Material Specification for Investment Casting 3

[rjsme]

How does one go about specifying a material for a part that will be investment cast? If I want the as cast properties to be equivalent to AISI 1020, for instance, would I specify it that way or are there other standards/specs that are specifically geared for investment casting? I am new to investment castings, so any info on the subject would be appreciated.

 

[metengr]

rjsme;
You have several options to obtain cast steel specifications; one option is use ASTM (American Society for Testing and Materials) Standards for investment castings (ASTM A 957-03 titled "A957-03 Standard Specification for Investment Castings, Steel and Alloy, Common Requirements, for General Industrial Use"). You would have to purchase this from ASTM if you do not have access to their database. Including additional reference documents pertaining to your metal selection.

Your second option is to use the following web site that will provide you with a supplement to the Steel Castings Handbook, issued by the Steel Founder's Society of America. Even though this is a supplement, it provides a basic overview of the various steel and alloy steel casting specifications and associated properties. You could purchase the Handbook. In fact, I had purchased a used handbook for a nominal cost - it is an excellent reference document

http://www.sfsa.org/sfsa/pubs/hbk/s2.pdf

 

[Steeltip]

netengr is right that ASTM or the SFSA documents can guide you. There are also a number of on line sites that (for a fee) will provide the references.

1020 can have a very broad range of properties depending on the heat treating. The properties can also vary greatly in the finished part depending on the method of manufacture.

You mentioned inverstment castings and there can be great ranges in casting properties dependent upon the methods used by the foundry. I would recommend both specifying the material and a sampling process.