TY - GEN
T1 - Application of direct current potential drop for the J-Integral vs. Crack Growth resistance curve characterization
AU - Chen, Xiang
AU - Nanstad, Randy K.
AU - Sokolov, Mikhail A.
N1 - Publisher Copyright:
© Copyright 2014 by ASTM International.
PY - 2015
Y1 - 2015
N2 - The dc potential drop (DCPD) technique has been applied to derive the J-integral versus crack growth resistance curve (J-R curve) for fracture toughness characterization of structural materials. The test matrix covered three materials including type 316LN stainless steels, Ni-based alloy 617, and one ferritic-martensitic steel, three specimen configurations including standard compact, single edge bend, and disk-shaped compact specimens, and temperatures ranging from 20 to 650°C. When compared with baseline J-R curves derived from the ASTM E1820-13 normalization method, the original J-R curves from the DCPD technique yielded much smaller JQ values due to the influence of crack blunting, plastic deformation, etc., on potential drop. To compensate these effects, a new procedure for adjusting DCPD J-R curves was proposed. After applying the new adjustment procedure, the average difference in JQ between the DCPD technique and the normalization method was only 5.2 % and the difference in tearing modulus was 7.4 %. These promising results demonstrate the applicability of the DCPD technique for J-R curve characterization especially in extreme environments, such as elevated temperatures, where the conventional elastic unloading compliance method faces considerable challenges.
AB - The dc potential drop (DCPD) technique has been applied to derive the J-integral versus crack growth resistance curve (J-R curve) for fracture toughness characterization of structural materials. The test matrix covered three materials including type 316LN stainless steels, Ni-based alloy 617, and one ferritic-martensitic steel, three specimen configurations including standard compact, single edge bend, and disk-shaped compact specimens, and temperatures ranging from 20 to 650°C. When compared with baseline J-R curves derived from the ASTM E1820-13 normalization method, the original J-R curves from the DCPD technique yielded much smaller JQ values due to the influence of crack blunting, plastic deformation, etc., on potential drop. To compensate these effects, a new procedure for adjusting DCPD J-R curves was proposed. After applying the new adjustment procedure, the average difference in JQ between the DCPD technique and the normalization method was only 5.2 % and the difference in tearing modulus was 7.4 %. These promising results demonstrate the applicability of the DCPD technique for J-R curve characterization especially in extreme environments, such as elevated temperatures, where the conventional elastic unloading compliance method faces considerable challenges.
KW - DCPD
KW - J-R curve testing
KW - Normalization method
UR - http://www.scopus.com/inward/record.url?scp=84975047652&partnerID=8YFLogxK
U2 - 10.1520/STP158420140057
DO - 10.1520/STP158420140057
M3 - Conference contribution
AN - SCOPUS:84975047652
T3 - ASTM Special Technical Publication
SP - 97
EP - 112
BT - Evaluation of Existing and New Sensor Technologies for Fatigue, Fracture and Mechanical Testing
A2 - Kang, Jidong
A2 - Dudzinski, David
A2 - Jablonski, David
PB - ASTM International
T2 - 4th Symposium on the Evaluation of Existing and New Sensor Technologies for Fatigue, Fracture and Mechanical Testing
Y2 - 7 May 2014 through 8 May 2014
ER -