【摘要】 采用扫描电镜(SEM)、X射线能谱仪(EDS)等,研究在氢气保护、真空烧结条件下添加不同含量的Co、La合金元素对90W-Ni-Fe合金显微组织及性能的影响。结果表明:加入适量的Co、La元素,可以改善粘结相与钨颗粒间的润湿性,La以固溶强化的方式强化钨颗粒及粘结相,从而提高了合金性能。当Co、La元素含量为1.1%(质量分数)时,合金中出现了La的富集与氧的偏析,导致合金性能降低;当添加0.7%的Co、La时,试样强度及伸长率出现极大值,分别为930MPa和24.0%;添加0.5%的Co、La时,试样相对密度出现99.30%的极大值。更多还原

【Abstract】 By using scanning electron microscope(SEM) and X-ray energy dispersion spectrometer(EDS),etc,the influences of Co and La additions on mechanical properties and microstructure of 90W-Ni-Fe tungsten alloys sintered in hydrogen and vacuum atmosphere were studied.The results show that the mechanical properties are improved by adding 0.7%(mass fraction) of Co and La,especially the elongation rate and the tensile strength whose ultimate values are 24% and 930 MPa,respectively;the results also reveal that the additions exist in matrix and tungsten grains,which can improve the elongation rate by reducing the continuity of tungsten grains,and strengthen the matrix and tungsten grains by solid solution strengthening,consequently the mechanical properties of the alloy are improved.When 1.1%(mass fraction) of Co and La are added,a kind of intergradation which enriches La appears in the alloy.In addition,by adding 0.5%(mass fraction) Co and La,the alloy gets it′s ultimate relative density of(99.30%.)更多还原