TiAl合金铸造缺陷研究进展OA

The titanium aluminide(TiAl)alloys,endowed with low density,high specific strength,and excellent high-temperature properties,are ideal candidate materials for the low-pressure turbine blades in aero-engines.However,their high melting point and poor melt fluidity often result in casting defects such as the shrinkage cavity,shrinkage porosity,gas hole,segregation,and crack during casting process,which significantly degrade the tensile,fatigue,and high-temperature creep properties of the alloys.This paper reviews the characteristics and development history of TiAl alloys,with a focus on the influence of casting processes on the casting defects and mechanical properties,as well as the post-casting treatment technologies.The research results indicate that the casting process optimization and post-treatment technologies can effectively minimize the defects and enhance the mechanical performance of TiAl alloys.Finally,it is pointed out that the engineering application of cast TiAl alloys still faces significant challenges.Future efforts should focus on deepening the understanding of defect formation mechanisms and control methods,developing intelligent casting and post-processing technologies,and perfecting non-destructive testing and quality evaluation systems to achieve the integration of"alloy composition-casting process-defect control-microstructure and properties",thereby promoting the engineering application.