材料期刊网

本文以亚稳型β钛合金Ti-18Nb-4Sn(原子分数, %)为对象, 研究了75%热轧后再进行75%和97%冷轧,以及在800 ℃不同时间退火对其织构的影响。结果表明, 经过不同程度冷变形后, 试样出现了{112}<110>, {223}<110>,{111}<110>和{111}<112>型轧制织构. 随变形量增加, 轧制织构强度均有所增强,其中以{223}<110>型织构强度增加的幅度最大. 800 ℃退火对75%冷轧试样的织构类型和强度影响不显著, 而对97%冷轧试样的织构产生强烈影响, 形成了单一的高强度的{111}<112>再结晶织构. 该织构在退火5 min后就达到稳定, 延长退火时间到1 h对其强度变化无明显影响. 分析表明, 热轧决定了随后冷轧和退火过程中织构类型的变化, 而大变形量的冷轧以及随后的退火促进了高强度{111}<112>再结晶织构的形成.

The microstructures, phase structures and textures of Ti-18Nb-4Sn alloy after cold rolling reduction of 75% and 97% respectively and annealing at 800℃ for different time were measured. It was found that after cold deformation, the sample remained as a single body-centered cubic β phase structure and had rolling texture, and microstructures were characterized by rolling lines. With increasing cold rolling reduction, the intensity of rolling texture changed from weak to strong, At the reduction of 97%, rolling texture were mainly {223} <110> and {112}<110>. After annealing at 800℃ for five minutes, recrystallization was occurred in the samples, and microstructures were made of a large number of equiaxed recrystal grain. After annealing at 800 ℃ for one hour, the recrystallized grain grew. Texture analysis showed that the annealing can not significantly affect the texture of the lower reduction sample, while the texture intensity of the high reduction sample rose sharply after annealing, and a particularly strong annealing texture {111}<112> appeared in the samples. After annealing at 800 ° C for five minutes, the texture state of the high reduction sample was stabilized, and not changed even annealing time extended to one hour.