鈦-10鋁合金顯微結構研究

Study on Microstructure of the Ti-10Al Alloy

游昌樺(Chang-Hua Yu)

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(2013年)

https://doi.org/10.6346/NPUST.2013.00152

摘要

本文主要是探討鈦-10鋁合金顯微結構研究：
鑄造鈦-10鋁經過600℃～1050℃熱處理1小時後，觀察其顯微結構，透過掃描式電子顯微鏡(SEM)、X射線繞射儀(XRD)、穿透式電子顯微鏡(TEM)進行觀察，結果如下：
一、經過SEM的觀察，基本上顯微結構為麻田散體的等軸晶層狀結構。麻田散體的晶格常數為a = 0.293～0.298 nm、c = 0.462～0.467 nm，c/a≒1.571。此外，晶粒尺寸大約在3～200μm之間。
二、經過退火溫度在1100℃或以上，一些面心立方晶體結構FCC的析出物在α/α界面上形成。
三、當退火溫度在850℃或以下，在基地可以觀察到一些細微的析出物α2為六方最密堆積HCP結構，值得注意的是析出物α2出現的溫度高於其他研究的學者。

關鍵字

顯微結構 ； 鈦 ； 麻田散體 ； 退火 ； α2

並列摘要

The microstructures of the as-casted Ti-10wt.%Al annealed at temperatures in the range between 600℃ to 1150℃ for 1 hour were examined by using scanning electron microscopy(SEM), X-ray diffractometry (XRD) and transmission electron microscopy(TEM). The results are described as following:
1. Based on the SEM observations, the microstructure of the alloy is essentially martensite (equiaxed-lamella structure). And the TEM lattice parameters of the martensite matrix is a = 0.293~0.298nm, c = 0.462~0.467 nm, c/a ≒1.571. Moreover, the grain sizes were about in the range of 3μm-200μm.
2. For annealing at 1100℃ or above, some precipitates of FCC structure were formed at the interface of α/α.
3. For annealing at 850℃ or below, some fine precipitates of ordered HCP structure (α2) were found within the matrix. It is noted that α2 appears temperature is higher than the other researchers.

並列關鍵字

microstructure ； titanium ； martensite ； annealed ； α2

參考文獻

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