(中南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 采用形變熱處理法制備01420鋁鋰合金細(xì)晶板材，研究時(shí)效第二相對(duì)位錯(cuò)分布和層狀再結(jié)晶組織形成的影響。結(jié)果表明：時(shí)效第二相沿板材法向呈梯度分布，在表面層分布均勻且含量較大，而在中心層主要沿平行軋制方向分布且含量較小；第二組粒子的這種分布方式導(dǎo)致軋制過(guò)程中在其周圍形成的高應(yīng)變區(qū)域也呈梯度分布，這是導(dǎo)致層狀再結(jié)晶組織形成的主要原因；板材表面層為細(xì)小等軸的再結(jié)晶晶粒，平均粒徑約為10 μm；板材中心層再結(jié)晶晶粒呈長(zhǎng)條狀，平均尺寸約為30 µm×12 µm；各層約占板材總厚度的1/3。
關(guān)鍵字: 01420 鋁鋰合金；層狀晶粒組織；晶粒細(xì)化；形變熱處理；粒子激發(fā)形核
（School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:Abstract: Fine grained 01420 Al-Li alloy sheet was produced by thermo-mechanical processing. The precipitation behavior of the second phase particles and their effects on the distribution of dislocations and gradient recrystallized grains were investigated. The results show that after aging, a gradient distribution of the large particles through the thickness occurs. The particles in the surface layer (SL) distribute homogeneously with larger content whereas the particles in the center layer (CL) mainly distribute parallel to the rolling direction with smaller content. The subsequent rolling results in a corresponding gradient distribution of high strained regions around these particles, which is the main reason for the formation of the gradient grain structure. The SL contains a fine, equiaxed grain structure with an average grain diameter of 10 μm whereas CL contains coarse elongated dimension with average grain size of 30 µm ×12 µm, each layer accounts for about 1/3 of the whole thickness
Key words: 01420 Al-Li alloy; layered grain structure; grain refinement; thermo-mechanical processing; particle stimulated nucleation (PSN)
