X. Dai, M. Maniruzzaman, R. D. Sisson, Worcester Polytechnic Institute, Worcester, MA
The effects of quench starting temperature on the cooling rates and therefore the resulting calculated heat transfer coefficients have been experimentally determined using several quench probes. The results show that the cooling rates and therefore heat transfer coefficients increase with increases in the quench starting temperature. The results also indicate that the heat transfer coefficient at any temperature is a function of the quench starting temperature. These results are discussed in terms total heat content of the probe and the fluxes as a function of time and temperature.
Summary: To model the phase transformations, residual stresses and distortion that occur during quenching, you must know the boundary conditions in terms of the heat transfer coefficient as a function of the part surface temperature; h(T). The h(T) is a function of the quenching fluid and its velocity as well as part geometry, orientation and surface condition. This work has determined that the h(T) is also a function of the solutionizing or Austenitizing temperature (quench start temperature). The experimental results are presented and discussed in terms of total heat content and fluxes.
