(北京航空材料研究院，北京 100095)
摘 要: 用掃描電鏡、能譜儀、X射線衍射技術(shù)和定量金相技術(shù)研究Ni-10Co-7.1W-1.7Mo-0.5Nb-6.9Ta-7.9Re-6.9Al- 0.008CNi3Al基高溫合金的顯微組織。實(shí)驗(yàn)表明：該合金由γ，γ′，γ + γ′共晶和Re3W相組成；Re是強(qiáng)負(fù)偏析元素，過量Re促使Re3W相的形成；合金中次生γ′、共晶γ′的固溶溫度分別為1 330和1 360 ℃。采用1 290 ℃，2 h+ 1 330 ℃，6 h+1 360 ℃，6 h多級(jí)固溶處理實(shí)現(xiàn)γ′完全固溶并避免初溶，但該處理不能消除Re3W相，也不能實(shí)現(xiàn)Re的完全均勻化，適當(dāng)降低Al,Ta和Re含量可以消除Re3W相。
關(guān)鍵字: Ni3Al基高溫合金；錸；固溶處理；顯微組織
（Beijing Institute of Aeronautical Materials, Beijing 100095, China）
Abstract:The microstructure of Ni3Al base superalloy with composition of Ni-10Co-7.1W-1.7Mo-0.5Nb-6.9Ta-7.9Re- 6.9Al-0.008C was investigated by SEM, EDS, XRD and quantitative metallographic method. The results show that the alloy consists of γ, γ′, eutectic (γ+γ′) and Re3W phases. Rhenium is a strong negative segregation element and the excessive amount of Re promotes the formation of Re3W phase. The solid solution temperatures of secondary γ′, eutectic γ′ are 1 330 ℃ and 1 360 ℃ respectively. By means of 1 290 ℃, 2 h+1 330 ℃, 6 h+1 360 ℃, 6 h multistep solid solution treatment, the full solid solution of γ′ phase is realized and the incipient melting is avoided. However, the Re3W phase can not be eliminated and the homogenization of Re is not completed by the above mentioned treatment. The proper solution is to modify the alloy composition so as to eliminate Re3W phase.
Key words: Ni3Al base superalloy; rhenium; solid solution treatment; microstructure
