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High-pressure die casting is a highly productive process that yields near net-shape castings at a relatively low cost. One disadvantage of die casting, however, is residual porosity that is inherently present in the castings. Semi-solid die casting is a method that is superior to die casting as it relates to porosity but has historically been a more expensive process. This is due to the higher cost of the billet feed material and the inability to easily recycle billets and runners. Slurry-on-Demand is a new semi-solid casting process that develops the semi-solid slurry directly from the liquid, thereby eliminating the cost penalties intrinsic to the billet semi-solid process. This paper will describe the Slurry-on-Demand process in detail and present case studies comparing the casting of large components using both Slurry-on Demand and conventional high-pressure die casting. It will also provide examples of quality improvements achievable by the Slurry-on-Demand process.

An accelerated test procedure has been developed at Visteon to reduce the component durability test time, while meeting the reliability requirements. The method and procedure are presented in this paper with application examples to wiper motor bearing retainers. The new test speed, load level, and test duration of the accelerated test are derived by employing the CAE durability and reliability techniques. The accelerated test speed is determined based on the dynamic characteristics of the test specimen-fixture-machine system, using the CAE finite element analysis method. The increased test load level is obtained based on CAE dynamic stress simulation, material fatigue model, and durability damage equivalence. The reduced test duration (or number of test cycles) is determined based on CAE equivalent fatigue damage technique and modified from the reliability requirement parameters, such as reliability target, confidence level, and sample size.

There has been considerable investigation into vehicle bumper response in low speed accidents. A bumper to bumper collision often results in very little or no apparent damage even though the collision might have been significant. However, when two vehicles which have considerably different bumper heights collide, the resulting damage quite often is visually extensive but it is confined to relatively weak sheet metal, lighting, and/or grill components. The amount of research dedicated to bumper override in low speed impacts is much more limited. In an effort to add to the base of knowledge relative to low speed bumper override impacts, the authors conducted a series of barrier impacts involving several vehicles with human occupants. The impacts were in the 3 to 8 km/hr range. The vehicles were instrumented with an accelerometer and a velocity sensor. The occupants were instrumented with 8 accelerometers.