US 9,810,615 B2  
Calibration method for the brittle fracture assessment parameters for materials based on the Beremin model  
Fuzhen Xuan, Shanghai (CN); Yupeng Cao, Shanghai (CN); Hu Hui, Shanghai (CN); Penning Li, Shanghai (CN); and Guozhen Wang, Shanghai (CN)  
Assigned to East China University of Science and Technology, Shanghai (CN)  
Appl. No. 14/365,273 

Filed by East China University of Science and Technology, Shanghai (CN)  
PCT Filed Nov. 27, 2012, PCT No. PCT/CN2012/085336 § 371(c)(1), (2) Date Jun. 13, 2014, PCT Pub. No. WO2013/086933, PCT Pub. Date Jun. 20, 2013. 

Claims priority of application No. 2011 1 0415419 (CN), filed on Dec. 13, 2011.  
Prior Publication US 2014/0372060 A1, Dec. 18, 2014  
Int. Cl. G06F 11/30 (2006.01); G01N 3/62 (2006.01); G01N 3/40 (2006.01); G06F 17/50 (2006.01) 
CPC G01N 3/62 (2013.01) [G01N 3/40 (2013.01); G06F 17/5018 (2013.01); G01N 2203/0067 (2013.01); G01N 2203/021 (2013.01); G01N 2203/0218 (2013.01)]  10 Claims 
1. A calibration method for the brittle fracture assessment parameters for materials based on the Beremin model, the method
comprises the following steps:
(1) Selecting at least two types of specimens made of a same material but with different constraints, and calculating the
fracture toughness value K_{0 }corresponding to 63.2% failure probability for each type of specimens at a same calibration temperature by using the respective
fracture toughness data;
(2) Constructing finite element models for each type of specimens using the stressstrain curve of the material measured at
the same calibration temperature, and calculating the maximum principal stress σ_{1,i }and element volume Vi of each element at K=K_{0 }in each model, where K is a stress intensity factor that describes the intensity of far field loading on the crack front,
and i is an order number of elements;
(3) Assuming a series of values of the Weibull slope m and calculating a set of values of the Weibull scale parameter σ_{u }for each type of specimens according to the following equation, and plotting the Beremin's parameters characteristic curves
for each type of specimens with the curves representing the relationship between m and σ_{u }for each type of specimens;
(4) Determining the brittle fracture assessment parameters for the material according to the coordinates of the intersection
of the Beremin's parameters characteristic curves;
(5) using the brittle fracture assessment parameters in safety engineering.
