TY - GEN
T1 - Temperature rise near a crack tip due to plastic work under intermediate loading rate and the study of loading rate dependency on fracture toughness for steels
AU - Toyosada, Masahiro
AU - Gotoh, Koji
AU - Sagara, Kenji
PY - 1992
Y1 - 1992
N2 - This paper investigates temperature rise distribution near a crack tip of CT specimens of a mild steel due to plastic work under intermediate loading rate for the purpose of considering the criterion for crack instability under arbitrary loading rate. The dynamic thermal elastoplastic FEM analysis shows good agreement with experimental temperature rise distributions by using a thermo viewer. The calculation results of yield stress in the process zone in the vicinity of a crack tip is fairly constant because of opposed effects of strain rate and temperature on yield stress. Moreover yield stress in the process zone increases with increasing loading rates up to a certain rate due to the increase in strain rate, however, the increase in loading rates over the certain value leads to decrease in yield stress which is caused by local heating near a crack tip due to plastic work because there is not enough time to dissipate heat. From the above information, the criterion of fracture initiation under arbitrary loading rate is conducted. Experimental Kc values of HT-50 TMCP steel with various loading rates support quantitatively the criteria.
AB - This paper investigates temperature rise distribution near a crack tip of CT specimens of a mild steel due to plastic work under intermediate loading rate for the purpose of considering the criterion for crack instability under arbitrary loading rate. The dynamic thermal elastoplastic FEM analysis shows good agreement with experimental temperature rise distributions by using a thermo viewer. The calculation results of yield stress in the process zone in the vicinity of a crack tip is fairly constant because of opposed effects of strain rate and temperature on yield stress. Moreover yield stress in the process zone increases with increasing loading rates up to a certain rate due to the increase in strain rate, however, the increase in loading rates over the certain value leads to decrease in yield stress which is caused by local heating near a crack tip due to plastic work because there is not enough time to dissipate heat. From the above information, the criterion of fracture initiation under arbitrary loading rate is conducted. Experimental Kc values of HT-50 TMCP steel with various loading rates support quantitatively the criteria.
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M3 - Conference contribution
AN - SCOPUS:0026622692
SN - 1880653044
T3 - Proc Second Int Offshore Polar Eng Conf
SP - 108
EP - 115
BT - Proc Second Int Offshore Polar Eng Conf
PB - Publ by Int Soc of Offshore and Polar Engineerns (ISOPE)
T2 - Proceedings of the Second International Offshore and Polar Engineering Conference
Y2 - 14 June 1992 through 19 June 1992
ER -