Desgaste de aleaciones de hierro Cr-Mo-V-Ti para medios de molienda de minerales

Abstract

The effect of the chemical composition of carbide forming elements on the wear resistance of cast irons was evaluated by means of grinding balls. Four alloys for high chromium white iron grinding media with chromium content of 3.5 to 6.0% percent were melted in an induction furnace of 20 kg. It was performed in standard atmosphere and they were introduced into sand molds for producing metal ore grinding balls with a diameter of 51 mm. The alloys were subjected to dry attrition in an experimental test mill 200L×200ϕ mm. The alloy factors were: carbon alloy of 3.9 to 5.3%, molybdenum of 0.5 to 1.2%, vanadium and titanium of between 0.25 to 0.5%, manganese of 1.8 to 3.6%. It was shown their effects on the resistance wear in metallic ore conminution of silver, gold, zinc, iron and copper. The test metallic ore has large quantities of quartz up to 30%, making it difficult to be crushing and pulverizing. The purpose of these alloyings, were to produce "in situ" a large amount of massive cementite and hexagonal carbides of high chromium and titanium and vanadium refractory carbides. Alloys with a higher percentage of manganese, chromium and molybdenum, however, lower carbon percentage, had the best responses to the wear process. A composition 4C6Cr4MnMo0.5V0.5Ti obtained the best results.