(中南大学 粉末冶金国家重点实验室，长沙 410083)
摘 要: 以高能球磨粉末为原料，研究元素钴对固溶淬火态93W-Ni-Fe合金微观结构和性能的影响。对经1 490 ℃烧结并保温90 min的试样在1 280 ℃固溶2 h，随后在水中淬火，采用光学金相(OM)、扫描电镜(SEM)及EDAX能谱等对样品的组织形貌进行表征，采用准静态拉伸实验对合金的拉伸强度及伸长率进行测试，采用排水法对合金的相对密度进行测量。结果表明：当Co含量为0~0.9%(质量分数)时，随着Co含量的增加，固溶淬火态93W-Ni-Fe合金的拉伸强度、伸长率和相对密度由不添加Co时的1 039 MPa、18.3%和99.3%分别提高到0.9%Co时的1 085.5 MPa、26.5%和99.4%；元素Co的适量加入能增加固溶淬火态合金中钨晶粒的穿晶解理断裂和粘结相的延性撕裂，改善合金组织，提高合金的性能；当元素Co含量超过0.9%时，随着Co含量的增加，固溶淬火态93W-Ni-Fe合金的性能降低；当Co含量为1.5%时，合金的拉伸强度降至1 039.5 MPa，伸长率降至24.6%。
关键字: 93W-Ni-Fe合金；Co；固溶淬火； 微观组织；力学性能
（State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:The effects of Co addition on microstructure and mechanical properties of 93W-Ni-Fe alloy treated by solid-solution and water-quenching were investigated. The procedure, which was 2 h solid-solution at 1 280 ℃ and quickly quenching in water for samples sintered at 1 490 ℃ for 90 min, was performed. Optical microscope(OM), scanning electricity microscope (SEM) and EDAX energy spectrum were used to characterize the microstructure and compositions of the alloys, respectively. The strength and elongation of alloys were tested with quasi-static tensile testing machine, and the relative densities of the alloys were evaluated by using the Archimedes water immersion method. The results indicate that, when Co addition is in the range of 0−0.9%(mass fraction), with the increase of Co content, the tensile strength, elongation and relative density of 93W-Ni-Fe alloys treated by solid-solution and water-quenching increase from 1 039 MPa, 18.3% and 99.3% without Co addition to 1 085.5 MPa, 26.5% and 99.4% with 0.9%Co addition, respectively. Meanwhile, the mechanical properties are enhanced with some Co additions because of increasing the transcrystalline fracture and ductile tearing of the matrix in the solid-solution and water-quenching alloy. When the Co content exceeds 0.9%, the mechanical properties of 93W-Ni-Fe alloy treated by solid-solution and quenching are reduced, so the tensile strength and elongation of alloys reduce to 1 039.5 MPa and 24.6%, respectively with 1.5%Co addition.
Key words: 93W-Ni-Fe alloy; Co; solid-solution water-quenching; microstructure; mechanical properties
