Semi-solid Forming Of High Chromium Cast Iron

Semi-Solid Metal Process has actively been spread all around the world in recent years. Up to now Semi-Solid Metal Process has been developed for more than 30 years, it is called by experts as a new generation of metal formation technique in 21 century for the presence of a lot of advantages. Among many studies, the materials researched concentrate on nonferrous alloys. However, the alloys with high molting point especially Fe-base alloy, which had not much study in producing SSM. The methods of fabricating non-dendritic microstructure are confined to stirring and special pretreatment(pr post-treatment). In view of this situation, the hypo-eutectic Fe-Cr-C white cast iron,the hyper-eutectic Fe-Cr-C white cast iron with high melting point was choosen as a semi-solid alloy. A new method to form non-dendritic microstructure was used to fabricate semi-solid Fe-base alloy bellets.Looking for a good way which is simple, dependable and economical to produce semi-solid blocks is the experimental goal.In the experiment for the hypo-eutectic, non-dendretic microstructures were obtained by a cooling plate proessing technique. And the non-dendretic microstructures were characterized by equivalent diameter and shape factor. The best processing conditions to form ideal primary austenite were concouded. The temperature is 50 C above the liquidus is the best processing condition, average shape factor of primary austenite obtained is 0.792, average equivalent diameter is 40.7um. Abrasion resistance of hypo-eutectic high chromium white iron by normal casting and hypo-eutectic high chromium white iron by Semi-solid state forming has been investigated in this paper by means of impact abrasion test. The results show that the abrasion resistance of hypoeutectic high chromium white iron by Semi-solid state forming is higher than that of hypoeutectic high chromium white iron by normal casting.In the experiment for the hyper-eutectic, primary carbide phase was thinned by a cooling plate proessing technique. And the thinedmicrostructures were characterized by amount and volume fraction of carbide phase in different area. The best processing conditions to form ideal thinned Carbide phase were concouded. The temperature is 50C above the liquidus is the best processing condition., Abrasion, resistance of hyper-eutectic high chromium white iron by normal casting and hypoeutectic high chromium white iron by Semi-solid state forming has been investigated in this paper by means of impact abrasion test. The results show that the abrasion resistance of hyper-eutectic high chromium white iron by Semi-solid state forming is higher than that of hypoeutectic high chromium white iron by normal casting.In a word, To make semi-solid blocks by a cooling plate proessing technique, it has some advantages such as short technological process , easy-to-move , and the stable processing course and suit to industrilize. The method and metals field of the study Semi-solid state forming is expanded. It must lay a good theoretical and experimental foundation on studying ferro-based alloys by a cooling plate proessing technique. All of those must speed up industry application steps on direct formation technique of SSM.