Microstructure, Phases Transformation and Hardness of Sintered Fe-Mo-Si Alloys Prepared by Powder Metallurgy Technique

Abstract

Abstract The transition-metal silicides are attractive materials for high-temperature applications due to its mechanical properties and resistance to oxidation-corrosion at high temperature. In this paper, the development of silicides alloy based on ferromolybdenum (Fe-Mo) and ferrosilicon (Fe-Si) lumps as starting materials were discussed. The Fe-Mo and Fe-Si lumps were manually crushed into small granules. Afterwards, the small granule of Fe-Mo and Fe-Si were separately milled into fine powder and were then mixed by using Wet-High Energy Milling technique for 4h and 2h, respectively. The powders were compacted and then sintered at 1200°C for 2h in a vacuum. The microstructure of sintered alloys was observed by using SEM-EDX. Meanwhile, the formation of silicides phases was identified by using XRD. The Vickers hardness testing was performed to measure the hardness of sintered alloys. According to the results, the MoSi2 phase was detected in the (Fe-Si)-30(Fe-Mo) alloy. When the Fe-Si concentration was decreased to 40 % at, the FeMoSi phase was formed. The detail results of this study are presented and discussed in this paper.