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The effects of casting conditions and hot deformation processing on the mechanical properties of aluminum and magnesium cast composites were determined. A356 Al-20 vol.% SiCp composite ingot from Dural Composite Corporation was either squeeze cast under 140 MPa pressure or sand cast into a cylindrical shape. Both castings were subsequently hot worked via hot swaging to reductions of 33% to 95%. The AZ91 Mg-20 vol.% SiCp composites were prepared at Case Western Reserve University followed by either permanent mold and sand casting techniques to produce keel bars or squeeze casting at 140 MPa pressure. The squeeze cast Mg-SiCp cylinders were additionally hot extruded at 12:1 reduction ratio. Tensile strengths of A356 composite in the T6 condition improved from 235 to 280 MPa with squeeze casting: the tensile strength further increased to 339 MPa with hot deformation processing.

Application of phosphate treatments to zinc-coated steel strip prior to stamping operations is termed prephosphating. Prephosphate treatments have been shown to improve zinc-coated steel strip formability in automotive stamping processes and its corrosion resistance during storage and transport prior to painting. A program was undertaken to establish the range of prephosphate coating weights which improve formability without significantly altering spot weldability, adhesive bonding characteristics and final phosphating immediately prior to painting. The effects of coating untreated and prephosphated galvannealed steel with mill oil were also examined. When galvannealed steel with predominantly a delta-phase surface was prephosphated with a trication phosphate coating weight of ∼1.5 g/m2, an 11% reduction in forming load was measured with cup tests. Limiting dome height analysis showed a 27% improvement in performance by prephosphating.

Recent advances in press and die building have provided the capability of restraining force (RF) variation during a sheet stamping stroke. Even though the commercial presses with VRF capabilities are now available, the full benefits cannot be attained because, for complex industrial stampings, it is difficult to select the VRF trajectory which will improve the stamping quality or achieve even more complex task of arriving at the desired design target. In this paper we demonstrate how numerical modeling can be used to select a proper VRF trajectory to achieve a postulated design target. The working numerical model using explicit LS-Dyna 3D code was successfully developed for time effective simulation of complex parts with variable binder force. Three case studies with the specific design targets of 1) springback, 2) punch force, and 3) maximum strain are presented and discussed. The results show strong nonlinear influence.