喷射成形新型热作模具钢的组织与力学性能研究  

Study on Microstructure and Mechanical Properties of New Type Spray Formed Hot Working Tool Steels

作　　者：张金祥[1] 欧阳希[1] 周健[1] 卓海鸥 张济山[2] ZHANG Jinxiang;OUYANG Xi;ZHOU Jian;ZHUO Haiou;ZHANG Jishan(Ganzhou Non-Ferrous Metallurgy Research Institute,Ganzhou 341000,China;State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]赣州有色冶金研究所,江西赣州341000 [2]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《热加工工艺》2018年第24期242-247,共6页Hot Working Technology

基　　金：国家重点基础研究发展计划(973)项目(2011CB606303)

摘　　要：对比了喷射成形新型热作模具钢与商用H13钢的性能差异,利用SEM和TEM进行微观组织分析,研究了合金元素对组织性能的作用规律。结果表明:喷射成形新型热作钢在韧性与H13钢相当的情况下,具有更高的回火抗性和高温强度。新合金在650℃回火时,组织仍然保持马氏体形态,在板条内发现了大量弥散细小的针状Mo2C,钉扎位错,推迟了马氏体的回复;而H13钢650℃回火组织中马氏体已经失去板条形态,位错密度大大降低,碳化物也明显聚集长大。仅仅降低钢中的Cr就可以明显提高新合金钢的回火抗性与高温强度,进一步增加Mo含量对高温强度影响较小,V含量的增加极大地增加了淬火后未溶碳化物的数量与尺寸,降低了固溶到基体的合金元素含量,反而降低了冲击韧性、回火抗性以及高温强度。The performance between new spray formed hot work die steel and commercial H13 steel was compared. The effects of alloying elements on microstructure and properties were studied by SEM and TEM. The results show that, the new spray formed hot working steel has higher tempering resistance and high temperature strength when its toughness is equal to that of H13 steel. After tempering at 650 ℃, the microstructure of the new alloy remained martensite, and a large number of dispersed and fine needle Mo2 C are found in the lath, which pins the dislocation and delays the recovery of martensite. The martensite of H13 steel at 650 ℃ tempering has lost its lath shape, the dislocation density has been greatly reduced, and the carbides have obviously accumulated and grown. The tempering resistance and high temperature strength of new alloy can be obviously improved by reducing the Cr content in the steel, and further increasing the content of Mo has little effect on the high temperature strength. The increase of V content greatly increases the quantity and size of undissolved carbides after quenching, and decreases the content of alloying elements dissolved to the matrix, and reduces the impact toughness,tempering resistance and high temperature strength.

关 键 词：喷射成形 H13钢 微观组织 力学性能 

分 类 号：TG156.6[金属学及工艺—热处理] TG142.45[金属学及工艺—金属学]