surface imperfection spec for cast iron

[kevinthompson]

Hello,
I am searching for the specification max surface imperfections and defects depth (especially impurities such as SiO2, FeO2 etc) for cast iron (especially ductile) automotive powertrain parts.
Unfortunateşy up to now i have not found clear specification.
The part is supplied in cast state then machined ,the question is for cast condition
I will appreciate for your valuable comments and suggestions.
Regards

 

[dbooker630]

You should get a copy of the Manufacturers Standardization Society's Specification MS-SP-55. This document contains visual acceptance standards for typical as-cast surface conditions. This is a good starting reference but you may need to adjust your acceptance level based on your application.

Allowable depths must take soundness characteristics into consideration, what is permissible in gate and riser areas, etc. Also consider the number of discontinuities in a particular area. These aspects are not in MS-SP-55. ASTM E446 and its associated radiographs can help you establish the allowable internal discontinuity level.

 

[metengr]

Agree with the last post. You will need to either adopt an existing code or standard most applicable to your service conditions or you will need to develop your own acceptance criteria.

 

[kevinthompson]

Thank you very much for your answers, this really helps.
From the documents these papers seems to evaluate general surface.
Can you please share if there is a spec available for microstructure evaluation for impurities (especially impurities such as SiO2, FeO2 etc) for cast iron (especially ductile)surface longaditional section.
thank you very much