Improved Synchronous Characterization Theory for Surface and Interface Mechanical Properties of Thin-Film/Substrate Systems: A Theoretical Study on Shaft-Loaded Blister Test Technique

Materials (Basel). 2024 Oct 16;17(20):5054. doi: 10.3390/ma17205054.

Abstract

In this paper, the previously proposed shaft-loaded blister test technique for the synchronous characterization of the surface and interface mechanical properties of a thin-film/substrate system is further studied theoretically. The large deflection problem of the steady shaft-loaded blistering thin film is reformulated by surrendering the small-rotation-angle assumption of the membrane, which was previously adopted in the out-of-plane and in-plane equilibrium and radial geometric equations. A new and more accurate analytical solution to this large deflection problem is presented and is used to improve the previously presented synchronous characterization theory. The new analytical solution is numerically compared with the previous analytical solution to confirm the superiority of the new analytical solution over the previous analytical solution. An experiment is conducted to verify the beneficial effect of the improved synchronous characterization theory on improving the characterization accuracy.

Keywords: analytical solution; large deflection; shaft-loaded blister test; synchronous characterization; thin-film/substrate delamination; thin-film/substrate system.