9Cr13轧辊钢淬火工艺研究

Study on Quenching Process of 9Cr13 Roll Steel

对高温加热后的9Cr13钢采用不同冷却介质进行淬火,随后均进行空冷,分析了不同冷却介质对高温加热后钢的表层组织、显微硬度以及心部韧性的影响。结果表明:不同冷却介质对9Cr13钢组织形貌、硬度及断口形貌有较大影响。当冷却介质为水时,表层组织中出现大量的片状马氏体,并出现脱碳现象,表层硬度最高,心部韧性较差,断口韧窝较少且出现大面积的较平区域;当冷却介质为10%盐水时,表层出现部分板条马氏体,硬度降低;冷却介质为机油时,表层组织出现大量细小的板条马氏体;当冷却介质为水-油双液时,表层组织中表现为大量的细小板条状马氏体,硬度分布均匀,且心部韧性较高,断口中出现大量小而深的韧窝。

9Cr13 steels after high temperature heating were quenched by using different cooling mediums, and then all were cooled in air. Effects of different cooling mediums on surface microstructure, micro-hardness and toughness of the core for the steels after high temperature heating were analyzed. The results show that different cooling mediums have great influence on the mierostructure, hardness and fracture morphology of 9Cr13 steel. When the cooling medium is water, there is a large number of plate martensite in the microstructure of surface layer. And decarburization phenomenon appears. The hardness on surface is the highest, the toughness at heart is poorer, the fracture toughness nest is less, and there is a large of flat area. When the cooling medium is 10% salt solution, some lath martensite is produced in surface layer, and the hardness reduces. When the cooling medium is engine oil, there is a larger number of small batten martensite in surface microstructure. When the cooling medium is water-oil two liquid, there is a large number of small batten martensite in surface microstructure, the hardness distribution is uniform, and the toughness of the heart is higher. There are a large number of small and deep dimples.