天然金钢石工具的解理破损

The cleavage fracture is the most common form of wearing and tearing in natural diamond tools. Through an analysis of the crystal structure, the reasons why the phenomenon of cleaving occurs in diamond are explained in detail and the position of a cleavage plane in an octahedron or a dodecahedron diamond and its criterion are given in terms of the concept of the covalent bond density per     

CBN砂轮修整方法及其对磨削表面完整性的影响

本文就树脂结合剂CBN砂轮的修整方法及其对磨削表面完整性的影响进行了研究。结果表明,目前常用的油石修整法等不能得到有效的修整和磨削结果,在磨削表面造成严重的热损伤,而本文提出的弹性修整法和超声波振动修整法修整效果显著,可以较准确地控制CBN磨粒的凸出高度,使砂轮具有很强的切削能力,获得高的生产率和磨削表面完整性。     

精密和超精密加工技术的新进展

精密和超精密加工技术的发展,直接影响尖端技术和国防工业的发展。世界各国都极为重视,投入很大力量进行开发研究,故近年来发展迅速。本文介绍了国内外精密和超精密加工技术各主要领域的最新进展:精密和超精密机床的新发展,超精密切削机理和金刚石刀具的研究,精密镜面磨削和研磨技术的新发展,非球曲面精加工技术的发展以及微型机械制造中的精微加工技术的发展;提出我国应重视精密加工的研究,加大投入,加速提高我国精密和超精密加工技术水平。     

黑色金属的超低温金刚石超精密切削

黑色金属的超精密切削问题一直是超精加工领域中未能解决的难题。本文提出了在超低温状态下用天然金刚石单晶车刀超精密切削黑色金属的新工艺,为解决这个难题开辟了新的途径。实验结果表明,在超低温状态下,金刚石车刀切钢时的急剧磨损可以有效地被抑制,刀具寿命增加,从而使黑色金属的金刚石超精密切削成为可能。     

钻削力测量的新方法

设计了一种应变片与压电晶体相结合的新型四向钻削测力仪,介绍了测量系统工作原理及对普通麻花钻钻削力及扭矩的测量实例。     

ELID镜面磨削砂轮氧化膜生成机理

采用铸铁结合剂微细超硬磨料砂轮进行在线电解修整磨削时,ＥＬＩＤ砂轮表面产生的氧化膜起着极其重要的作用。研究了ＥＬＩＤ砂轮电解氧化膜的粘附强度、硬度、致密性、导电性、生成速度与砂轮结合剂成分、磨削液成分和电解参数的关系。     

一种新的临界稳定公式及其绝对稳定切削判据

1. The transfer function of .chatter and its extend results. Experiments show that when chatter is excited, the dynamic cutting forces in cross directions are linearly related, i. e. Fc (S) = aFd (S). Here Fc (S) and Fd (S) are individualy the cross force and direct force, a is the linear factor. So the transfer function of the structure is Gd(S)+aGc(S), Gd(S) and Gc(S) are individually direct dynamic compliance and cross one. Therefore, the transfer fuction of the cutting chatter loop should be A system which can be calculated as a single degree of freedom has been designed by the authors for the test. Its damping ratio can be adjusted from 0.03 to 0.8. When chatter is just excited, μ = 0 and the natural damping ratio of the structure just offset by the cutting damping ratio. The results of measuring shows the latter ratio is-0.18. According to the for-mula (3), we can get critical cutting width 21.9mm, and the test value is 20.5mm. But the value of Tlusty formula is 26.97mm.The confirming test has proved the theory and the formulas in this paper are correct. They show that the absolutly stability criterion is not only related to the maxmum dynamic negative part of the real compliance of the structure but also to the maxmum negative coefficient of cutting damping force and the frequency of the chatter. The test show the formula (3) can be used for forecasting the cutting clatter.     

超硬刀具材料PCBN的发展及其应用

１引言聚晶立方氮化硼ＰＣＢＮ（ＰｏｌｙｃｒｙｓｔａｌｉｎｅＣｕｂｉｃＢｏｒｏｎＮｉｔｒｉｄｅ）是目前利用人工方法合成的硬度仅次于金刚石的新型刀具材料,由于它具有远远高于其它材料的硬度,因此它与金刚石统称为超硬刀具材料。１９５７年美国通用电气（ＧＥ）公...     

NURBS曲线插补技术的应用

高速ＣＡＤ／ＣＡＭ 技术的不断发展,促进了ＮＵＲＢＳ曲线插补技术应用于机械制造领域。针对以往应用直线插补存在的问题,对比介绍了ＮＵＲＢＳ插补的原理与实际应用的特点,并且论述了ＮＵＲＢＳ曲线插补相关的软硬件技术的发展动向。     

非球面模芯ELID磨削系统的研制

针对非球面模芯超精密磨削加工问题,研制了在线电解修锐(ELID)磨削系统。该系统应用平行法磨削原理,用整形后的球头砂轮进行非球面模芯的超精密磨削加工;利用非球面模芯工件本身的导电性能,以铸铁结合剂CBN砂轮作为阳极,以模芯本身作为阴极,通过ELID电源参数(电流、电压、占空比)的合理选择,解决了CBN球头砂轮的修锐,稳定地实现了小口径非球面模芯的ELID超精密磨削加工。