TiAl-계 감마(γ)합금의 입자조직 제어와 그 응용

초록

Gamma titanium aluminides (TiAl-base) are emerging as a potential candidate structural materials for high temperature, light-weight applications. Among the many variables, the nature of the microstructural components and distribution characteristics of phases are of utmost importance with affect the mechanical properties, particularly room temperature tensile ductility, fracture toughness and fatigue resistance. Chemical compositions, heat treatments and advanced synthesizing technique such as EPM have been developed such that a favorable lamellar colony structure is obtained. Alloying additions improve the mechanical properties of TixAly via their fundamental roles on deformation behaviors. Although much remains to be clarified, a coherent view on the crystallographic characteristics of the lamellar structure with respect to their hardening roles on slip and twinning transfer is being formed. Basic studies as well as applied research trends in the last decade are reviewed to shed a light in the future efforts.