摘要
以还原钨粉、羰基镍粉和羰基铁粉为原料,采用微波烧结和常规液相烧结法制备90W-7Ni-3Fe高密度合金,对比研究该合金的变形现象及相对密度和硬度,并对合金样品顶部和底部区域的SEM照片进行分析。结果表明:在温度1 500℃和保温10 min的条件下,经微波烧结的合金变形现象得到有效控制,垂直收缩率偏差和水平收缩率偏差分别为0.21%和0.72%,而常规烧结的垂直收缩率偏差和水平收缩率偏差分别为1.23%和3.25%;微波烧结样品的相对密度为99.88%,略高于常规烧结的99.48%;微波烧结合金的硬度(HRC)比常规烧结高2.3,平均晶粒尺寸比常规烧结低5.88μm;并且,微波烧结样品顶部与底部的液相含量、接触度、晶粒尺寸以及硬度的差异均较小,表明微波烧结的合金晶粒细小、组织均匀。
90-W-7Ni-3Fe heavy alloys were fabricated by microwave sintering and conventional sintering using W,Ni and Fe element powder as raw materials.The distortion,relative density and hardness of 90W-7Ni-3Fe heavy alloys sintered by two methods were studied in the present paper.The top and bottom region of microwave and conventional sintered samples were analyzed by SEM.Both experiment for two sintering methods are carried out at 1 500 ℃ for 10 min.The results show that the distortion is slighter in microwave sintering process than that of in conventional sintering,The relative density and hardness（HRC） of microwave sintering sample is 99.88% and 32.3,respectively,which are both higher than that of conventional sintering sample.The average grain size of microwave sintering sample is smaller than that of conventional sintering sample.Moreover,compared to conventional sintering,the discrepancy of liquid fraction,congruity,grain size and hardness between top and bottom of the microwave sintered sample is much less.So,90W-7Ni-3Fe with fine grain and homogeneous microstructure can be obtained by microwave sintering.
出处
《粉末冶金材料科学与工程》
EI
2010年第3期300-304,共5页
Materials Science and Engineering of Powder Metallurgy
基金
中国博士后科学基金资助项目(20060400882)
