不同熱處理條件對CP-Ti及Ti-6Al-4V合金電解滲氫行為影響之研究

Effects of different thermal treatment conditions on the electrolytic hydrogenating behavior of CP-Ti and Ti-6Al-4V alloy

施明育(Ming-Yu Shih)

指導教授 ： 吳臺一

大同大學/工程學院/材料工程學系所/碩士(2008年)

摘要

本研究探討不同熱處理條件對電解滲氫後微觀結構及氫原子濃度分佈之變化情形。X光繞射術(X-ray diffractometry; XRD)及輝光放電光譜術(glow discharge optical spectrometry; GDOS)分別用以分析微結構變化及氫原子濃度分佈情形。結果發現：經空氣爐熱處理後表面氧化膜會減損滲氫效率。利用研磨或真空加熱除去氧化膜後再滲氫，則同時提升滲氫量及滲氫深度，且氫原子濃度高峰落在表面下約1.2μm處，其結果與試片直接經真空熱處理者相同，此乃因熱處理造成微結構改變，致使氫原子在CP-Ti及Ti-6Al-4V合金近表面層中的活性產生變異，所以造成此一逆濃度梯度之氫擴散現象。

關鍵字

氫濃度分佈 ； Ti-6Al-4V合金 ； CP-Ti ； 電解滲氫 ； X光繞射術 ； 輝光放電光譜術

並列摘要

Effects of heat treatment on the variations of microstructure and hydrogen distribution of CP-Ti and Ti-6Al-4V alloy (Ti-64) after electrolytic hydrogenation were investigated in this study. X-ray diffractometry (XRD) and glow discharge optical spectrometry (GDOS) were employed in analyzing the microstructural changes and obtaining the hydrogen depth profiles. It was found that the oxide films formed on the specimens after been treated in an air furnace degraded the hydrogen absorption efficiency. Hydrogen uptake and the maximum diffusion depth were simultaneously elevated after applying grinding or vacuum deoxidation. The peak of hydrogen concentration located at about 1.2μm beneath the surface. The similar results were also found in the specimens directly treated in a vacuum furnace. The attribution is thought to be the microstructural change results in the activity variation of hydrogen at the near surface, and thus, induces the up-hill diffusion of hydrogen atoms.

並列關鍵字

CP-Ti ； Ti-6Al-4V alloy ； electrolytic hydrogenati

參考文獻

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