鋁元素及固溶熱處理冷卻速率對單方向凝固CM-247LC鎳基超合金之高溫潛變及氧化特性之研究

Study of Aluminum Element and Solution Heat Treatment Cooling Rate on High-Temperature Creep and Oxidation Behavior of Directionally Solidified CM-247LC Ni-based Superalloy

邱茂盛(Mau-Sheng Chiou)

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/博士(2015年)

https://doi.org/10.6343/ISU.2015.00108

摘要

本研究以合金設計的觀點，選用CM-247LC鎳基超合金為材料基礎，透過熱處理程序的調整及微量元素的改變，探討其高溫潛變及高溫氧化性質的影響與變化。研究結果顯示，添加1 wt.%Al元素於CM-247LC鎳基超合金可促進gamma prime強化相析出，提高體積分率，增強其高溫潛變性質，同時提高了Al活性，促進Al2O3氧化層在高溫下析出且提高了材料的抗氧化性能。而在固溶後不同冷卻速率的影響，冷卻速率越慢，gamma prime強化相會越粗大，而降低的了高溫潛變性質。在高溫及超高溫的潛變測試下，gamma prime相會轉變為rafting結構來抵抗差排移動，但在超高溫中的潛變機制主要還是以擴散為主，而在中溫下並沒有產生rafting結構，潛變機制主要以差排移動為主。

關鍵字

鎳基超合金 ； 合金設計 ； 冷卻速率 ； 高溫潛變 ； 高溫氧化

並列摘要

In this study, CM-247LC nickel-based superalloy was selected as a base material for alloy design, by revising heat treatment process and changing element content, to explore the effects of high temperature creep behavior and high temperature oxidation properties. The results showed that adding 1 wt.% Al element in CM-247LC nickel-based superalloy could promote gamma prime phase precipitation, improve volume fraction, enhance its high temperature creep properties, increase the Al activity, stimulate Al2O3 oxide layer at high temperatures, and advance oxidation resistance. When cooling rate after solution treatment is slower, gamma prime phase becomes thicker; consequently the high temperature creep properties are reduced. In the high temperature and ultra-high temperature creep testing, gamma prime phase was transformed into rafting structure to resist dislocation movement, but diffusion behavior is the main mechanism in the ultra-high temperature. Rafting structure was not produced in intermediate temperature; however the main deformation mechanism is dislocation movement.

並列關鍵字

Nickel-based superalloy ； CM-247LC ； Alloy design ； Cooling rate ； High temperature creep ； High temperature oxidation

參考文獻

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