Normally, castings are specified according to a recognized Standard or Specification. The common material/testing Standards are ASTM or even SAE.

Once you have determined the correct Standard for the casting, you need to obtain a copy and review it. Standards will provide guidance as to the type of mechanical tests and requirements for the tests. Supplemental reference documents in the Standard will describe the test specimens and their locations.

For materials, there are ASTM material specifications.

The ASTM specifications will list the appropriates testing procedures under the referenced documents. Using the appropriate procedures you wil determine the properties. Pay attention to the reporting requirements.

Dick

ASTM specifications also give the crucial detail of whether separate test bars may be cast or if test specimens must be cut from a production casting. Sometimes, this is negotiable between manufacturer & purchaser. See
ASTM A781/A781M-06 Standard Specification for Castings, Steel and Alloy, Common Requirements, for General Industrial Use.
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