Microstructure and Wear Resistance of Hard-facing Weld Metal on JIS-S50C Carbon Steel Surface

Abstract

JIS-S50C medium carbon steel was important raw metal that used for producing the agricultural machine part because of an excellent mechanical properties and low cost. When these parts were applied and failed during the service, the parts were frequently repaired using a welding repair technique with a random selection of welding process parameter. In the present day, it was found that the selection of the optimized welding process parameter for specific part and metal was still concerned and investigated. This research aimed to study an influence of pre-heat temperature and inter-pass temperature on JIS-S50C medium carbon steel hard-facing weld metal properties.  The summarized experimental results showed that decreasing of pre-heat temperature and the inter-pass temperature affected to decrease the grain size, increase the hardness and also increase the wear resistance of the hard-facing weld metal. The optimized pre-heat temperature and inter-pass temperature that produced the weld metal hardness of 984 HV and minimum wear rate of 2.02 g was the pre-heat temperature and the inter-pass temperature of 150^oC. Increase of hard-facing layer also affected to decrease the wear rate due to the decrease of the grain size and the increase of the weld metal hardness.