Wisconsin Alumni Research Foundation

Mark K Hoffmeyer

John Harry Perepezko

The Droplet Emulsion Technique is used to produce droplets of bulk metal or metal alloys containing inoculant particles. Heterogeneous nucleation responses are then separated and identified with variances in inoculant chemistry, size, morphology, and surface conditions in the different droplets. Differential Thermal Analysis (DTA) is used to detect and to correlate thermal signals generated from as little as 50 droplets 75-100 .mu.m in size, allowing the separation of signals generated by a minor fraction of the total droplet population. Quenching treatments are used on the samples during thermal analysis to retain the original solidification microstructures produced from effective inoculation. Differences between droplet solidification microstructures preserved from the quenching treatments allow for visual identification of effective and ineffective inoculant particles. The factors controlling effective inoculation of solid include the chemistry, morphology, crystal structure, and surface conditions of inoculant particles which are identified by using analytical x-ray and electron microbeam techniques.

Growing community of inventors

Madison, WI, United States of America

Mark K Hoffmeyer