80W-10Ta-7Ni-3Fe高密度合金研究

Study of 80W-10Ta-7Ni-3Fe High Density Alloys

用金相显微镜,扫描电镜,X 射线衍射及密度测定,研究了 90W-7Ni-3Fe 和 80W-10Ta-7Ni-3Fe 2 种成分合金。结果表明,含 Ta 合金在 1 400℃烧结时密度可达 96.3%,合金密度随烧结温度提高而增加,在 1 460℃时密度达到最大;Ta 原子固溶到硬质相 W 和粘结相中,使得合金硬度明显提高;含 Ta 合金断口形貌中,粘结相呈沿晶断裂、W 晶粒穿晶断裂及其脱出具有相当比例;Ta 粉末粒度对合金力学性能、微观组织及断裂方式均产生显著影响。

90W-7Ni-3Fe and 80W-10Ta-7Ni-3Fe alloys were studied by metallographic microscope, scanning electron microscope, x-ray diffraction and density measurement. The results show that density is up to 96.3% when specimen containing Ta is sintered at 1 400degreesC.The alloy density increases with the increase of sintering temperature, and highest as green is sintered at I 460degreesC and the alloy is much harder due to the solution of tantalum in W and matrix phases. Matrix intergranular rupture, tungsten cleavage and tungsten-matrix interfacial separation are all prominent in the fractographs of alloy with Ta addition; and Ta particle size has visible effect on the properties, microstructure and rupture mode of the alloy.