(西安交通大學(xué) 金屬材料強度國家重點實驗室,西安 710049)
摘 要: 采用掃描電鏡(SEM)、透射電鏡(TEM)、X射線衍射(XRD)和顯微硬度儀等技術(shù)對Ti-1300合金不同熱處理工藝的試樣進行了觀察與表征,研究Ti-1300合金的 相對時效過程中β→α相轉(zhuǎn)變及微觀組織與力學(xué)性能的影響。結(jié)果表明:固溶處理的試樣以4 ℃/min的速率加熱到350 ℃保溫10 min,隨后加熱到500 ℃保溫4 h,析出α相的平均尺寸(長度)為54 nm;而直接在500 ℃保溫4 h析出α相的平均尺寸(長度)為202 nm。將固溶后的試樣隨爐加熱(4 ℃/min)到350 ℃,b 相中只有 相析出;加熱到400 ℃時,在組織中發(fā)現(xiàn)了α相依附w相形核現(xiàn)象,加熱到500 ℃保溫4 h時, 相消失,合金獲得極為細小均勻的a相。時效過程中析出的α相對合金的硬化作用比w相的更為顯著。
關(guān)鍵字: Ti-1300合金;時效;w相;α相形核
(State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China)
Abstract:The microstructures of the aged samples after solution treatment with different aging treatments were observed and characterized by SEM, TEM and XRD. The effects of ω phase on the β→α phase transformation and microstructures on Ti-1300 alloy were also studied. The results show that the average size (length) of precipitated α phase is 54 nm after being heated at 350 ℃ for 10 min and then being heated at 500 ℃ for 4 h. The average size (length) of the α phase is 202 nm when the sample is directly held at 500 ℃ for 4 h. Only nanoscale w phase were observed in the sample being heated to 350 ℃ at the rate of 4 ℃/min, while α phase nucleation attached to w phase was observed in the sample which is heated to 400 ℃. When the sample is heated continuously to 500 ℃ and held for 4 h, w phase disappeared and very fine uniform α precipitates are obtained in the microstructure. The hardening effect of α phase is stronger than that of w phase.
Key words: Ti-1300 alloy; aging; w phase; α phase precipitation


