Abstract��20MnTiB high strength bolt was fractured after 24 hours service. The analysis on optical microscopr, SEM, EDAX, hardometer and chemincal composition were carried out on the cracked bolt. The comprehensive analysis results showed that the bolt existed cracks before using.The primary cracks led to stress concentration,so the hydrogen in material moved to the crack top and enriched. With local incerease in hydrogen content there occured hydrogen ductile��brittle fracture in bolt.
����;������. ��ǿ����˨����ʧЧ����[J]. �й������ڿ���, 2008, 26(2): 50-0.
WANG Rong;SUN Ming��zheng. Fracture Analysis of High Strength Bolt. Chinese Journal of Iron and Steel, 2008, 26(2): 50-0.
2008, Vol. 26 
