A356鋁合金及含鈧鋁合金半固態製程之研究

The study of semisolid processes of A356 Aluminum Alloy and aluminum alloy containing scandium

黃志瑋(Chih-Wei Huang)

指導教授 ： 邱傳聖 ； 洪衛朋

元智大學/工程學院/機械工程學系/碩士(2005年)

摘要

本研究在探討鑄造用鋁合金A356及鍛造用鋁合金M9 (Al-7.81Zn -2.36Mg-1.9Cu-0.11Zr-0.06Sc wt.％)經半固態製程之變化。以鑄錠、擠型材製備球狀晶材料，觀察其顯微結構的變化、固相率和球狀晶尺寸大小，以球狀晶小於50μm為目標。
A356及M9鋁合金可由應變熔化活化法(SIMA)達到細小球狀晶結果。M9鋁合金的顯微結構無明顯的液相區，A356鋁合金液相區極為明顯。而擠型材經半固態熱處理會產生長條晶，造成材料的流動性變差，甚至在壓鑄過程中長軸晶會破裂造成巨觀的裂縫。因此不適用於半固態製程。

關鍵字

半固態 ； 鍛造用鋁合金 ； 鑄造用鋁合金 ； 球狀晶 ； 鋁鈧合金

並列摘要

This study investigated the variations of casting aluminum alloy A356 and wrought aluminum alloy M9 (Al-7.81Zn-2.36Mg-1.9Cu-0.11Zr-0.06Sc wt.％) by semisolid process. The spherical grains were formed by casting and extrusion. The solid fraction and the size of spherical grain were observed. The purpose of this study was size of spherical grain smaller than 50μm.
The fine spherical grains of A356 and M9 aluminum alloy were gained by strain-induced melt activation (SIMA). The region of liquid of M9 aluminum alloy was not conspicuous, but the region of liquid of A356 aluminum alloy is conspicuous. The long grains were produced in extrusion by the semisolid heat treatment. The long grains conduced to decreased flow. The macro-segregation produced by the long grain cracked in the die-casting. The long grain does not suit with semisolid process.

並列關鍵字

semisolid ； casting aluminum alloy ； wrought aluminum alloy ； spherical grain ； aluminum alloy containing scandium