Dimensional Variability of Aluminum Castings
The dimensional capabilities of production aluminum castings are described. More than 480 production casting features have been evaluated for jobbing shop aluminum castings made in green sand and permanent molds. A comprehensive database of casting, feature and process descriptors has also been developed, so that the influence of these factors on casting dimensional variability can be evaluated.
Measurement system analysis techniques have been used to ensure that the dimensional variability measured was not influenced by excessive measurement system errors. The dimensional variability of both green sand and permanent-mold castings is less than is suggested by International Standards Organization (ISO) casting dimensional tolerance specifications.
Both feature length and casting weight significantly influenced the dimensional variability of aluminum castings produced in permanent molds. The dimensional repeat-ability of aluminum castings is also compared to rile dimensional repeat-ability of iron and steel castings from similar studies.