旋锻钨合金的残余应力及动态力学性能  

Residual stress and dynamic mechanical properties of swaging deformed tungsten alloy

作　　者：林泽华 康俊 周永贵 周承商[1] 闫文敏 LIN Zehua;KANG Jun;ZHOU Yonggui;ZHOU Chengshang;YAN Wenmin(State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China;Shenzhen Zhucheng Technology Co.,Ltd.,Shenzhen 518100,China;Key Laboratory of Transient Shock Technology,No.208 Research Institute of China Ordnance Industry,Beijing 102202,China)

机构地区：[1]中南大学粉末冶金国家重点实验室,长沙410083 [2]深圳市注成科技股份有限公司,深圳518100 [3]中国兵器工业第208研究所瞬态冲击技术重点实验室,北京102202

出　　处：《粉末冶金材料科学与工程》2021年第5期404-411,共8页Materials Science and Engineering of Powder Metallurgy

基　　金：国防科技重点实验室基金资助项目(6142606183209)。

摘　　要：以W、Ni、Fe粉末为原料,采用冷等静压成形和真空烧结工艺制备成分为95W-3.5Ni-1.5Fe的钨合金,然后进行变形量分别为15%、30%和40%的旋锻变形,利用扫描电镜观察、电子背散射衍射分析、X射线衍射分析、霍普金森压杆(SHPB)及实弹靶试等手段分析和测试合金的微观组织、动态力学性能和应力分布。结果表明:钨合金经旋锻变形后,钨颗粒被拉长,从球状变为橄榄状。经过40%变形量的旋锻加工,钨合金的静态抗拉强度与硬度(HRC)分别从983 MPa与28.9提升至1 434 MPa与46.1,伸长率从11.9%下降至4.6%。合金内部存在残余压应力,主要分布在钨颗粒与颗粒之间,以及Ni-Fe黏结相中。旋锻钨合金在应变速率约为1.2×10^(3)s^(-1)下冲击时具有较高的应变率,为4.9%,且在侵彻钢靶时表现出"自锐"性。95W-3.5Ni-1.5Fe tungsten alloy was prepared by cold isostatic pressing and vacuum sintering using W, Ni and Fe powders as raw materials. Then, the swaging processing with 15%, 30% and 40% deformation was carried out.Scanning electronic microscope with electron backscattered diffraction, split Hopkinson pressure bar and live-fire target test were used to analyze the microstructure, dynamic mechanical properties and residual stress distribution of 95 W-3.5 Ni-1.5 Fe tungsten alloy. The results show that the W particles in the tungsten alloy deform from a spherical shape to an olive shape after swaging process. The static tensile strength and hardness(HRC) of the 40% deformation tungsten alloy increase from 983 MPa and 28.9 to 1 434 MPa and 46.1 HRC respectively, and the elongation decreases from 11.9% to 4.6%. There are residual compressive stresses in the alloy, which are mainly distributed between tungsten particles and in the Ni-Fe bonding phase. The deformed tungsten alloy has a higher strain rate of 4.9% under the impact strain rate of about 1.2×10^(3)s^(-1), and exhibits “self-sharpening” when penetrating the steel target.

关 键 词：W-NI-FE合金 旋锻变形 动态力学性能 绝热剪切 微观组织 残余应力 

分 类 号：TF125.2[冶金工程—粉末冶金] TG146.4[冶金工程—冶金物理化学]