去应力退火工艺对锻造TA7钛合金切削性能的影响  

Influence of Stress Relieving Annealing Process on Forging TA7 Titanium Alloy Machinability

作　　者：孙富建 肖罡 蒋志贤[1,2] 李时春 万可谦[3] SUN Fujian;XIAO Gang;JIANG Zhixian;LI Shichun;WAN Keqian(Intelligent manufacturing institute,Hunan University of Science and Technology,Xiangtan 411201;School of Mechanical Engineering,Hunan University of Science and Technology,Xiangtan 411201;Jiangxi KMAX Industrial Co.,Ltd.,Nanchang 330100;State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,Hunan University,Changsha 410082)

机构地区：[1]湖南科技大学难加工材料湖南省重点实验室,湘潭411201 [2]湖南科技大学机电工程学院,湘潭411201 [3]江西科骏实业有限公司,南昌330100 [4]湖南大学汽车车身先进设计制造国家重点实验室,长沙410082

出　　处：《机械工程学报》2022年第13期298-306,共9页Journal of Mechanical Engineering

基　　金：国家自然科学基金青年基金(51805165,52075159);湖南省自然科学基金青年基金(2019JJ50195)资助项目。

摘　　要：TA7钛合金(Ti-5Al-2.5Sn)在退火状态下具有良好的室温和高温断裂韧度,而锻造TA7钛合金必需经过去应力退火,才能进行切削加工,去应力退火成为锻造工序与切削加工工序间的中间环节,通过微观结构的变化能够调控力学性能和切削加工性能。在600℃、800℃、1000℃下对锻造TA7钛合金进行去应力退火,获得了三种不同的微观组织。800℃试样的细小次生α相和等轴初生α相降低了切削温度、切削力,加剧了切屑的锯齿状结构的形成;1000℃试样的片状β相和粗大α相降低了切削温度,增大了切削力,恶化了切屑的锯齿状结构,但降低了切屑的凸起角和剪切应变。TA7 titanium alloy(Ti-5Al-2.5Sn)has excellent room temperature and high temperature fracture roughness in annealed state.Especially,after undergoing stress relieving annealing the forging TA7 titanium alloy can be machined.The stress relieving annealing is a link between the forging process and machining process,can regulate and control the mechanical properties and machinability of workpiece through the change of microstructure.In this paper forging TA7 titanium alloy was stress relieving annealed at the temperatures of 600℃,800℃,1000℃,three microstructures were gained.The fine secondaryαphase and equiaxed primaryαphase of the 800℃specimen reduced cutting temperature and cutting forces,intensified the formation of the chip serrated structure.The lamellarβphase and coarseαphase of the 1000℃specimen decreased the cutting temperature,increased the cutting forces,intensified the formation of the chip serrated structure,but reduced the chip bulge angle and the chip shear strain.

关 键 词：TA7钛合金 去应力退火 微观结构 力学性能 切削加工性能 

分 类 号：TG506[金属学及工艺—金属切削加工及机床]