摘要
采用亚微米级Fe2O3粉末作为烧结助剂制备Fe-Ni-Cu-C预混合粉,考察Fe2O3颗粒在混合料中的分布状态、Fe2O3添加量对材料的成形与烧结密度以及显微组织和力学性能的影响。结果表明,亚微米Fe2O3粉末可均匀分布在预混料中,但当Fe2O3粉末添加的质量分数超过0.3%时材料的压制与烧结密度明显下降;添加少量的亚微米Fe2O3粉末可提高合金的力学性能,Fe2O3粉末的添加量为0.3%时,合金的强度、韧性和伸长率较未添加Fe2O3粉末时分别提高7.3%、5.8%和4.8%;由于亚微米Fe2O3还原成微细铁粉后具有高活性,坯体烧结时铁基颗粒间的烧结连接率增大,拉伸断口形貌呈较多的韧窝组织,且烧结体中的孔隙圆化。
Fe-Ni-Cu-C premix powders were prepared with sub-micron Fe2O3 powders as a sintering aid. Distribution status of Fe2O3 particles in the premix, effect of Fe2O3 content on the green and sintered density, and the microstructure and mechanical properties of the sintered materials were investigated. The results show that the sub-micron Fe2O3 particles distribute uniformly in the premix, while the green and sintered density decrease obviously when the Fe203 content is above 0.3%. Compared with that of sample with no Fe2O3 powder adding, the mechanical properties of the alloy are improved by adding 0.3% sub-micron Fe2O3 powder, the tensile strength, impact toughness and elongation of the alloy increase by 7.3%, 5.8% and 4.8%, respectively. For the high sinter activity of ultrafine iron particles reduced from the sub-micron Fe2O3 powder, the connection rate between the iron-based particles increases in the sintering process, the microstructure with more dimples is observed in the tensile fracture morphology, and the pore shape in the sintered body is apt to spheroidize.
出处
《粉末冶金材料科学与工程》
EI
北大核心
2015年第4期584-589,共6页
Materials Science and Engineering of Powder Metallurgy
基金
中南大学博士后科学基金资助项目
