摘要：现社会铜合金材料在众多工业产业等领域有着广泛地应用。结构零部件、强度导线等选材都离不开铜合金材料。一直以来，铜合金加工的工艺方法使得铜合金的强度与导电性存在一定的矛盾，即提高材料强度的同时，那么材料导电性会下降，若加强铜合金导电性，那强度会下降。本文研究一种冷加工工艺，等通道弯角挤压（ECAP），即剧烈塑性变形方法，是将棒状材料挤入模具，再用压力机将材料通过L型通道，材料在模具转角处受到强烈剪切变形，从而积累大量位错，细化材料晶粒，增强铜合金硬度。与其他材料加工工艺相比，ECAP工艺较为简便，加工成本低。而且ECAP处理过的材料气孔少，使得材料组织均匀、致密。本文研究了ECAP工艺处理后铜合金的硬度和导电性数据，并通过电子背散射衍射分析（EBSD）和透射电子显微镜（TEM）观察分析铜合金的微观组织结构演化，从结构与性能角度分析了EPCA工艺制备多尺度优异性能铜合金。

关键词：等通道弯角挤压；电子背散射衍射分析；剧烈塑性变形；细化晶粒

毕业设计说明书外文摘要

Title  Multi Scale Structure Optimization for Controlling High  Strength and High Conductivity of Copper Alloy

Abstract：Social copper alloy materials in many industrial industries and other fields have a wide range of applications.Structural components,strength wire and other materials are inseparable from the copper alloy material.All along,the copper alloy processing method makes the strength and conductivity of copper alloy there is a certain contradiction,that is,to improve the strength of the material at the same time,then the material conductivity will decline,if the strengthening of copper alloy conductivity,that strength will decline.In this paper,we study a cold working process,such as Equal Channel Angular Pressing (ECAP),that is, the method of intense plastic deformation is to squeeze the rod material into the mold,and then press the material through the L-shaped channel,the material at the mold corner by the strong shear Cut deformation,thus accumulating a large number of dislocations,refine the material grain,enhance the hardness of copper alloy.Compared with other materials processing technology,ECAP process is relatively simple,low processing costs.And ECAP treated material less pores,making the material tissue uniform,dense.In this paper, the hardness and conductivity data of copper alloy after ECAP treatment were studied.The microstructure evolution of copper alloy was observed by Electron Backscatter Diffraction(EBSD) and transmission electron microscopy(TEM).From the perspective of structure and performance,Preparation of multi - scale excellent performance copper alloy by EPCA process.

Keywords:ECAP；EBSD；Severe plastic deformation；Refined grain

目   次

1  引言 1

1.1  强化铜合金的方法 1

1.1.1  加工硬化 1

1.1.2  固溶强化 1

1.1.3  细晶强化 2

1.1.4  第二相强化 2

1.2  剧烈塑性变形法（SPD） 3

1.3  SPD方法制备Cu-Cr-Zr合金 4

2  理论分析部分 5

2.1  ECAP力学机理 5

2.1.1  刚塑性/刚粘塑性材料基本假设 5

2.1.2  塑性力学基本方程 5

2.1.3  滑移线法 6

2.2  挤压过程挤压件网格几何形状变化 7

2.3 挤压工艺路线 8

3  实验部分 10

3.1  ECAP实验及处理方法 10

3.1.1  原材料 10

3.1.2  挤压工艺 10

3.1.3  变形道次 10

3.2力学性能测试 12

3.3  电学性能测试 14

3.4  实验总结 15

4  微观组织分析 16

4.1  电子背散射衍射分析（EBSD）技术简介 16

4.2  ECAP处理后铜晶体结构观测 16

4.3  铜合金的透射电子显微镜观测 17