热处理工艺对45#钢抗苜蓿草粉磨损性能的影响∗

摘要

Abrasive wear of alfalfa powder on the circular mould system is the main cause of the key parts failing on feed pellet machine.To improve the abrasive wear resistance of the key parts of circular mould system,the heat treatment of 45 steel was carried out by using different heat treatment process. The friction and wear behavior of 45 steel against alfalfa powder was studied on the abrasive wear test machine, the microstructure of the sample was analyzed by using metallo-graphic microscope,and the worn surface morphology was observed by using scanning electron microscope(SEM).The re-sults show that the abrasive wear of quenched 45 steel is dominated by micro-cutting wear and mechanical polishing,while plastic fatigue wear is not obvious.The wear resistance of 45 steel against alfalfa powder can be improved through rational matching of hardness and ductility when its hardness reaches certain value,meanwhile the subcritical quenching technique can obviously improve the wear resistance of 45 steel against plant abrasive compared with quenching.%苜蓿草粉对环模系统的磨粒磨损是造成饲料制粒机关键部件失效的主要原因。为提高环模系统关键部件材料的抗磨粒磨损性能,采用不同热处理工艺对45#钢热处理,在磨粒磨损试验机上考察其抗苜蓿草粉的磨损行为,用金相显微镜对试样的金相组织进行分析研究,用扫描电镜对试样摩擦表面的磨损形貌进行观察研究。结果表明：经淬火处理后45#钢的磨损主要表现为显微切削和机械抛光,未见明显的塑性疲劳；当材料的硬度提升至一定值时,通过硬度与韧度的合理配合可获得较好的抗植物磨料磨损性能；相对于常温淬火,45#钢亚温淬火后抗植物磨料磨损性能明显提升。