單方向凝固CM247LC鎳基超合金添加不同比例鋁元素高溫氧化行為研究

Effects of Different Proportions Aluminum Addition on the High Temperature Oxidation Behavior of Directionally Solidified CM247LC Ni-based Superalloy

顏嘉緯(Chia-Wei Yen)

指導教授 ： 簡賸瑞

共同指導教授 ： 郭振明 ； 葉安洲(An-Chou Yeh)

義守大學/理工學院/材料科學與工程學系/碩士(2016年)

摘要

本研究採用CM247LC鎳基超合金作為材料基底在添加不同比例的鋁元素(0.5wt.%、1wt.%、1.5wt.%、2wt.%)在真空感應熔煉爐(VIM) 中熔煉出CM247LC鎳基超合金添加鋁元素的鑄錠，經線切割後再利用單方向凝固鑄造(DS)，使試棒呈現單方向晶，再進行三階段熱處理，熱處理條件為第一階段固溶熱處理條件為1260℃/2hr/Ac，第二階段為一次時效條件為1050℃/4hr/Ac，第三階段為二次時效條件為800℃/20hr/Ac，上述三階段升溫速度皆為7℃/min，熱處理後試片經切割、研磨至厚度5mm，利用高溫恆溫氧化實驗模擬陸上發動機渦輪葉片在高溫工作環境下的情形，氧化後試片運用掃描式電子顯微鏡(SEM)進行成分分析及微觀組織觀察，從試片剖面圖來觀察，能比較出不同的高溫氧化時數與添加不同wt.% Al氧化層的差別。

關鍵字

鎳基超合金 ； 鋁元素添加 ； 單方向凝固 ； 高溫氧化

並列摘要

In this study, we use CM247LC nickel-based superalloy as a material base in adding different proportions of elemental aluminum (0.5wt.%, 1wt.%, 1.5wt.%, 2wt.%), and use vacuum induction melting (VIM) melting the CM247LC nickel-based superalloy adding aluminum element ingot, and use directionally solidified casting (DSC) CM247LC adding Al element, and then do the three-stage heat treatment, first stage is solution haet treatment conditions for the 1260℃/2hr/Ac, the second stage an aging condition of 1050℃/4hr/Ac, the third stages of secondary aging condition of 800℃/20hr/Ac, all of the three stages of heating rate are 7℃/min, after heat treatment, specimen were made in thickness of 5mm to do isothermal oxidation experiments.
To observe the oxidation behavior of CM247LC adding Al element the microstructure and composition an analysis, we were use scanning electron microscope (SEM) and EDX to observe the microstructure, and cross-sectional view, to compare a different oxidation hours and different wt.% Al adding oxide layer difference.

並列關鍵字

Nickel-based superalloy ； CM247LC ； Al element adding ； directionally solidified casting ； high-temperature oxidation

參考文獻

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