(1.中南大學(xué)粉末冶金國家重點實驗室，長沙 410083；
2.中南大學(xué)粉末冶金研究院，長沙 410083；
3.中南大學(xué)材料科學(xué)與工程學(xué)院，長沙410083)
摘 要: 采用差熱分析技術(shù)，研究樣品質(zhì)量和升溫速率對FGH96合金差熱曲線的影響。以FGH96為代表，探索采用差熱曲線分析方法準(zhǔn)確測量粉末冶金高溫合金相變溫度的最佳升溫速率和樣品質(zhì)量。分析和對比差熱曲線不同方法判定的γ′相完全溶解溫度、固相線溫度及液相線溫度。改進(jìn)了固相線判定方法，并在此基礎(chǔ)上確定了FGH96合金中主要相變溫度的最優(yōu)判定方法。實驗測定了FGH96合金熱等靜壓、熱擠壓和熱處理狀態(tài)的相變溫度。結(jié)果表明：FGH96合金在不同狀態(tài)下的相變溫度基本相同。同時，確定了高溫合金差熱分析的兩個重要實驗參數(shù)，提出可統(tǒng)一應(yīng)用于高溫合金差熱曲線分析相變溫度的判定方法。
關(guān)鍵字: FGH96；粉末冶金高溫合金；差熱分析；相變溫度；樣品質(zhì)量；升溫速率；熱力學(xué)計算
（1.State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. Research Institute of Powder Metallurgy, Central South University, Changsha 410083, China;
3.School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The effects of sample mass and heating rate on differential thermal analysis (DTA) curves were investigated. Available methods for determining gamma prime(γ′)solvus, solidus and liquidus were analyzed and compared separately. This study improves methods for determining solidus and identifies optimal methods for measuring temperature of γ′solvus, solidus and liquidus. Transformation temperatures of FGH96 samples prepared by hot isostatic pressing(HIP), hot extrusion(HEX) and heat treatment(HT) were tested. DTA curves do not show significant differences.Appropriate sample mass and heating rate are obtained, and auniversalapplicable analysis method of DTA curves for dermining phase transformation temperatures of powder metallurgy superalloy is proposed.
Key words: FGH96; powder metallurgy superalloy; differential thermal analysis; transformation temperature; sample mass; heating rate; thermodynamic calculation
