文档介绍：摘要

本文主要研究了 2A50 铝合金等径角挤压后微观结构和性能变化。重点探讨
了挤压路径和挤压次数对合金微观结构的影响,同时研究了挤压路径和挤压次数
与合金综合力学性能的关系,此外,考察了挤压路径和挤压次数对合金电导率的
影响。
微观结构分析表明:2A50 铝合金多道次挤压后晶粒明显细化。A 路径的细
化效果优于 Bc 路径。微观组织中细小的第二相主要来自于原始材料中的第二相,
能谱分析的结果表明,第二相所含的主要元素是铝元素和铜元素。X 射线衍射试
验的结果说明,等径角挤压造成原子排列紊乱和晶格常数发生变化,紊乱的程度
和晶格常数的变化和挤压次数和挤压路径有关。
由力学性能测试结果可知:等径角挤压后 2A50 铝合金的综合力学性能发生
变化。随着挤压次数的增加,合金的硬度,抗拉强度都显著增加。经过 Bc 路径
四道次挤压后,合金的硬度由原始的 43HV 上升到 66HV,同时抗拉强度提高了
90%左右。但是,挤压后合金的延伸率会随着挤压次数的增加而下降,尤其是 A
路径四道次挤压后,合金的延伸率下降到 %。Bc 路径挤压后合金的综合力学
性能更好。
电导率测试结果说明:等径角挤压对 2A50 铝合金的电导率有明显的影响。
电导率随着挤压次数的增加而下降。经一道次挤压后,电导率下降的幅度最大,
由原始的下降到 , A 路径挤压后试样的电导率比 Bc 路径挤
压后试样的电导率下降更多。
关键词: 2A50 铝合金,ECAP,微观组织,力学性能,电导率

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ABSTRACT

The main purpose of this investigation is to research the variety of microstructure
and the properties of general mechanics in 2A50 aluminium alloy after the equal
channel angular key point of the paper is to investigate the effect of
different routes and different passses on the microstructure and mechanical
properties,The relationship between mechanical properties and pressing technical
parameters are studied,Meanwhile,the connection of conductance and pressing
technical parameters is discussed too.
Analysis of microstructure shows:the size of grains is obviously decreased after
equal channel angular grains that get from route A is much finer than
the grains which get from route Bc,The fine second-phase that found in the
microstructure is generated from the original second-phase in 2A50 aluminium alloy,
according to the result of EDS ,the main elements of fine deposition are Al and
Cu. The result of XRD illuminate that arranging of atoms e much more chaos
after ECAP, at the same time the constant of grain lattice changed too,all of these
changes are related to the pressing passses and pressing routes.
According to the result of mechanical properties testing,the alloy exhibit good
mechanical properties after