Preparation And Application Of Double Roll Crusher Wear-resistant Tooth Plate Material

Microstructures and mechanical properties of a new type tooth plate32CrMnSiNi2Mo cast steels have been studed by heat treatment test, optical microscope(OM), transmission electron microscope(TEM), scanning electron microscopy(SEM), tensile test, impact test and abrasive wear test.Experimental results show that AC1and AC3of32CrMnSiNi2Mo cast steel is730℃and820℃respectively and the microstructur normalized at different temperatures are new type bainite, composed of bainitic ferrite and remtained austenite. The hardness, tensile strengh, elongation and reduction of area first increase and then decrease with increasing of the normalizing temperature. While the impact toughness first descrease and then increase with the normalizing temperature. The optimizition heat treatment of normalizing at940℃and tempering at350℃has been determined. The hardness and the tensile strength first increase and than decrease with the tempering temperature, but impact toughness finally increases with the temperature. The influence of quenching temperature on the hardness, tensile strength and inpact toughness has the same tendency as the tempering temperature. The optimizition quenching at250-300℃,32CrMnSiNi2Mo cast steel has good strength and toughness and the tempering embrittlement occurs at350℃and500℃.The microstructure of32CrMnSiNi2Mo cast steel austenitiged at940℃is banitic ferrite and remarined austensite by air cooling, martensite, bainite territe and residual austenite by fog cooling, lath martensite and retained austenite by oil cooling and water cooling. It has good combined mechanical properies by air and fog cooling. After the pretreatment of680℃annealing. It has fine strength and toughness.The impact toughness is30J, and the hardness is43.4HRC of commercial tooth plate materials. The hardness hardly changes quenched at940℃and tempered below300℃, and gradually decreases with the temperature highter than300℃. The impact toughness gets to its minimun tempered at400℃.Disc wear test results show that the wear resistance of32CrMnSiNi2Mo cast steel normalized at940℃and tempered at low temperature is higher than that ot commercial tooth plate material. It has the best wear resistance tempered at200℃.When32CrMnSiNi2Mo cast steel compared with commercial tooth plate meterial, all of the wear surface hardness were higher at different levels then those before wear. Moreover the effect of working hardening of32CrMnSiNi2Mo is better than of the commercial tooth plate material.