Stainless 303se (Selenium)

  • Stainless 303se (Selenium)

    UNS Number S30323

    303Se Stainless Steel is a free machining 18-8 chrome-nickel steel. Selenium, added to an 18-8 stainless steel that is tough and difficult to machine, makes it so easily and freely machinable that it can be readily be handled on automatic screw machines. It can be machined at about 75% of the speed of carbon C1212. This material has displayed nongalling properties that make disassembly of parts easy and help to avoid scratching or galling in its moving parts.

    Type 303Se has somewhat better formability than Stainless Type 303 and should be considered for applications which involve cold-forming operations.

    Type 303Se can been used for parts that are fabricated by machining, grinding and polishing. For example, all types of screw machine products, valves, valve trim, etc. However, it is not recommended for vessels containing gases or liquids under high pressure.

    Stainless Type 303Se is resistant to atmospheric corrosion, foodstuffs, sterilizing solutions, many organic chemicals and dyestuffs, and a wide variety of inorganic chemicals.

    Intergranular corrosion may be a problem if the material is heated between 800ºF (427ºC) and 1650ºF (899ºC) or cooled slowly through that range.

    For optimum corrosion resistance, surfaces must be free of scale, lubricants, foreign particles, and coatings applied for drawing and heading. After fabrication of parts, cleaning and/or passivation should be considered.

    Physical Properties
    Specific Gravity
    -- 7.83
    -- 0.2830 lb/in³
    Mean Specific Heat
    32 to 212°F 0.1200 Btu/lb/°F
    Mean CTE
    32 to 1200°F 10.4 x 10-6 in/in/°F
    Electrical Resistivity
    70°F 433.0 ohm-cir-mil/ft
    Typical Mechanical Properties

    Carpenter Stainless Type 303 Se: Typical Room Temperature Mechanical Properties