本文選題：快速凝固 + 粉末冶金�。� 參考：《稀有金屬材料與工程》2015年01期

【摘要】：針對(duì)Ti-5.8Al-4.8Sn-2Zr-1Mo-0.35Si-0.70Nd粉末冶金高溫鈦合金中富釹稀土相的形成、尺寸、分布、形態(tài)、長大及結(jié)構(gòu)特征進(jìn)行了系統(tǒng)研究。結(jié)果表明:快速凝固態(tài)高溫鈦合金粉末中稀土相為液態(tài)析出相,其尺寸大部分在50~250 nm之間,彌散分布在基體中;晶內(nèi)稀土相多為球狀,晶界稀土相多為橢球狀,其長軸平行于晶界;TEM觀察到的稀土相的尺寸和分布與理論計(jì)算相符合;快速凝固高溫鈦合金粉末經(jīng)過700~1000℃/110 MPa/0.5 h熱等靜壓成形后,快速凝固過程中已析出的稀土相尺寸變化不大;同時(shí)細(xì)小的稀土相從過飽和的基體中大量固相析出;經(jīng)過1200℃/140 MPa/3 h熱等靜壓成形后,稀土相顆粒尺寸大部分在150~500 nm之間,有明顯長大;稀土相的高分辨圖像及同心衍射環(huán)花樣表明,快速凝固高溫鈦合金粉末中的稀土相由5~10 nm的納米晶組成,經(jīng)過1200℃熱等靜壓成形處理后的稀土相仍由納米晶組成,而且納米晶的尺寸沒有明顯變化;但是稀土相的"基體"上明顯出現(xiàn)富Sn元素的"第二相"顆粒,結(jié)構(gòu)變得復(fù)雜。
[Abstract]:The formation, size, distribution, morphology, growth and structural characteristics of neodymium rich rare earth phase in Ti-5.8Al-4.8Sn-2Zr-1Mo-0.35Si-0.70Nd powder metallurgy high temperature titanium alloy were systematically studied. The results show that the rare earth phase is liquid precipitated phase in solidified solid high temperature titanium alloy powder, and its size is mostly between 50 ~ 250 nm and dispersed in the matrix, the rare earth phase in crystal is mostly spherical, and the rare earth phase in grain boundary is ellipsoid. The size and distribution of rare earth phase observed by TEM with long axis parallel to grain boundary are in agreement with the theoretical calculation, and the rapidly solidified high temperature titanium alloy powder is formed by hot isostatic pressing at 700 鈩，

本文編號(hào)：1862711