作　　者： ; ; ; ;

机构地区： 中南大学材料科学与工程学院粉末冶金国家重点实验室

出　　处： 《粉末冶金材料科学与工程》 2013年第6期801-806,共6页

摘　　要： 采用复压复烧工艺制备粉末冶金Fe-2Ni-1Cu-0.6C合金，考察Cu3P添加剂及不同粒度的铜粉在材料制备过程中的存在形式与演变过程，以及它们对合金显微组织与力学性能的影响。结果表明：Fe-2Ni-1Cu-0.6C合金经复压复烧后密度为7.46~7.52 g/cm3。与添加颗粒相对粗大的电解铜粉相比，添加超细铜粉可提高合金的一次压制密度与铜元素在合金中的分布均匀性，烧结体的强度相应提高。800℃预烧时压坯中的Cu3P与铜及其它合金元素反应生成液相，合金元素易扩散进入铁基体内形成固溶强化，导致预烧坯的复压密度随Cu3P含量的增加而下降。添加少量的Cu3P可提高铁基烧结合金的抗弯强度，所制备Fe-2Ni-1Cu-0.6C合金的抗弯强度最高为1262 MPa。而合金的冲击韧性随Cu3P含量增加而下降，从不添加Cu3P时的9.5 J/cm2下降至Cu3P的添加量为1.16%（质量分数）时的3.9 J/cm2。 Powder metallurgical Fe-2Ni-1Cu-0.6C alloy was prepared by double press/double sinter （DP/DS） processing. The existing forms and evolution of Cu3P additive and Cu powder with different sizes in material preparation, as well as their effects on microstructure and mechanical properties of the iron-based alloy were investigated. The results show that, the double pressed/double sintered Fe-2Ni-1Cu-0.6C alloys are 7.46~7.52 g/cm3 in density. Compared with samples contain relatively coarse electrolytic copper particles, samples with ultrafine copper powder get higher green density and uniformity of copper distribution in the iron-based matrix, and the strength of the sintered compact is improved accordingly. Due to the liquid phase generated from Cu3P, copper and other alloy elements at the pre-sintering temperature of 800 ℃, the alloying elements are apt to diffuse into the iron-based matrix to form a solid solution strengthening, which leads to the decrease of double pressing density of pre-sintering compact with increasing Cu3P content. The bending strength of the iron-based sintered alloy is improved by adding minor Cu3P with the maximum bending strength of 1 262 MPa. The impact toughness of the alloy decreases from 9.5 J/cm2 to 3.9 J/cm2 with increasing Cu3P content from 0 to 1.16%.

关 键 词： 粉末冶金 铁基 复压复烧 显微组织

领　　域： [冶金工程] [冶金工程]