(西北有色金屬研究院 鈦合金研究所,西安 710016)
摘 要: 根據(jù)Ti600合金中析出物的特點,設計5種熱處理工藝,研究不同熱處理工藝下合金的蠕變性能。結果表明:Ti600合金經(jīng)1 060 ℃固溶處理后,隨著時效時間的延長,蠕變過程中動態(tài)析出效應逐漸減弱,合金對應的抗蠕變性能增強。在時效過程中,當有a2相形成時,合金具有最強的蠕變強化效應。Si元素無論是以固溶狀態(tài)還是以析出狀態(tài)存在,都具有蠕變強化作用,但固溶狀態(tài)的強化效果優(yōu)于析出狀態(tài)的。固溶后時效時間的不同表明Ti600合金存在不同程度的蠕變動態(tài)析出強化效應,但是這種強化效應也伴隨著析出物形成過程的擴散效應,這種擴散效應抵消了動態(tài)析出的強化效果。因此,為了強化蠕變性能,合金應該在充分時效的情況下使用。
關鍵字: Ti600合金;高溫鈦合金;蠕變;析出物
Ti600 high-temperature alloy
(Titanium Alloy Research Center, Northwest Institute for Nonferrous Metal Research, Xi’an 710016, China)
Abstract:According to the characteristics of precipitates, five heat treatment processes were designed for Ti600 high- temperature titanium alloys, and their creep properties and microstructures were tested after various heat treatments and creep exposure treatments. The results show that, after solution treatment, there is an increasing creep resistance and a decreasing creep dynamic ageing effect with increasing the ageing time. The alloy shows the strongest creep resistant effect when phase a2 forms in Ti600 alloy after ageing treatment for a long time. The Si element in solution or in silicide shows creep resistant effect, and the former is the dominating condition of Si element. The different ageing times indicate different level dynamic creep strengthening effects for alloys. However, the dynamic ageing strengthening effect is accompanied with diffusion effect, and this diffusion effect counteracts the dynamic ageing strengthening effect. Thus, for creep properties, Ti600 alloy should be used under sufficient aging condition.
Key words: Ti600 alloy; high-temperature titanium alloy; creep; precipitate


