Session: MF-02-04 Materials for Hydrogen Service (Joint with C&S)-4

Paper Number: 154762

154762 - Effect of the Hydrogen Charging Method on the Mechanical Behavior of 304 Stainless Steels 

Abstract: 

304 stainless steels have been widely used in pressure vessels and piping due to its combination of machinability, weldability and corrosion resistance. Nevertheless, 304 stainless steels are known to be susceptible to hydrogen embrittlement when employed in hydrogen facing applications. The underlying mechanisms of hydrogen embrittlement in 304 stainless steel have not been fully understood, especially under fatigue loading conditions. In order to understand the effects of hydrogen on stainless steels both electrochemical charging and gas charging have been used. In the present study, we systematically examine the effect of the charging method, i.e., electrochemical charging vs. gas charging, on the mechanical response, i.e., tensile, fatigue and nano-indentation response, of the hydrogen charged materials. It is demonstrated that the method of charging has a pronounced effect on the effective yield strength and strain to failure of hydrogen charged materials. Microstructural assessment subsequent to tensile testing of hydrogen charged materials highlights the emergence of unusual and numerous surface cracks which also depend on the nature of the hydrogen charging method as well. The observed differences in the mechanical response of hydrogen charged materials are attributed to the differences in the amount of hydrogen and the distribution of hydrogen obtained in the two charging methods. The insights obtained in this study have the potential to offer valuable guidance on understanding hydrogen effects in materials exposed to a different service conditions.

Presenting Author: T VENKATESH STONY BROOK UNIVERSITY

Presenting Author Biography: Dr. T. A. Venkatesh is currently an Associate Professor in the Materials Science and Chemical Engineering department at Stony Brook University, New York. He received his doctoral degree in Materials Science and Engineering at the Massachusetts Institute of Technology, Cambridge, MA, USA. Through modeling and experimental approaches, his research group is focused on understanding material behavior such as mechanical strength, fracture, fatigue and high temperature response of structural materials and multi-functional behavior of smart materials, with applications in clean energy, sensors and biomedical systems. He is the recipient of the US National Science Foundation’s Early Career Award. He is also the principal investigator, leading a multi-disciplinary University-National Laboratory-Industry effort, with MIT and Stanford, in developing advanced materials for the hydrogen economy. He has published over 70 papers and his publications have received over 4000 citations.

Authors:

Cheng-Yuan Tsai MIT
Ting Yang MIT
Wurong Jian Stanford University
Yamini Mann Stony Brook University
Joeseph Ronevich Sandia National Laboratory
Chris San Marchi Sandia National Laboratory
Wei Cai Stanford University
T VENKATESH STONY BROOK UNIVERSITY
Ming Dao MIT