Options
Fracture Toughness of Nafion-212 Polymer Electrolyte Membrane
Journal
Lecture Notes in Mechanical Engineering
ISSN
21954356
Date Issued
2022-01-01
Author(s)
Pilla, Kartheek
Tanwar, Akash
Jonnalagadda, Krishna N.
Abstract
Polymer electrolyte membrane-based (PEM) fuel cells have numerous advantages over conventional power generation sources owing to their low operating noise, higher efficiency (compared to diesel or gas engines), and negligible pollution. These favourable factors have contributed to the demand for PEM-based fuel cells. PEM membrane is a crucial component of a fuel cell, whose reliability limits the life of the fuel cell. Formation of pinholes/cracks results in fuel crossover, which can lead to catastrophic failure of fuel cell/stack. Therefore, it is important to understand the fracture toughness of the PEM membranes. In the present work, the fracture toughness of the most widely used PEM membrane, Nafion-212, was investigated at room temperature under in situ tensile loading condition. Essential work of fracture (EWF) method on DDENT (deeply double-edge notch tension) and SENT (single-edge notch tension) specimens were employed to calculate the fracture toughness of Nafion-212 thin films. The Digital image correlation (DIC) technique was employed for validation of EWF as well as for computation of J-integral. The equivalence between EWF and J-integral calculation methods was established. It was observed that the crack tip root radius had a significant effect on the essential work of fracture. For laser-cut DDENT specimens with blunt crack, the EWF was 6.9 kJm-2, whereas the razor blade-cut DDENT specimens with sharp crack tip have an EWF of 0.93 kJm-2.
Subjects