【国外标准】 Standard Specification for Ferritic Malleable Iron Castings

This specification covers ferritic malleable castings for general engineering usage. The castings are classified as Grade 32510. The chemical composition of the iron shall be such as to produce the structural and mechanical properties required by this specification. Tension test may be machined from the standard cast bar to the required dimensions. The microstructure of the malleable iron shall consist of temper carbon nodules distributed through ferritic matrix and shall be free of excessive pearlite, massive carbides, and primary graphite. All castings, on visual examination, shall be sound and free of obvious shrinkage and porosity. The castings shall conform to the dimensions given by this specification.1.1 This specification2 covers ferritic malleable castings for general engineering usage at temperatures from normal ambient to approximately 400 °C [750 °F].1.2 No precise quantitative relationship can be stated between the properties of the iron in various locations of the same casting and those of a test specimen cast from the same iron (see Appendix X1).1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.