TiC弥散强化灰铸铁汽缸套材料的组织及性能研究

Microstructure and Mechanical Properties of TiC Dispersion-Reinforced Grey Cast Iron for Cylinder Casing

采用添加含钛及碳粉末的预制块和添加Fe-Ti中间合金两种方法,制备了TiC颗粒弥散强化铸铁材料,并考察了强化铸铁的组织、力学性能和耐磨损性能。金相和XRD结果显示两种工艺均于基体中合成了呈小块状多边形的TiC颗粒,没有出现团聚现象。但通过添加粉末预制块合成的强化铸铁中同时出现了大量有害相莱氏体,且硬度也偏高。通过添加Fe-Ti中间合金合成的强化铸铁获得了较理想的组织,在油润滑条件下,其耐磨性能比基体合金提高大约1倍,该方法具有较好的工艺可行性。

TiC dispersion-reinforced cast iron was fabricated by adding preformed blocks containing Ti and C powder and Ti-Fe master alloy, respectively. The microstructure, mechanical properties and wear resistance of the strengthened cast iron were investigated. The results of metallographic analysis and XRD indicated that TiC particles can be synthesized in the matrix by both of the techniques, and the particles distributed uniformly. But a lot of ledeburite phase were found in strengthened cast iron fabricated by adding preformed blocks, and the hardness of the cast iron was too high. The cast iron made by adding Fe-Ti master alloy achieved ideal performance, and it shows high wear resistance under the lubricated condition. The synthesis technique of adding Ti-Fe master alloy had better feasibility.