MICROSTRUCTURE AND MECHANICAL BEHAVIOR OF LIQUID METAL COOLED DIRECTIONALLY SOLIDIFIED GTD-444

摘要

Extensive R&D of high gradient casting processes has shown that liquid metal cooled (LMC) directional solidification (DS) is one of the most promising technologies for the production of high quality, high performance investment castings. In the present study, the microstructures of LMC and conventional radiation cooled (RC) DS GTD-444 castings were compared. Microstructural features such as dendrite arm spacing, phase segregation, carbides, and gamma prime morphology were analyzed. The effect of the microstructure on low-cycle fatigue behavior was also examined.