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The springback of simple geometries can be predicted through theoretical analysis, however problems arise when transferring this analysis to the manufacturing environment. To determine why this is the case, a study of small curvature free bending through theoretical analysis, manufacturing data and Finite Element (FE) simulation was completed. The theoretical analysis provided an understanding of the behavior of springback and gave accurate predictions in a controlled environment. The manufacturing and Finite Element data verified the trends predicted by theory, but lacked in accuracy. The paper concludes by proposing a prediction method based solely on the geometry that is well defined in both environments.

A Split Hopkinson Pressure Bar (SHPB) was used to obtain dynamic behaviour of various steels at large strains and high strain rate. The dynamic loading response was compared between mild steels and cold rolled high strength steels, Dual Phase 590 and TRIP 780. Only sheet samples were available for the high strength steels, and thus confirmation tests were carried out on mild steel to determine whether behaviour of sandwiched samples were equivalent to normal bulk samples. The effect of pre-straining and bake hardening on dynamic behaviour of sheet metals was then investigated. Preliminary results show a difference between the bake hardening effect on pre-strained Dual Phase and TRIP steels. Bake hardening increased the mass specific energy absorption for the pre-strained Dual phase sample, whereas the pre-strained TRIP sample mass energy absorption decreased. Further work is necessary to verify this difference and understand the material behaviours.

This work examines the design and implementation of a new runner and gating system for an existing cast iron exhaust manifold. Three designs were tested. Pressurized and unpressurized systems were trialed to determine which system produces better results in gravity casting. Runner, gate and sprue areas were varied to control the peak linear velocity during filling. These trials gave high defect levels for peak velocities over 2.0 m/s in pressurized and unpressurized systems, and the pressurized systems significantly reduced slag inclusions. A pressurized system with larger runner sections reduced the casting defect rate tenfold when peak gate velocity was limited to 1.0 m/s.