Abstract��Analysis of the surface spalling of back��up roll Cr5 was carried out using optical microscope, ultrasonic probing and mechanical property testing. The macroscopical fracture analysis and probing results show that the roll underwent a fatigue extending process. The crack began at the bottom of the hardening layer, followed the roll��s circumference, and reversed its rolling direction. The fragment fell from the roll is the hardening layer, and the micrograph of its surface, its middle area and its bottom are martensite, sorbite, and troostite respectively. The reasons of the failure are the manufacturing defect in the wok side of the roll, as well as its improper heat treatment process.
��ѧΰ;���»�;����Ƽ;�º���. Cr5֧�й�ʧЧ����[J]. �й������ڿ���, 2007, 25(4): 55-0.
LIU Xue��wei;PEI Xin��Hua;ZHOU Li��ping;MU Hai��ling. Cracking Failure Analysis of Back��up Roll of Cr5. Chinese Journal of Iron and Steel, 2007, 25(4): 55-0.
2007, Vol. 25 
