Evaluating Mechanical Properties of Brazed Seal Joint of Planar Solid Oxide Fuel Cell by Small Punch Test

doi:10.3901/JME.2021.10.178

Abstract

Abstract: Obtaining the mechanical properties of the brazing seal of brazed joint is always a challenge. The elastoplastic mechanical properties of the whole sandwich structure of 304 stainless steel brazed joint of planar solid oxide fuel cell are obtained by small punch test, and the corresponding finite element model of the small punch specimen with the damage parameter of Gurson-Tvergaard-Needleman (GTN) is established. The method combining experimental and finite element analysis is used to obtain the yield strength, ultimate tensile strength and relevant damage parameters of the brazed joint, which are not able to be obtained by conventional testing methods. The validity of the finite element model is verified by the small punch tests of the brazed joints with different thickness brazing seam. Meanwhile, the fracture behavior of the 304 stainless steel brazed joint are investigated. The results show that the mechanical properties of the brazed joint are weaker than that of the parent metal. The increase of the thickness of the brazing seam will reduce the strength of the integrated brazed joint. The results of the present work are able to provide feasible methods and data for studying the strength of adaptive sealing structure of planar solid oxide fuel cell.

Key words: brazed joint, small punch test, GTN model, finite element analysis, fracture behavior

CLC Number:

TM911

SONG Ming, MA Shuai, JIANG Wenchun, DU Chuansheng, WANG Bingying. Evaluating Mechanical Properties of Brazed Seal Joint of Planar Solid Oxide Fuel Cell by Small Punch Test[J]. Journal of Mechanical Engineering, 2021, 57(10): 178-186.

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