论文总字数：17562字

摘 要

Ti6Al6V合金是一种典型的难切削材料，材料本身的内应力与切削过程中不可避免的热量使切削区域温度上升明显，材料冷却硬化后在其表面生成的残余应力严重影响着最终加工成品的质量。然而，钛合金与其他常用合金相比，如钢铁、铝合金等，其优异的性能使得其极大地应用于了众多领域，例如耐热性高、耐腐蚀性强、比强度高等。因此，有效地提高钛合金材料零件的质量对工业发展具有重大意义。为了保证零件最终加工面呈现较优的残余应力分布，本文采用电磁感应加热技术来对Ti6Al4V合金进行预热处理以改善工件的表面质量，目的是提高材料表面硬度、耐磨性、疲劳强度以及减小材料最表层与次层次间的温度差，心部仍保持韧性状态，基于此法能更直观的观察切削后表面残余应力的变化趋势。

首先，根据所选Ti6Al4V合金的物理性能，了解钛合金在不同温度下各组织的状态，利用电磁感应加热技术制定出合适的工件表面预热优化处理工艺流程，合理控制缩小工件材料外表层与次表层间的温度差。

接着，利用ABAQUS有限元仿真软件进行模拟实验研究。选用了经典的二维正交切削模型，建立了四节点双线性热力耦合单元，通过线性递增改变工件表面外表层与次表层间的温度差，观察不同温度差下残余应力的走向趋势，最终发现当温度差值为100℃左右时，残余应力的分布最优。

关键词：钛合金 电磁感应 切削仿真 残余应力

Abstract

Ti6Al6V alloy is a typical difficult cutting material. The internal stress of the material itself and the inevitable heat in the cutting process make the temperature of the cutting area rise obviously. The residual stress generated on the surface of the material after cooling and hardening seriously affects the quality of the finished products. However, if titanium alloy is compared with steel and aluminum alloy, its performance will be better and its application field will be more extensive. What is common is that titanium alloy is more heat-resistant, corrosion-resistant and has higher specific strength. Therefore, it is of great significance to improve the quality of titanium alloy parts. In order to ultimately ensure parts processing surface rendering more optimal residual stress distribution, this paper USES the electromagnetic induction heating technology to preheat the Ti6Al4V alloy processing to make the material surface harder, more wear-resistant and more fatigue resistant, the difference in temperature between the core remains toughness condition, based on this method can be more intuitive to observe the change trend of surface residual stress after cutting.

First, according to the physical properties of the selected Ti6Al4V alloy, the microstructure of titanium alloy at different temperatures can be understood, and the appropriate surface preheating and optimal treatment process can be worked out by using electromagnetic induction heating technology. The optimal performance can be obtained after reaging after solution annealing.

Then, the ABAQUS simulation software is used for experiment. The classic two-dimensional orthogonal cutting model was used to establish a four-node bilinear thermodynamic coupling element. Gradually increase the temperature difference between the surface layer and the sub surface layer of the workpiece to see how the residual stress changes under each temperature. Finally, it was found that when the temperature difference was about 100℃, the residual stress was smaller.

Key words: titanium alloy；electromagnetic induction；heat treatment；Cutting simulation；Residual stress

目录

摘要 2

Abstract 3

第一章 绪论 6

1.1 课题研究背景及意义 6

1.2 电磁感应加热技术概述 6

1.3 钛合金加工工艺概述 7

1.3.1 钛合金的力学性能 7

1.3.2 钛合金的加工特性 7

1.4 残余应力概述 7

1.5 国内外研究现状概述 9

1.6 本文主要研究内容 10

第二章 电磁感应预热加工优化技术 11

2.1 电磁感应加热技术 11

2.1.1 涡流效应 11

2.1.2 趋肤效应 11

2.2 电磁感应加热技术的发展与未来 12

2.3 电磁感应加热技术的优势 13

2.4 有限元数学模型 13

2.4 工件表面预热优化流程 13

2.5 本章小结 14

第三章 Ti6Al4V钛合金切削的有限元仿真 16

3.1 二维正交切削模型的仿真 16

3.1.1 本构模型的选用 16

3.1.2 仿真合金物理参数和刀具参数 16

3.1.3 摩擦模型 17

3.1.4 有限元仿真 17

3.2 二维正交切削模型下影响因素分析 18

3.2.1 外表层与次表层间温度差下的残余应力规律 18

3.2.2 切削速度的影响 20

3.3 本章小结 24

第四章 结论与展望 25

4.1 结论 25

4.2 展望 25

参考文献 26

致谢 28

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