| Abstract Scope |
A group of TiB2-TiC based composite materials with fine microstructures and improved mechanical properties were developed for structural applications. First, a novel carbon coating precursor method was utilized to synthesis ultra-fine TiB2 and TiC powders with high purity. The synthesized powders were further used to process cermet materials with various metal additives such as Ni, Co, and high-entropy alloys. Due to the advantages of the fine particle size and high purity of the synthesized powders, the composite materials can be densified to high relative densities (>97%) at lower temperatures (lower up to 300°C). The materials also have very fine grain size (as fine as 1µm) and uniform microstructures (e.g. elongated grain structure due to the unique grain growth mechanism). Due to such microstructures, the materials have improved mechanical properties such as hardness, fracture toughness, and flexural strength. Hardening, toughening, and strengthening mechanisms were further discussed based on the microstructures. |