부산대학교 도서관

In this study, microscratch test was combined with fracture-mechanical analysis to characterize the interfacial adhesion of catalyst coating on electrolyte polymer in a direct methanol fuel cell (DMFC). Scratch test was used to determine the critical load for interfacial failure, while fracture-mechanical analysis was used to quantify the adhesion between Nafion (the electrolyte polymer substrate) and Pt-Ru alloy (catalyst coating). Especially, it is appropriate to establish a relationship between interfacial toughness and adhesion failure by scratching because the failure mechanism by electrochemically induced swelling and shrinking at this interface is very similar to that of scratch testing. We also proposed a key of solving ambiguous problems in indentation cracking test by determining geometric information from crack propagation and critical points, as for a hard porous coating on a soft substrate. Finally, three kinds of process manufacturing catalyst layer for anode were compared to verify our new test algorithm qualitatively.