绿色磨削加工技术研究现状及进展

传统的磨削加工大量采用磨削液浇注法降低加工区温度,磨削液的大量使用给环境和操作者健康带来了很大危害,而且增加了磨削液排放回收的成本.本文分析了绿色磨削加工技术,如干磨削技术、微量润滑、液氮冷却、低温气体冷却、高压射流冷却、内冷却和固体润滑冷却技术在机械制造中的应用及其技术特征.绿色磨削加工技术将逐渐取代传统的浇注供液方...     

微量油膜附水滴磨削液的研究

使用冷风、微量可自然降解油剂(植物油或酯油)和少量水，经复合喷雾形成的微量油膜附水滴磨削液替代传统磨削液，在数控平面磨床上与磨削液分别为微量水、微量油及乳化液、可溶液的磨削加工进行了对比试验。试验结果表明，微量油膜附水滴磨削液可以达到乳化液和可溶液同等及以上的磨削性能，具有良好的润滑和冷却效果，适用于磨削加工。     

硬脆材料的激光辅助磨削加工研究进展

硬脆材料具有良好的材料力学性能,广泛应用于众多工业领域。但由于其硬度高及脆性大,导致其在磨削加工过程中容易产生脆性断裂等缺陷。激光辅助磨削加工是解决硬脆材料加工中产生缺陷的一种有效加工方法,国内外学者对此开展了大量研究。现从激光辅助加工的作用、激光辅助磨削加工方法方面对国内外的研究现状进行综述,并对硬脆材料激光辅助磨削加工技术未来的发展趋势进行了展望。     

超高速磨削加工及其关键技术

超高速磨削加工技术是一项综合性的高新磨削加工技术，具有传统的磨削加工技术不可替代的诸多优点，拥有光明的市场前景。文中根据国内外最新的研究资料，对超高速磨削加工技术的机理、特点及关键技术，进行了较为详实的介绍和论述。     

磨削液性能评价试验方法研究

针对磨削液的使用性能，按四球试验法、攻丝扭矩模拟评定试验法、磨削加工试验法对三种磨削液进行了性能试验研究。结果表明，四球试验法的结果重复性较好，但该方法以滑动摩擦接触面的油膜强度来评价磨削液的性能，与磨削加工试验的结果有较大差别。攻丝扭矩模拟评定试验方法为真正的切削试验，与切削加工的相关性较强。磨削加工试验是最能体现磨削液性能的试验方法，因影响因素较多，需要建立完善的试验装置和试验方法。     

工程陶瓷先进加工技术的研究进展

综述了国内外工程陶瓷的激光和电火花加工技术最新研究成果,对超声波、等离子、磨料水射流、微波等特种加工技术、复合加工技术以及在传统磨削技术基础上发展起来的ELID磨削技术进行了评述,分析得出工程陶瓷先进加工技术发展的必然趋势是多种先进加工技术相复合的加工技术。     

工程陶瓷先进加工技术的研究进展

综述了国内外工程陶瓷的激光和电火花加工技术最新研究成果,对超声波、等离子、磨料水射流、微波等特种加工技术、复合加工技术以及在传统磨削技术基础上发展起来的ELID磨削技术进行了评述,分析得出工程陶瓷先进加工技术发展的必然趋势是多种先进加工技术相复合的加工技术。     

多功能数控超声加工机床设计

介绍了回转超声加工的原理,对多功能数控超声加工机床各组成部分的设计进行了详细的阐述,研制出的机床可以进行磨料冲击加工、超声磨削钻孔、超声铣削和超声雕刻四种超声加工试验,并在多功能机床上做了磨料冲击加工试验,以及超声磨削钻孔与非超声磨削钻孔加工的对比试验.     

金刚石砂轮加工石材的综合影响因素分析

提出了金刚石砂轮加工石材时的综合影响因素分为5大类共40多种输入因素,这些因素均会影响磨削结果。重点分析了在石材加工中影响金刚石砂轮磨损的主要因素和加工参数对切削力的影响,得出加工参数和金刚石砂轮的制作方式是影响金刚石砂轮磨损的主要原因,并通过大量的磨削试验得到钎焊金刚石砂轮磨削花岗岩时的宏观磨损量和微观破损状态。而加工参数对切削力的影响为：磨削速度vs的增加使金刚石砂轮切削力降低;进给速度vf和磨削深度ap的增大都会导致切削力增大,磨削深度对切削力的影响要比进给速度明显。     

SP202磨削液的研制及其摩擦学性能评价

以Mo—B防锈剂和B—N极压剂作主要成份制备了一种新型磨削液。经专用试验台架试验、攻丝扭矩测定和磨削生产验证确认：该磨削液能降低磨削力、提高磨削比、改善加工表面质量。试验同时证明：磨削液的PD／PB值对磨削工艺是一项重要的摩擦学参数。     

ENVIRONMENTALLY CONSCIOUS MACHINING AND GRINDING WITH CRYOGENIC COOLING

High production machining and grinding is becoming essential to enhance productivity and profitability. But such machining technique inherently increases the machining and grinding zone temperature, which in turn enhances tool wear rate and impairs the product quality. Historically cutting compounds and grinding fluids are applied to control such high temperature. Not only are such cutting fluids not very effective, but most importantly they are being perceived as a major source of pollution from the machining and grinding industry. The drastic cooling action of liquid nitrogen jets does provide desirable temperature control along with other technological benefits. Several research groups and a few organisations in different parts of the world are investigating the effects of cryogenic cooling on the machinability and grindability of different work materials using different approaches.     

