Analysis of Pop-In Phenomenon in the Process of Ceramic Materials Instrumented Indentation

Based on the finite element analysis method, the relationship between two systems of crack (radial crack and lateral crack) and pop-in phenomenon were compared during the instrumented indentation process in ceramic materials. In order to give a reasonable explanation for mechanism analysis of pop-in phenomenon in the process of ceramic materials instrumented indentation, this paper proposed the viewpoint that pop-in phenomenon is caused by the lateral crack in the process of ceramic materials instrumented indentation. This work provided a theoretical basis for the study of instrumented indentation methodologies based on the pop-in phenomenon to determining mechanical properties of ceramic materials.

Failure Analysis on Lifted Ball Bond and Micro Lateral Crack Using Fractography Approach

This paper demonstrates the application of fractography on ductile fracture in gold wire bonding and brittle fracture in micro lateral crack of silicon chip. Different separation mode of a lifted wire ball was mapped through the study of various sizes of dimples, ductile zone and non-welded area. Multiple Focus Ion Beam (FIB) cuts were required at lateral crack area in order to expose the horizontal fracture features to determine the crack propagation direction.

Research on Effects of Pressure Loading on Rock Lateral Cracks Occurrence under Confining Pressure

Numerical simulations of effects of confining pressure on occurrence of rock lateral cracks were performed by using the numerical analysis software. The results indicate that the rock tends to have median cracks with the increasing of penetration under no confining pressure, while the rock tends to have lateral cracks with the increasing of penetration under confining pressure. The relative position of lateral crack initiation is dependent on the confining pressure when loading, which is independent of the penetration. The greater the confining pressure, the closer the lateral crack location to the rock surface. With the increasing of penetration and confining pressure, the lateral crack direction is towards to the direction parallel to the rock surface.

Numerical Simulation of Pressure Loading Effects on Occurrence of Rock Lateral Cracks under Confining Pressure

Numerical simulations of pressure loading effects on occurrence of rock lateral cracks under confining pressure were performed by using the numerical analysis software. The results indicate that the rock tends to have median cracks with the increasing of penetration under no confining pressure, while the rock tends to have lateral cracks with the increasing of penetration under confining pressure. The relative position of lateral crack initiation is dependent on the confining pressure when loading, which is independent of the penetration. The greater the confining pressure, the closer the lateral crack location to the rock surface. With the increasing of penetration and confining pressure while loading, the lateral crack direction is towards to the direction parallel to the rock surface.