匀速冷却介质在18CrNiMo7-6齿坯锻后控冷中的应用  

Application of Uniform Cooling Medium in Controlled Cooling Process after Foring of 18CrNiMo7-6 Gear Blank

作　　者：牛文明 左永平 丁林 

机构地区：[1]南京科润工业介质股份有限公司,江苏南京211100

出　　处：《热处理技术与装备》2017年第3期60-64,共5页Heat Treatment Technology and Equipment

基　　金：科技型中小企业技术创新基金(13C26213202083)

摘　　要：18CrNiMo7-6齿坯锻后采用堆冷,易出现粒状贝氏体,硬度高,难以切削加工;经等温正火处理后,硬度得以降低,但粒状贝氏体不能有效消除,且带状组织级别较高,生产周期长,能耗大。18CrNiMo7-6齿坯锻后直接浸入一种新型匀速冷却介质中冷却,配合低温球化退火工艺,可获得以下优势:有效消除粒状贝氏体,改善了二次带状组织;得到细小、均匀分布的粒状珠光体组织(伪共析组织),组织均匀性提高;同时大幅度缩短生产周期,降低能耗。The 18CrNiMoT-6 gear blank in stacking cooling after forging appeared the defects such as granular bainite, high hardness and difficult machining. After isothermal normalizing, the hardness of gear blank decreased to the machining range, but the granular bainite could not be eliminated effectively, the level of banded structure was higher, the production period was long and the energy consumption was large. After forging, 18CrNiMo7-6 gear blank was directly dipped into a new uniform cooling medium cooling with low temperature spheroidizing annealing process. The results show that the controlled cooling process is effective to eliminate granular bainite, improve secondary banded structure, achieve the fine and uniform distribution granular pearlite structure （ pseudo eutectoid） and improve the microstructure uniformity. It also is greatly shorten the production cycle and reduced the energy consumption.

关 键 词：粒状贝氏体 等温退火 锻后控冷 匀速冷却介质 粒状珠光体 

分 类 号：TG142.1[一般工业技术—材料科学与工程] TG316.17[金属学及工艺—金属材料]