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。     

硬车技术应用浅谈

对硬车技术使用进行分析,选用PCBN刀具作为的切削刀具。研究了PCBN刀具在冷轧工作辊切削加工中的应用,通过使用对比对刀具牌号、几何形状和切削参数的进行合理选择。     

切削不同铸铁材料的PCBN超硬材料刀具磨损研究现状

基于聚晶立方氮化硼(PCBN)超硬材料刀具的高硬度、良好的耐磨性及化学稳定性,其在汽车制造领域的应用变得越来越广泛。对国内外学者们使用PCBN超硬材料刀具加工灰铸铁、球墨铸铁和蠕墨铸铁的研究现状进行总结分析,主要从刀具材料、工艺参数、工件材料、切削环境及加工方式等几个方面对PCBN超硬材料刀具切削加工3种铸铁时的磨损机制进行讨论,最后总结了切削不同种类铸铁材料时刀具的磨损情况。     

PCBN刀具在切削含硼高速钢轧辊中的应用

分析含硼高速钢轧辊的加工性能,选用PCBN刀具作为切削刀具,通过加工过程的分析得出合理的切削参数。     

立方氮化硼超硬刀具材料的合成与性能研究

以CBN微粉、WC粉和Co粉为原料，在六面顶压机上合成PCBN复合片。研究了立方氮化硼超硬刀具材料（PCBN复合片）的合成规律，对PCBN复合片的微观结构和性能进行了分析。研究发现，当烧结温度为1 750℃时，WC/Co结合剂对CBN颗粒的结合力增强，此时样品的磨耗比最大，为7 750。将1 750℃烧结出的PCBN复合片做成刀具，连续切削球墨铸铁，切削里程为20 km时，PCBN刀具后刀面磨损量（VB）最小，为0.272 mm。随着温度升高，样品中的颜色偏差越来越少，厚度分布越来越均匀，平整度逐渐变好，说明提高烧结温度有助于提高复合片中CBN聚晶层的平整度。     

铸铁切削用PCBN刀具材料的合成与性能研究

以CBN,Al,Co为实验原料，经高温真空处理后，在六面顶压机上合成了铸铁切削用PCBN（聚晶立方氮化硼）刀具材料，研究了PCBN结合剂中Al-Co的质量配比对PCBN刀具材料的合成及相关性能的影响规律，以期得到性能优良的PCBN刀具材料。通过对PCBN的物相组成、显微硬度、致密度、微观形貌以及切削性能的分析，发现当Al-Co含量为8%时，样品的硬度与磨耗比最高，分别为35.72 GPa和7 560，当Al-Co含量10%时，获得相对密度和机械强度最好的PCBN刀具材料，分别为99.2%和882.5 MPa，当Al-Co含量为8%和6%时样品的切削性能相对较好。综合分析，当Al-Co含量为8%时可获得综合性能最佳的PCBN刀具材料。     

高速钢轧辊粗加工研究与分析

针对高速钢轧辊粗加工难度大、效率低下等问题,从高速钢轧辊的特点、机床性能、刀具材质、形状等方面进行分析,以PCBN圆刀具切削实物为研究对象,通过不同的工艺参数进行实验对比,验证刀具磨损的机理,选出合理的切削参数,达到提高加工效率的目的。     

硬质合金涂层刀具研究的新进展

随着现代机械加工工业朝着高精度、高速切削、干式切削技术以及降低成本等方向发展,人们对硬质合金刀具提出了更高的要求。涂层硬质合金具有高硬度和优良的耐磨性,延长了刀具的寿命,这是切削刀具发展的又一次革命。本文综述了目前国内外硬质合金涂层刀具在涂层方法、涂层种类和涂层基体等方面的新进展。     

铝合金高速加工的研究

简要介绍了高速加工的概念、内容和发展现状,分析了其切削参数,并着重介绍了高速切削的特点、高速加工对机床的要求及其在铝合金工件加工中的应用。     

高速镗削过程温度场的理论计算

分析金属在高速镗削状态下切削的温度模型及其在切削时主要热量产出的区域和传导方式,建立高速镗削温度场的热传导模型,并给定边界条件,将剪切和刀具/切屑摩擦产生的温度场求解问题转化为连续作用的移动线热源在孔内无限大表面移动的温度场求解问题。选用热源法计算刀具与工件发生剪切、刀具与切屑发生摩擦产生的热源在空间产生的温度,并进一步分析计算高速镗削中分布在刀具和切屑的温度。     

Synthesis of the nanodimensional powder of tungsten carbide for the development of functional nanocomposite coatings

Nanometric tungsten carbide for the formation of functional nanocomposite materials promising for making cutting tools and anodic electrodes is obtained by the methods of mechanosynthesis and mechanical activation. The structure formation of nanometric tungsten carbide is investigated and the interaction regularities in the metal-nonmetal system are investigated.     

