摘要
研究了Ni-Cr-Mo-B超厚钢板表面低碳回火马氏体组织.对表面区域不同位置处取样进行了冲击性能测试,并借助OM,SEM,EBSD,XRD和正电子湮没谱(PAS)等技术手段对马氏体组织及其亚结构进行了研究.结果表明,实验钢表面韧性异常恶化,马氏体组织中相对粗大的板条束和板条块以及较高的位错密度是其表面韧性恶化的主要原因.
Low carbon tempered martensite structures in the surface of Ni-Cr-Mo-B ultra-heavy plate steel was studied.The toughness at different locations in the surface zone was investigated by impact testing,and the sub-microstructures,such as packets and blocks of the martensite,at different distances（3,15 and 25 mm） from the surface were observed by OM,SEM and electron backscattered diffraction（EBSD）,and the dislocation density were tested by XRD and positron annihilation spectroscopy（PAS）.The results indicate that the toughness of the tested steel in the 10 mm from the surface deteriorates sharply,which is mainly due to the bigger packet and block size and higher dislocation density in the tempered martensite.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第4期401-406,共6页
Acta Metallurgica Sinica
关键词
超厚板
EBSD
正电子湮没谱
位错密度
ultra-heavy plate steel
EBSD
positron annihilation spectroscopy（PAS）
dislocation density
