Probabilistic Model of Fracture Toughness for Pressure Vessel Steel 16MnR
Duan Quan, Cheng Guangxu,Jiang Peizheng
(Xi'an Jiaotong University , Xi'an 710049, China )

Abstract: Probabilistic characteristics of fracture toughness are studied for welded joint of 16MnR pressure vessel steel. The joint was divided into three independent zones, i.e. base material, weld metal and heat affect zone. The crack opening displacement $c of each zone were measured and the probability density functions were obtained. Gaussian distribution,log-normal distribution and Weibull distribution were taken into account. Using the K-S examination method, these three distributions were used to describe the scatter of $c. The Weibull distribution appears to be the best one.
Keywords: fracture toughness;probability density function;Weibull distribution