鈦-4.5鋁-3釩-2鉬-2鐵合金顯微結構探討

Studies of the Microstructure on the Ti-4.5Al-3V-2Mo-2Fe Alloy

林紀綱

指導教授 ： 趙志燁

國立屏東科技大學/工學院/機械工程系所/碩士(2012年)

https://doi.org/10.6346/NPUST.2012.00239

摘要

本文主要利用SEM和TEM儀器，經過不同固溶與時效熱處理，分析鈦-4.5鋁-3釩-2鉬-2鐵合金顯微結構，相關研究結果如下所示︰
一. 合金β/(α+β)轉換溫度約900℃，麻田散鐵轉換溫度(Ms)約825℃。
二. 原料具有α+β雙相結構，在α相基地內觀察到次晶粒及差排。
三. 固溶900℃經不同時效熱處理，低溫時效麻田散鐵有層狀組織之現象，並在基地析出β相晶粒，高溫時效時麻田散鐵產生粗大化現象，此時金相由α'轉變為α+β。
四. 固溶850℃經不同時效熱處理，低溫時效α和α邊界形成界面差排，在α'相晶粒形成高密度差排，高溫時效α'相晶粒形成高密度差排，此時α+α'轉變為α+(α+β)。
五. 固溶800℃經不同時效熱處理，低溫時β相晶粒形成界面差排，在α相形成高密度差排，高溫時效β相形成高密度差排。

關鍵字

β/(α+β)轉換溫度 ； Ms轉換溫度 ； 時效

並列摘要

1. The temperature of theβ/(α+β) and Ms transition is nearly 900℃ and 825℃, respectively.
2. The Microstructures of the raw Ti-4.5Al-3V-2Mo-2Fe alloy is duplex (α+β) phase .
3. Being solution heated treatment at 900℃ and then different aged, coarsening of the martensite.The coarsening of the martensite grain occurred at low temperature aging . The coarsening of the martensite grain and the martensite boundary occurred at low temperature aging.
4. Being solution heated treatment at 850℃and then different aged ,α and α' boundary becoming Interface dislocations of low temperature, α'becoming high density of dislocations of high temperature.
5. Being solution heated treatment at 800℃and then different aged,β becoming interface dislocations of low temperature, α becoming high density of dislocations.β becoming high density of dislocations at high temperature aging.

並列關鍵字

β/(α+β) transition temperature ； Ms transition temperature ； aging

參考文獻

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