Technical director, Cannon-Muskegon Corp., Muskegon, Mich.
Pages: 11 Published: Jan 1982
Alloy 12.5 percent chromium (AMS 5350, ASTM A 743; Grade CA 15) is a corrosion-resistant and heat-resistant alloy with which a broad range of mechanical properties may be obtained through thermal processing. It is readily hardened and tempering temperatures up to 732°C (1350°F) produce a broad range of strength coupled with good impact resistance.
This paper presents the problems encountered within master alloy preparation and castings resulting from such preparation, with mechanical properties meeting specification requirements but resulting in field failures upon impact. Specific details regarding the chemical and mechanical property evaluations of the contaminated material are described.
Controlled additions of contaminant (tin) of varying concentrations were made to laboratory melts and subjected to specification test requirements. Test results show the deleterious effect of tin on impact values with no change in results when compared with standard specification mechanical property requirements. A request for changes in chemical composition residual elements has been made with supporting test data.
martensitic stainless steel, mechanical properties, residual tin levels, Charpy V-notch impact values, castings, master alloy
Paper ID: STP28442S