【作者】 李新龙；

【导师】 何宁；

【作者基本信息】 南京航空航天大学 ， 机械电子工程， 2004， 硕士

【摘要】 钛合金以其质轻而强度高等特点，广泛应用于航空工业，但其加工效率问题一直是工业制造技术中迫切需要解决的难题。本文基于“绿色加工”理念，以钛合金TC4的高速铣削为对象，进行了利用低温氮气和微量润滑剂替代传统浇注切削液作为切削介质的探索性研究。主要工作如下： 1．在综合分析现有低温冷风发生装置的原理和结构后，提出了采用半导体制冷器作为冷源的构想。设计了新型的半导体制冷低温冷风发生装置，进行了建模仿真和大量的制冷性能测试试验等工作。该装置制冷性能能满足试验需求。 2．在常温氮气油雾、低温氮气和低温氮气油雾介质下进行了钛合金高速铣削的铣削力试验研究，分析了铣削力随铣削长度的变化规律以及刀具磨损对铣削力的影响。发现低温氮气和低温氮气油雾相比常温氮气油雾能有效地降低铣削力，而低温氮气油雾的效用更加明显。从切削介质的润滑和冷却性能以及钛合金的物理机械性能出发解释了上述现象产生的原因。 3．在常温氮气油雾、低温氮气和低温氮气油雾介质下进行了钛合金高速铣削的刀具磨损试验研究，发现低温氮气油雾相比其它两种介质能大大降低刀具磨损，提高刀具寿命，对切屑粘刀现象也有一定程度上的抑制。比较分析了三种介质下刀具的磨损量及宏微观磨损形态，较为详尽地阐述了三种介质下刀具的磨损机理。更多还原

【Abstract】 Ti alloy with characteristics of high intensity and light mass is used widely in aero industries. However, the low efficiency of Ti alloy machining has been the problem hard and urgent to solve in aeroplane industries. Based on "green machining", pioneer researches on high speed milling of Ti alloy TC4 with minimal quantities of lubricant carried by cooled nitrogen instead of traditional cutting fluids were done in this paper. The main work was summarized as follows:1. After analyzing the principles and structures of present cryogenic machining equipments for cutting or grinding center, a new method of producing cooled gas by semiconductor refrigeration equipment was proposed; Then based on the works of mathematic evaluation, design and manufacturing of primary parts and experiments for refrigeration performance testing, a new cryogenic machining equipment for cutting or grinding center was developed successfully.2.Under the conditions of nitrogen-oil mixture, cooled nitrogen and cooled nitrogen-oil mixture, the milling force experiments on high speed milling of Ti alloy TC4 were contrastingly done. The variational rules of milling force under different milling media and the variational rules of milling force with miller wear were analyzed respectively.3.The miller wear experiments and Scan Electronic Microscope(SEM) were used to a-nalyze the wear mechanism of miller under the conditions of nitrogen-oil mixture, cooled nitrogen and cooled nitrogen-oil mixture. The results show that comparing with other two media, the cooled nitrogen-oil mixture can reduce the miller wear greatly, increase the tool life and restrain the chip adhesion.更多还原