含铝超高碳钢等温球化工艺的研究  

Isothermal spheroidization process of carbide in ultr-high carbon steel with addition of aluminium

作　　者：王宝奇[1] 宋晓艳[2] 李红娟[1] 张建军[1] 谷南驹[1] 

机构地区：[1]河北工业大学材料学院,天津300132 [2]北京工业大学材料学院,北京100022

出　　处：《材料科学与工艺》2004年第4期337-341,共5页Materials Science and Technology

基　　金：河北省教委博士基金资助项目(534003);河北省自然科学基金资助项目(500023).

摘　　要：在对超高碳钢进行铝合金化的基础上,利用成分不均匀奥氏体化加热控制,提出了锻态超高碳钢(UHCs-1 6Al)有效的无形变球化工艺,并利用扫描电镜对先共析碳化物的析出及球化进行了观察,分析了碳化物的球化机理.结果表明,通过对UHCs-1 6Al成分不均匀奥氏体化加热,使先共析碳化物在随后冷却时以粒状形式在基体上弥散析出,利用等温过程使其球化长大,并使奥氏体继续冷却时发生离异共析转变,从而获得球化组织;碳化物颗粒的尺寸可以通过等温温度和等温时间控制;当奥氏体化进行充分时,先共析碳化物析出的孕育期延长,部分碳化物在随后共析转变中以片状形式形成;UHCs-1 6Al最佳球化工艺的奥氏体化透烧温度和等温温度分别为850～870℃和780～800℃.The efficient and simplified isothermal spheroidizing process without deformation in the forged ultr-high carbon steel with addition of aluminium(UHCs-1.6Al) were proposed, which is characterized by austenitizing heating control and divorced eutectoid transformation. The spheroidizing mechanism of carbide was analyzed by means of SEM microstructure observation for the precipitation and growth of proeutectoid carbide. It is shown that the fine-spheroidized carbide precipitation dispersedly on matrix happened as cooling slowly from the austernite of inhomogeneous concentration, and the carbide precipitation was growed in spheroid during isothermal processs and the divorced eutectoid transformation happened during cooling after isothermal processs. The size of the spheroidized carbide was dependent on the temperature and time of isothermal process. The incubation period of proeutectoid carbide will extend when cooling from homogeneous austernite, and a part of the laminated carbide will form during eutectoid transformation followed by isothermal stage. The austenitizing and isothermal holding temperature ranges of the UHCs-1.6Aloptimizing spheroidizing process were 850～870 ℃ and 780～800 ℃ respectively.

关 键 词：球化 超高碳钢 奥氏体化 碳化物析出 析出 铝合金 孕育期 化工 工艺 片状 

分 类 号：TB333[一般工业技术—材料科学与工程] TG142[金属学及工艺—金属材料]