A1070在累進式背擠製下的機械性質與微結構之研究

陳弘志(Hung-chih Chen)

指導教授 ： 葉維磬

國立中央大學/工學院/機械工程學系/碩士(2014年)

摘要

本文對於累進式背擠製(accumulative back extrusion, ABE)製程作出探討，利用自行設計之模具，以實驗的方式對鋁材1070 變形前後的機械性質與微結構的作出探討。
在實驗中，以不同的變形比(deformation ratio)與沖頭行程(die stroke)兩大實驗參數互相搭配下， 對其機械性質與微結構進行探討，機械性質部分主要討論其硬度(hardness)變化，而微結構的部分針對晶粒細化後的晶粒大小(grain size)與晶界取向差異角度(misorientation angle of grain boundaries)進行探討。
實驗結果顯示，越大的變形比與沖頭行程可產生較大的塑性變
形，會產生硬度的提升、晶粒細化的現象與高晶界取向差異角度的提
升。

關鍵字

累進式背擠製 ； 機械性質 ； 微結構

並列摘要

This article is focus on a manufacturing process called
accumulative back extrusion, its experiments are done with
aluminum 1070 and some self-designed molds. The differences of the mechanical property and the microstructure between before and after forming are investigated.
The two main parameters in experiments, deformation ratio
and die stroke, are operating in mutual. The discussion of
mechanical property is focus on the change of hardness. And the part of microstructure is about grain size and the
misorientation.
The results reveal that the larger deformation ratio and die
stroke are, the more plastic deformation are. And that will cause the elevation of hardness, the phenomenon of grain refining and the raise of high misorientation angle of grain boundaries.

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