轧制及退火对Ti-18Nb-4Sn合金织构的影响

EFFECTS OF ROLLING AND ANNEALING ON THE TEXTURE OF Ti-18Nb-4Sn ALLOY

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 textures of Ti-18Nb-4Sn（atomic fraction,%）alloy were investigated under the conditions of the hot rolling 75%,and then the cold rolling 75% and 97%,and finally the annealing treatment at 800℃.It was found that after the cold rolling,the{112}〈110〉,{223}〈110〉,{111}〈110〉 and{111}〈112〉rolling texture appeared.With increasing the cold rolling reduction the intensity of the rolling textures increased,the largest increase of the intensity was observed in the{223}〈110〉 texture. After annealing at 800℃,the texture type and intensity of the 75% cold rolling sample varied slightly, while the texture type and intensity of 97% cold rolling sample changed significantly,and only a strong {111}〈112〉 recrystallization texture existed,the intensity of which got maximum after 5 min annealing at 800℃and kept almost the same even after 1 h annealing.Analysis indicated that the hot rolling played a crucial role in the formation and transformation of the cold rolling and annealing texture, and cold rolling with large reduction and the subsequent annealing promoted the formation of the high-intensity{111}〈112〉recrystallization texture.