准β锻造工艺对TC18钛合金组织与性能的影响  

Influence of quasi β forging on microstructure and mechanical properties of TC18 Ti alloy

作　　者：黄定辉 周俊 洪鑫 陈瑞钢 赵顺峰 

机构地区：[1]无锡透平叶片有限公司,江苏无锡214174

出　　处：《锻压技术》2014年第8期125-128,共4页Forging & Stamping Technology

摘　　要：研究了准β锻造工艺对TC18钛合金显微组织和性能的影响。结果表明：在α＋β两相区较小变形时,其显微组织和仅在β单相区变形时组织形貌相近,为典型的网篮组织;在α＋β两相区较大变形时,晶界破碎程度增大,片状α相向等轴状α相转变;随两相区变形量由0~50%变化时,其抗拉强度先升高再降低,在变形量为20%~30%时抗拉强度较高,塑性则呈小幅上升趋势。TC18钛合金跨相区锻造时,为获得编织均匀的网篮组织,且又保证原始β晶界充分破碎,从而获得较优的强度、塑性和冲击韧性的匹配,在β单相区即Tβ＋20℃温度下的热加工变形中变形量应大于35%,而在α＋β两相区即Tβ-30℃温度下的热加工变形中变形量应控制在30%以内。The influence of quasi β forging on microstructure and mechanical properties of TC18 Ti alloy was studied. Results show that the microstructure in （ α＋ β） two-phase zone with smaller deformation degree is close to the one in β monophase zone and is of typical basket weave. In （α ＋ β） two-phase zone with larger deformation degree, the crushed degree of grain boundary increases, and the trans- formation of α phase from lamellar state to isometrical state occurs. When the deformation degree in two-phase zone varies from 0 to 50%, the tensile strength firstly rises and then drops, and it is higher when deformation degree is within 20% - 30%, while the plasticity of TC18 Ti alloy goes up slightly. When forging with stepping over phase zone for TC18 Ti alloy, to obtain homogeneous basket weave and ensure the original β - grain boundary to be sufficiently broken, which brings about better strength, plasticity and impact ductility for TC18 Ti alloy, the deformation degree should be more than 35% during hot-forming in β monophase zone with Tβ ＋ 20 ℃ and within 30% during hot-forming in （ α ＋ β） two-phase zone with Tβ - 30 ℃.

关 键 词：TC18钛合金 跨相区变形 准β锻造 

分 类 号：TG319[金属学及工艺—金属压力加工] TG146.23[一般工业技术—材料科学与工程]