Two kinds of water atomized pre-alloyed powders with high Si content were used as raw materials. The sintering temperature range was determined by DSC analysis. High chromium cast iron with high mechanical properties were prepared by super-solidus liquid phase sintering (SLPS). Optical microscopy and scanning electron microscopy were used to analyze the microstructure changes of high chromium cast iron, and the performance of two-component sintered high chromium cast iron was compared and analyzed. The results show that the alloys with similar composition, the alloy containing 1.48% of Si is hypoeutectic, and the alloy containing 3.23% of Si is a typical hypereutectic composition. Both carbides are short rods, evenly distributed at the grain boundary and the subgrain boundary. At the same time, Si atoms can be dissolved in austenite, which reduces the solubility of C and Cr atoms in austenite, which in turn affects the austenite stability. Finally, the two alloys get different matrix structures. Compared with the alloy containing 1.48% of Si, the mechanical properties of the alloy containing 3.23% of Si decreased. The hardness of the alloy containing 1.48% of Si is HRC56.5, the impact toughness is 9.59J/cm2, the bending strength is 2208.98MPa. The hardness of the alloy containing 3.23% of Si is HRC48.5, the impact toughness is 2.73J/2 ancmd the bending strength is 1664.28 MPa.
基金资助:国家自然科学基金(51574119)。
作者简介: 石管华:硕士研究生,研究方向为粉末冶金新材料与新成形工艺。
引用本文:
石管华,肖平安,顾景洪,李忠涛,肖利洋. 硅对烧结态高铬铸铁组织与性能的影响研究[J]. 航空制造技术, 2019, 62(22): 52-57.
SHI Guanhua, XIAO Pingan, GU Jinghong, LI Zhongtao, XIAO Liyang. Effect of Silicon on Microstructure and Properties of Sintered High Chromium Cast Iron. Aeronautical Manufacturing Technology, 2019, 62(22): 52-57.