ASTM A995: Austenitic-ferritic duplex castings for pressure-containing service

Technical features of duplex castings according to ASTM A995 standard

This specification regulates the production of austenitic-ferritic (duplex) steel castings intended for use in pressure-containing components: valves, flanges, and fittings. Products supplied by EV Group China fully comply with the standard’s requirements for chemical composition and mechanical properties.

Duplex alloys combine high strength and exceptional resistance to stress corrosion cracking. The optimal microstructure, consisting of 30–60% ferritic phase and an austenitic matrix, is achieved through precise control of alloying elements and precision heat treatment. The selection of a specific steel grade for a project remains the responsibility of the design engineer, taking into account operating media, temperature conditions, and mechanical loads.

When placing an order with EV Group China, the following data must be provided:

• Design documentation, including casting tolerances and part specifications;
• The exact volume of the batch (in kilograms or units);
• The current version of the standard and the selected steel grade;
• Specific requirements for non-destructive testing and acceptance methods.

All metal is melted in electric arc furnaces followed by ladle refining, which ensures alloy purity from non-metallic inclusions.

Mechanical properties of duplex steels