Directional Growth of Eutectic Composite by Fluidized Bed Quenching
Transactions of the Iron and Steel Institute of Japan
A laboratory evaluation of a new directional solidification method by means of fluidi zed bed quenching (FBQ ) was made in comparison with the high rate solidification (lIRS) and the liquid metal cooling (LMC) methods. T his efficient technique provides significantly improved process parameters over currently commercialized HRS because, for example, the attainable thermal gradient exceeds 200°C/cm, indicating an approximate£v equivalent cooling capability to that of L MC which requires absolute
... h requires absolute avoidance of liquid metal contact with the cast body as well as relatively sophisticated procedures and facilities for the coolant temperature control . Together with these conditions in mind, the FBQ method is considered to be a highly prospective technique fo r the economical directional solidification process. T he FBQ method was apJllied to in-situ growth of rlr'-Mo eutectic composites as a base metal for a potential candidate if a gas turbine blade in the next decade. The paper describes the microstructure and the grown-in difects in the composites which consists of rlr' matrix and body celltered cubic jibers primarily if Mo .