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The use of magnesium cast components has become very important in reducing the automobile vehicle weight, thereby reducing fuel consumption. In the past, such parts have been limited to structural applications. The USAMP/USCAR Structural Casting Magnesium Development (SCMD) project team has successfully demonstrated that an application of a structural magnesium casting to an engine cradle is quite feasible. Computer simulation of casting processes becomes an essential tool for this development, since cradle applications are unprecedented. Numerous simulations were conducted to visualize the effect of geometry changes, process parameter changes, vacuum, and shot parameter changes. These results were used to identify the best possible configuration.

Casting and welding processes introduce defects which can grow to failure under fatigue loading. It is necessary to analyze such defects to estimate fatigue lifetimes or strength loss from uninspectable flaws. An accurate analysis should include stress gradients, singular crack stress fields, and multiple flaw interactions. It must also be easily applicable to irregularly shaped mechanical components. However, it is not feasible to mesh defects due to the tedium involved, and the need to evaluate several “what if” damage scenarios. The finite element alternating method addresses these issues conveniently and accurately. It models defects by means of analytical crack stress functions, which are superimposed on systematic uncracked finite element meshes to achieve true stress fields. Functions are available for embedded or surface elliptic flaws, and other defect shapes.