高速切削铝合金用硬质合金刀具磨损机理研究

在高速切削加工铝合金涡轮过程中,硬质合金刀具的磨损会直接影响刀具的使用寿命和加工精度,导致加工精度无法满足设计要求,在磨损严重时还会引起刀具和零件的损伤。本文以高效切削铝合金涡轮用硬质合金刀具为研究对象,通过四因素三水平正交试验对刀具磨损行为进行研究,观测和分析不同切削参数下硬质合金刀具的磨损状态及微观形貌,讨论并提出有效控制刀具磨损的措施。结果表明,该控制刀具磨损的措施在保证零件加工精度的同时具有一定的实际推广价值。     

Al-TiC0.47-B系结合剂对合成聚晶立方氮化硼的影响

研究了Al-TiC0.47-B系结合剂掺杂合成的PCBN的抗压强度、磨耗比、连续切削性能与结合剂的掺杂量,Al,Tic0.47各自在结合剂中的含量及合成温度诸因素的关系。然后采用X射线衍射分析和扫描电镜分析技术对合成的PCBN试样的组织结构进行了分析，揭示了PCBN粘结相的相组成与相分布。     

Properties of a Tool Produced by Powder Metallurgy

To minimize the manufacturing costs of parts with specified operational properties, the machining processes must be optimized. Cutting accounts for at least 70% of such processes. To that end, tool materials with distinctive properties may be developed and utilized. Analysis of manufacturing components—in particular, power components in gas-turbine engines—shows the need for higher quality of the machined surfaces and more efficient use of expensive equipment with numerical and adaptive control systems, so as to ensure a wide range of cutting conditions, including high-speed cutting. To obtain products that are domestically and internationally competitive, we need to optimize cutting processes, in which the tool is the weakest link in the technological chain. Defects of the cutting tool impair the productivity and product quality. In the present work, the wear of cutting tools produced by the sintering of high-speed steel powder is studied. Tool materials based on high-speed steel with additional alloying by titanium carbide (carbide steel) are shown to be highly wear-resistant. They may be classified as a new category of self-organizing tool materials. The results indicate the expediency of additional alloying by two methods to modify the tool friction and wear: (1) alloying with compounds that considerably reduce the self-organization by decreasing the frictional coefficient at working temperatures; (2) alloying to expand the range of self-organization. Both methods result in lower frictional forces and temperatures, as confirmed by the change in wear resistance and frictional characteristics. The wear resistance of such tools is found to be 2–3.5 times that of regular high-speed steel tools.     

奥地利Plansee公司Tizit硬质合金的生产

Tizit硬质合金目前的生产,估计切削工具和可转位刀片占2/3,其余大部分是耐磨零件、成型工具和特殊零件。其中按重量计算碳化钛合金表壳占5%。生产涂层硬质合金及涂层高速钢,是该厂的一个特点。     

Development of Cutting Tool Through Superplastic Boronizing of Duplex Stainless Steel

In this study, a cutting tool is developed from duplex stainless steel (DSS) using the superplastic boronizing technique. The feasibility of the development process is studied, and the cutting performances of the cutting tool are evaluated and compared with commercially available carbide and high-speed steel (HSS) tools. The superplastically boronized (SPB) cutting tool yielded a dense boronized layer of 50.5 µm with a surface hardness of 3956 HV. A coefficient of friction value of 0.62 is obtained, which is lower than 1.02 and 0.8 of the carbide and HSS tools. When tested on an aluminum 6061 surface under dry condition, the SPB cutting tool is also able to produce turning finishing below 0.4 µm, beyond the travel distance of 3000 m, which is comparable to the carbide tool, but produces much better results than HSS tool. Through superplastic boronizing of DSS, it is possible to produce a high-quality metal-based cutting tool that is comparable to the conventional carbide tool.     

硬质合金基体对涂层刀具高速切削镍基高温合金切削性能的影响

采用热常数仪和高温维氏硬度计对Co含量(质量分数)分别为6%和10%的硬质合金进行热学性能与高温力学性能检测,然后用以这2种硬质合金为基体的涂层刀片对镍基高温合金GH4133进行高速车削,采用扫描电镜(SEM)和能谱(EDS)对车削后刀片的磨损区域进行观察和成分分析,研究刀片基体的Co含量对刀具切削性能的影响。研究结果表明,硬质合金中的Co含量由10%降低到6%时,热导率由62.78(W.m)/K升高到84.57(W.m)/K,与此同时同一温度下的高温维氏硬度提高10%左右;YBG202刀片(基体中Co含量为10%)的切削刃与后刀面的磨损均较迅速,而YBG102(基体中的Co含量为6%)刀片后刀面的磨损相对均匀,磨损速率低;基体中的Co含量由10%降低到6%时,刀片的切削寿命提高约3倍。故高速连续切削镍基高温合金时应当尽量选用低Co硬质合金作为刀片的基体。