Microstructure and fracture mechanism of Cu-Y2O3 composite

Abstract

This work aimed to examine the structure of Cu-Y2O3 composite, analyse the fracture mechanism, and propose the model of fracture. The in-situ tensile test in SEM was used for direct observation of the process of deformation and fracture. Microscopic analysis revealed that Cu matrix grains are spherical with a mean diameter of ∼ 500 nm. EDX and selected area electron diffraction confirmed the presence of Y2O3 particles. Particles can be divided, according to the size, into two categories: smaller A (up to 20 nm) and more significant B (20-100 nm). The in-situ tensile test in SEM showed that the first cracks were created on the particle-matrix interfaces and in the triple point. Subsequent coalescence was observed, and we assumed that the cracks propagate along the grain boundaries. The fracture surface has a transcrystalline ductile character. Based on the in-situ observations and analysis, we proposed the model of fracture mechanism.

Supported by 2D and 3D Imaging Methods Investigation of the Influence of Fiber Orientation on the Mechanical Properties of the Composites Reinforced with Fibers in a Polymer Matrix

“…Tensile tests are conducted on purpose to determine values of strength and modulus [4,18], which will be used to determine the necessary technology to make a product with the desired properties for the environment in which the product will work. The examination of cracks initiation and their propagation may translate into an improvement in the mechanical properties of the created composites [19,20].…”