A test method to measure shear strength of ceramic joints at high temperatures

Abstract

The asymmetrical four-point bend (AFPB) method, which provides a pure shear stress state in the middle of the test specimen, was utilized to measure the shear strength of the joints between Nicalon-fiber-reinforced SiC composites. The small test specimens were prepared as butt-joints with uniform depth (no notch). It was shown experimentally that the position of loading points is critical to induce shear fracture at the joint without the failure of base material. The appropriate positions for the present test specimen were determined and, as a result, an articulated ceramic fixture was designed. This test method is economical and involves small test specimens with simple geometry, and can be used at high temperatures.