摘要
利用恒位移加载台，在TEM中原位观察了Fe3Al薄膜试样充氢和应力腐蚀前后裂尖位错组态的变化，以及位错对裂纹形核的影响．结果表明，氢能促进裂尖发射位错，促进位错的增殖和运动，并使无位错区增大．当位错发射、运动发展到临界状态时，就会导致氢致裂纹的形核与扩展．对氢促进位错发射。
The change of dislocation configuration ahead of a loaded crack tip before and after charging with hydrogen, and stress corrosion cracking, and relationship between dislocation and initiation of hydrogen-induced cracking (HIC) for Fe3Al are investigated in TEM using a special constant deflection loading device. The results show that hydrogen can enhance dislocation emission, multiplication and motion, and increase the size of dislocation free zone (DFZ). A nanocrack of HIC will initiate and Dropagae in the DFZ when hydrogen enhanced dislocation emission and motion reach a critical condition. The reasons that hydrogen enhanced dislocation emission and motion, and the mechanism of initiation of HIC have been discussed.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
1997年第7期709-717,共9页
Acta Metallurgica Sinica
基金
国家自然科学基金!19392300-6!!59591913
关键词
FE3AL
氢致开裂
应力腐蚀
TEM
Fe3Al, hydrogen-enhanced dislocation emission, hydrogen-induced crackIng
