研究PCBN刀具铣削灰铸铁HT200的切削速度对刀具耐用度的影响规律,给出了PCBN刀具铣削HT200的切削速度范围,主要分析了PCBN刀具铣削灰铸铁HT200的磨损规律。 相似文献
8.
使用聚晶立方氮化硼(PCBN)刀具车削V571材质粉末冶金气门座圈,研究负倒棱宽度对刀具磨损的影响规律。采用单因素试验法,在不同PCBN刀具负倒棱宽度下进行切削。结果表明,负倒棱宽度为0.10mm的PCBN刀具有更小的磨损和更长的刀具耐用度。 相似文献
9.
主要介绍了多晶CBN(PCBN)材料的发展现状和前景以及作为刀具材料的机械性能和切削性能,包括PCBN材料的硬度和横向断裂强度,以及在切削加工中的刀具磨损、切削力和加工工件表面粗糙度。研究发现,切削速度对PCBN刀具切削加工性能的影响较大,其次是刀尖钝圆半径。新型无结合剂PCBN刀具材料的切削性能优于含结合剂的普通PCBN,其切削过程受工艺参数影响较小,刀具磨损和切削力也相对较小,从而能够得到精度更高的加工表面。此外,对PCBN刀具在黑色金属超精密加工中的已有研究结果及发展方向进行了分析。 相似文献
10.
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。 相似文献
11.
12.
13.
14.
Owing to heavy dynamic and thermal loads, PCBN tools are seriously worn during hard cutting, which largely constrains the improvement of their machining performance. Therein, the chamfered structure of a cutting edge has a notable influence on the tool wear. Thus, a comparative study was carried out on the wear morphology and wear mechanism of PCBN tools with either a variable chamfered edge or an invariable chamfered edge. The results indicate that, for a PCBN tool with a variable chamfered edge, the rake wear area is far from the cutting edge and slowly extends toward it. A shallow large-area crater wear occurs on the rake face, and the flank wear area has a long triangular shape with a smaller wear area and width, and the cutting edge remains in a good state during the cutting process. In contrast, for a PCBN tool with an invariable chamfered edge, a deep small-area crater appears on the rake face,and the wear area is close to the cutting edge and quickly extends toward it. Thus, it is easy for chips to accumulate in the crater, resulting in large-area and high-speed wear on the flank face. In addition, the tool shows a weak wear resistance. In the initial wear stage, the rake wear mechanism of the two cutting tools is a mixture of abrasive, oxidation, and other types of wear, whereas their flank wear mechanism is dominated by abrasive wear. With an aggravation of the tool wear, the oxidation and di usion wear mechanism are both increasingly strengthened. The rake wear of the cutter with a variable chamfered edge showed an obvious increase in the oxidation and di usion wear, as did the flank wear of the cutter with an invariable chamfered edge. This study revealed the wear mechanism of the PCBN tool with a variable chamfered edge and provided theoretical and technological support for its popularization and application in the machining of high-hardness materials. 相似文献
15.
针对PCBN刀具在硬切削加工中磨损严重、切削寿命短的问题,开展了PCBN刀具深冷处理试验和经深冷处理的PCBN刀具高速硬车削AISI 4340钢的试验,研究深冷处理对PCBN刀具表面完整性(包括微观形貌、粗糙度、显微硬度和残余应力)及切削性能的影响规律,探究提高PCBN刀具耐磨性和刀具寿命的方法。研究结果表明,经过深冷处理之后,刀具表面缩松缩孔等缺陷明显减少甚至消失,表面形貌得到改善,但刀具表面粗糙度增大;刀具表面显微硬度、残余应力均得到提高;表面形貌和表面残余应力对刀具寿命影响较大,其次是表面显微硬度,表面粗糙度对刀具寿命影响较小。深冷处理后,刀具黏结、氧化磨损减少,刀具寿命较未处理刀具提高24.78%,可见,深冷处理可有效改善PCBN刀具表面完整性,从而提高刀具寿命。 相似文献
16.
基于激光加热辅助切削和超声椭圆振动切削提出了激光超声复合切削加工工艺。采用聚晶立方氮化硼(PCBN)刀具对YG10硬质合金进行了常规切削,超声椭圆振动切削,激光加热辅助切削和激光超声复合切削对比试验。检测了刀具磨损量、刀具磨损形貌、工件表面粗糙度以及工件表面形貌,并通过扫描电镜(SEM)对刀具磨损区域进行了能谱分析,同时研究了激光超声复合切削硬质合金时PCBN刀具的磨损及其对工件表面质量的影响。最后,与常规切削、超声振动切削及激光加热辅助切削进行了对比试验。结果表明:激光超声复合切削时刀具使用寿命显著增加,加工后的工件表面粗糙度平均值分别降低了79%、60%和64%,且工件表面更加平整光滑。激光超声复合切削硬质合金时,PCBN刀具的前刀面磨损表现为平滑且均匀的月牙洼磨损,后刀面磨损表现为较窄的三角形磨损带和较浅的凹坑和划痕;刀具的失效机理主要为黏接磨损、氧化磨损和磨粒磨损的综合作用。 相似文献