ENVIRONMENTALLY CONSCIOUS MACHINING AND GRINDING WITH CRYOGENIC COOLING

High production machining and grinding is becoming essential to enhance productivity and profitability. But such machining technique inherently increases the machining and grinding zone temperature, which in turn enhances tool wear rate and impairs the product quality. Historically cutting compounds and grinding fluids are applied to control such high temperature. Not only are such cutting fluids not very effective, but most importantly they are being perceived as a major source of pollution from the machining and grinding industry. The drastic cooling action of liquid nitrogen jets does provide desirable temperature control along with other technological benefits. Several research groups and a few organisations in different parts of the world are investigating the effects of cryogenic cooling on the machinability and grindability of different work materials using different approaches.     

Ultrasonic assisted dry grinding of 42CrMo4

In recent years, many cooling lubricants are classified as health hazards, while their end-of-life treatment poses numerous ecological threats. Dry machining is a solution for greener production and also is a favorable process from an economical point of view. However, compared to other machining processes, conventional grinding has a low material removal rate and involves high specific energy. A major part of the specific energy in grinding is changed to heat that makes harmful effect on surface quality. Therefore, in conventional dry grinding, as there are no cutting fluids to transfer the heat from the contact zone, the temperature of workpiece surface and grinding wheel surface will be increased resulted to thermal damage and poor surface integrity, increasing of wheel wear and inefficient grinding compared to conventional grinding. To make a step forward to pure dry grinding and to eliminate the negative environmental impact of the cutting fluids, a new technique called ultrasonic assisted dry grinding has been used. The advantages of ultrasonic assisted grinding were proved mostly for the brittle material. Our investigations show the improvement on the surface roughness, considerable reduction of the normal grinding force, and thermal damage in case of using ultrasonic assisted dry grinding compared to conventional dry grinding for a soft material, 42CrMo4. A decrease of up to 60% of normal grinding forces has been achieved.     

Minimal quantity lubrication-MQL in grinding of Ti–6Al–4V titanium alloy

Titanium and its alloys are attractive materials due to their unique high strength–weight ratio that is maintained at elevated temperatures and their exceptional corrosion resistance. The major application of titanium has been in the aerospace industry. On the other hand, titanium and its alloys are notorious for their poor thermal properties and are classified as difficult-to-machine materials. The problems that arise during grinding of titanium alloys are attributed to the high specific energy and high grinding zone temperature. Significant progress has been made in dry and semidry machining recently, and minimal quantity lubrication (MQL) machining in particular has been accepted as a successful semidry application because of its environmentally friendly characteristics. A number of studies have shown that MQL machining can show satisfactory performance in practical machining operations. However, there has been few investigation of MQL grinding of special alloys like titanium alloys and the cutting fluids to be used in MQL grinding of these alloys. In this study, vegetable and synthetic esters oil are compared on the basis of the surface quality properties that would be suitable for MQL applications. The cutting performance of fluids is also evaluated using conventional wet (fluid) grinding of Ti–6Al–4V. As a result, synthetic ester oil is found to be optimal cutting fluids for MQL grinding of Ti–6Al–4V.     

圆柱滚子外圆精密加工技术综述

圆柱滚子外圆精密加工技术作为圆柱滚子制造流程的终加工手段,对保证圆柱滚子的形状精度、尺寸精度、表面质量及其一致性起到关键作用。目前,依据加工原理不同,圆柱滚子加工方法主要分为无心磨削和无心超精研的工业主流传统加工方法,以及定心往复超精研、电化学机械光整、磁流体研磨、双平面方式超精研抛等非传统加工方法。介绍了上述不同加工方法的基本加工原理和研究现状,在加工精度、表面质量、生产效率等方面讨论了各加工方法的优缺点;展望了圆柱滚子外圆精密加工技术未来的发展方向,包括超精密工件和设备、高效自动化生产、高柔性生产、微小型零件、复合工艺、智能装备等。     

Current Approaches in Design and Supply of Metalworking Fluids

Metalworking fluids play a significant role in machining operations and have a substantial impact on tool life, shop productivity, and the quality of the workpiece. The results presented in this article show the influence of the properties of the metalworking fluids and the supply system on the workpiece quality in cutting and grinding processes. Chemical, physical, and tribological aspects have an impact on the properties of the generated surface. For the assessment of cooling effectiveness, a special test rig for the investigation of the coolant supply system in a grinding process is presented. Another approach to investigate the effectiveness and efficiency of the cooling and lubrication system during grinding is to monitor the temperatures and forces by a wheel-based measurement using telemetric data transmission. A further important aspect of water-soluble metalworking fluids is the influence of microbial effects on working results in machining. Microbial degradation leads to drastic changes in the physical and chemical properties of the metalworking fluid during service life. Besides the demands on the efficiency and economy of cutting processes, their environmental friendliness becomes a crucial issue itself. Therefore, an example for a holistic view on the environmental impacts of machining processes and the application of metalworking fluids is given.     

电火花机械复合磨削技术的研究进展

电火花机械复合磨削集合了机械磨削和电火花加工两种加工工艺,能够提高加工效率和加工质量,广泛应用于导电难加工材料的加工。本文对电火花机械复合磨削机理和研究现状进行了系统阐述,在分析现有研究成果的基础上,针对大口径Si C反射镜非球面成形磨削中存在的加工效率低、砂轮磨损严重等问题,提出了将电火花机械复合磨削应用于大口径Si C反射镜非球面成形磨削加工的观点,以提高其成形加工效率。     

工程陶瓷的加工技术

主要介绍了国内外工程陶瓷材料特种加工技术如电火花加工、激光加工、高速往复磨削、复合磨削、振动钻孔、超声波微孔等6项加工技术，以及3项常规加工新技术的开发及应用近况。