【作者】 杨钒；

【导师】 黄建龙；

【作者基本信息】 兰州理工大学 ， 机械制造及其自动化， 2013， 博士

【摘要】 绿色切削技术是现代制造业的主要发展趋势之一,而绿色切削过程中刀具的切削和摩擦磨损特性是其中一个十分重要的研究领域。本课题以过热水蒸汽作冷却润滑介质(OWVCL)和干式切削时不同增韧方式的A1203基陶瓷刀具的切削和摩擦磨损特性为主要研究目标,应用摩擦学、陶瓷材料学及金属切削加工学等理论方法,采用解析计算、试验研究以及计算机仿真等多种手段,研究A1203基陶瓷刀具在不同冷却润滑条件下切削难加工材料时的切削性能和摩擦磨损特性；不同冷却润滑条件、不同增韧方式对刀具材料摩擦磨损特性的影响,分析其磨损机理；并研究切削过程中与摩擦现象密切相关的加工硬化行为等,为A1203基陶瓷刀具在绿色切削中的应用提供理论依据和技术支撑。从热震试验、理论计算及有限元仿真分析等三方面综合考察TiC颗粒增韧、SiC晶须增韧、ZrO2相变增韧及纯A1203等四种A1203基陶瓷刀具材料的抗热震性能,为分析金属切削过程中热应力对上述刀具磨损行为的影响提供理论及试验依据。研究表明在三种增韧方式中,Zr02相变增韧对提高A1203基陶瓷材料的抗热震性能最有效,TiC颗粒增韧则较差,三种增韧A1203基复相陶瓷的抗热震性能都明显优于纯A1203陶瓷。通过微动摩擦试验研究了水蒸汽润滑及干摩擦条件下A1203基陶瓷刀具材料的摩擦磨损行为,为研究其在切削过程中的摩擦磨损提供了依据。研究表明水蒸汽润滑能有效降低A1203基陶瓷刀具材料的摩擦系数,减小磨损量。在合理范围内将车削过程进行适当简化,建立了过热水蒸汽冷却润滑和干切削时的斜角车削刀-屑接触面热力耦合模型,为分析不同冷却润滑条件下陶瓷刀具的摩擦磨损提供了参考依据。使用综合性能较好的Al2O3-TiC复相陶瓷刀具,研究其在过热水蒸汽冷却润滑(OWVCL)和干切削条件下连续切削高锰钢ZGMnl3及高强度钢AISI4340的性能。研究表明过热水蒸汽作为冷却润滑介质能有效地减小切削力,降低切削温度,并具有较好的加工表面质量。研究了三种A1203基复相陶瓷刀具在过热水蒸汽冷却润滑(OWVCL)和干切削条件下连续切削高锰钢ZGMnl3时的摩擦磨损行为。表明过热水蒸汽冷却润滑(OWVCL)能有效地提高Al2O3-SiC和Al2O3-TiC两种复相陶瓷刀具的耐磨损性能,但却会劣化Al2O3-ZrO2陶瓷刀具的耐磨损性能。研究在过热水蒸汽冷却润滑(OWVCL)和干切削条件下高锰钢ZGMnl3及304不锈钢的加工硬化行为,并做304不锈钢拉伸硬化试验进行对比,分析影响奥氏体钢在切削过程中加工硬化行为的主要因素,以期为在过热水蒸汽冷却润滑(OWVCL)条件下切削奥氏体钢的推广应用提供更好的依据。研究结果表明过热水蒸汽冷却润滑(OWVCL)能减轻奥氏体钢在切削过程中的加工硬化程度,同等切削条件下304不锈钢的硬化程度要小于高锰钢ZGMnl3,应变诱发的马氏体的量也远小于后者。更多还原

【Abstract】 Green cutting technology is a developing trend of modern manufacturing industry; both the cutting performance and tribological behavior of tool material are the most important research fields on green cutting technology. This dissertation focuses on the cutting performance and tribological behavior of Al2O3-base composites ceramics tool with overheated water vapor as coolant and lubricant cutting (OWVCL) and dry cutting as compared one. Using tribology, materials science and metal cutting theory, adopting analytical calculation, experimental study, computer simulation and other methods, under different cooling and lubricating conditions, the effects of tribological behavior of the tested ceramics tool materials with different toughening mechanisms, their wear mechanisms, and the work hardening in cutting process are all studied. The above researches to Al2O3-base composites provide theoretical and practical support for the application of Al2O3-base ceramics tools in green cutting.This paper presents three ways, thermal shock testing, theoretical calculation and finite element analysis to estimate the thermal shock resistance of four kinds of Al2O3-base composites ceramics tool, which provides the experimental and theoretical foundation for the wear behaviors of cutting tools with thermal stress on the cutting process. It was found that, by means of phase transformation-toughening, ZrO2adding can effectively improve the thermal shock performance of Al2O3-base ceramics, but the particle toughening one has a poor effect. And the thermal shock performances of three kinds of Al2O3-base composites ceramics were clearly better than that of the single-phase Al2O3ceramics.Using OWVCL technology, the results of fretting wear experiments of Al2O3-base composites ceramics show that the friction coefficient and wear of ceramics materials were all significantly reduced compared to dry friction, which provided the experimental and theoretical foundations to study the wear behaviors of the ceramics tools in cutting process.Adopting the analytic method, a friction model between tool and chip, based on appropriate simplification, was developed for the oblique cutting process under dry cutting and OWVCL technology, which provide the foundation for studying the tools wear behaviors on different coolant and lubricant conditions.composites ceramics was selected as the testing tools, which has good comprehensive properties; the cutting performance of Al2O3-TiC tools was studied in turning ZGMn13and AISI4340. The results showed that, compared to the dry cutting, reduction in the cutting force, surface roughness and cutting temperature were observed with OWVCL technology.With OWVCL technology, the results of wear experiments of the three kinds of Al2O3-base composites ceramics tools in cutting process show that the wear of Al2O3-TiC and Al2O3-SiC tools were markedly reduced, compared to dry cutting. On the contrary, wear of Al2O3-ZrO2tools was increased compared to dry cutting.The work hardening behaviors of ZGMnl3and AISI304in turning using Al2O3-TiC Ceramic tool were studied, compared to the tensile test of AISI304, the results showed that, with OWVCL technology, the work hardening extent was obviously decreased, compared to dry friction. Under the same condition, the work hardening extent of AISI304was considerably lower than ZGMn13, and the quantity of strain-induced martensite of the former is considerably less than the one of the latter, too.更多还原