退火和冷变形工艺对7075T73铝合金线材组织性能的影响

Effect of annealing and cold deformation on microstructure and properties of 7075T73 aluminum alloy wires

研究了退火和冷变形工艺对7075T73铝合金线材晶粒组织的影响,并探讨晶粒形貌对合金弯曲性能的影响:7075T73铝合金线材制备过程中,增加冷变形前退火工序,有效地提升合金的再结晶程度;增加冷变形量,也提高合金的再结晶程度和细化晶粒尺寸。采用退火+大冷拉拔变形工艺路线,有效地提高合金的再结晶分数和细化晶粒尺寸,提升7075T73铝合金线材的成形性能。7075T73铝合金线材的晶粒形貌对紧固件成形开裂的影响显著,完全再结晶晶粒形貌能有效提高合金的塑性变形能力、降低缺口敏感性,抑制成形过程中的裂纹开裂和扩展。

The effects of annealing and cold deformation processes on the grain structure of 7075T73 aluminum alloy wires were studied,and the influence of grain morphology on the bending performance of the alloy was explored.The recrystallization fraction of 7075T73 alu⁃minum alloy wires can be improved effectively by adding the annealing procedure before cold deformation.The increase of the cold deformation also improves the recrystallization fraction and refine the grain size.7075T73 alloy wires under annealing and large cold drawing de⁃formation has better recrystallization fraction,finer grains,and improved forming perform⁃ance.The grain morphology of 7075T73 aluminum alloy wires has a significant impact on the forming cracking problem of fasteners.The fully recrystallized grain morphology effectively improves the plastic deformation ability,reduces notch sensitivity of the alloy,and inhibits the crack cracking and propagation during the forming process.