New closed cell composite metal foam has been processed using both casting and powder metallurgy (PM) techniques. The foam is comprised of steel hollow spheres packed into a dense arrangement, with the interstitial spaces between spheres occupied with a solid metal matrix. Using the casting technique, an aluminum alloy infiltrates the interstitial spaces between steel spheres. In the PM technique, steel spheres and steel powder are sintered to form a solid, closed cell structure. The measured densities of the Al-Fe composite foam, low carbon steel foam, and stainless steel foam are 2.4, 2.6, and 2.9 g/cm 3 with relative densities of 42, 34, and 37%, respectively. The composite metal foams composite materials developed in this study displayed superior compressive strength as compared to any other foam being produced with similar materials. The compressive strength of the cast Al-Fe foam averaged 67 MPa over a region of 10 to 50% strain, while the low carbon steel PM foam averaged 76 MPa over the same strain region, and the stainless steel PM foam averaged 136 MPa over the same region. Densification began at approximately 50% for the cast foam and ranged from 50 to 55% for the PM foams. The strength to density ratio of the product of both techniques exceeded twice that of foams processed using other techniques with similar materials.

New composite metal foams are processed using powder metallurgy (PM) and gravity casting techniques. The foam is comprised of steel hollow spheres, with the interstitial spaces occupied by a solid metal matrix (Al or steel alloys). The cyclic compression loading of the products of both techniques has shown that the composite metal foams have high cyclic stability at very high maximum stress levels up to 68 MPa. Under cyclic loading, unlike other metal foams, the composite metal foams do not experience rapid strain accumulation within collapse bands and instead, a uniform distribution of deformation happen through the entire sample until the densification strain is reached. This is a result of more uniform cell structure in composite metal foams compared to other metal foams. As a result, the features controlling the fatigue life of the composite metal foams have been considered as sphere wall thickness and diameter, sphere and matrix materials, and processing techniques as well as bonding strength between the spheres and matrix.

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Workplace Managed Care, and a variety of programs related to prevention of substance abuse and related concerns including comorbidity, violence, and the integration of emotional, behavioral, and physical health issues along with related methodological and research issues. She also is an adjunct professor at George