J. S. Keist, Arizotah, LLC, Plymouth, MN; D. L. Dingmann, C. H. Bergman, Technomics, LLC, Plymouth, MN

Summary: In fluidized bed quenching, a vapor barrier does not form around the part allowing one the ability to control residual stresses and part distortion. The fluidized bed consists of a fine hard media that is fluidized by a gas. As a part is immersed into the fluidized bed, the fluidized bed media directly contacts the part resulting in consistent and even cooling. Fluidized bed quenching was compared to traditional water quenching. Analysis was made on residual stresses, part warpage, and mechanical properties of 300 series aluminum alloy castings. Parts quenched in the fluidized bed exhibited minimal temperature gradients significantly reducing residual stresses and reducing part distortion. Fluidized bed quenching is an attractive alternative for parts exhibiting high surface to weight ratios where one requires low residual stresses and minimal part distortion.