Description
Type 310s is an austenitic chromium nickel stainless steel (.08% max carbon) with good oxidation resistance and strength at high temperatures. It resists oxidation in continuous service up to 2000oF provided reducing sulphur gasses are not present. It is also used for intermittent service at temperatures up to 1900°F because it resists rescaling and has a low coefficient of expansion. This factor reduces the tendency of the steel to warp in heat service. 310s is similar to 310 except for lower carbon content to minimize carbide precipitation during welding.
310S stainless steel
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Standard
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Grade
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Chemical Composition %
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Technique
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Yied strength/Mpa
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Tensile strength/Mpa
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Elongation %
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Hardness
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GB
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0Cr25Ni20
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C≤0.08,Mn≤2.00,Si≤1.50,P≤0.045,S≤0.030,Cr 24.0~26.0,Ni 19.0~22.0
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hot,cold rolled
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≥205
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≥520
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≥40
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HV≤200
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USA
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310S
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JIS
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SUS310S
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German
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/
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Physical Properties
Density, 0.29 lbs/in3 9.01 g/cm3
Electrical Resistivity: microhm-in (microhm-cm):
68°F (20°C): 37.0 (94.0)
Specific Heat: BTU/lb/°F (kJ/kg?K):
32-212°F (0-100°C): 0.12 (0.50)
Thermal Conductivity: BTU/hr/ft2/ft/°F (W/m?K):
At 212°F (100°C): 8.0 (13.8)
At 932°F (500°C):10.8 (18.7)
Mean Coefficient of Thermal Expansion:in/in/°F (μm/m?K)
32 – 212°F (0 -100°C) – 8.0 x 10-6(14.4)
32 – 600°F (0 -315°C) – 9.3 x 10-6(16.7)
32 -1000°F (0 -538°C) –9.6 x 10-6(17.3)
32 -1200°F (0 -649°C) –9.7x 10-6(17.5)
Modulus of Elasticity: ksi (MPa)
29.0 x 103 (200 x 103) in tension
11.2 x 103 ( 78 x 103) in torsion
Magnetic Permeability: H = 200 Oersteds: Annealed < 1.02 max
Melting Range: °F (°C) 2550 – 2650 (1399 – 1454)
Corrosion Resistance
Alloy 310 is not designed for service in wet corrosive environments. The high carbon content, which is present to enhance creep properties, has a detrimental effect on aqueous corrosion resistance. The alloy is prone to intergranular corrosion after long term exposure at high temperatures. However, due to its high chromium content (25%), Alloy 310 is more corrosion resistant than most heat resistant alloys.
High Temperature Corrosion
The high chromium (25%) and silicon (0.6%) content of Alloy 310 make it more resistant to high temperature corrosion in most in-service environments. Operating temperatures are listed below.
Oxidizing conditions (max sulfur content – 2 g/m3)
1922°F (1050°C) continuous service
2012°F (1100°C) peak temperature
Oxidizing conditions (max sulfur greater than 2 g/m3)
1742°F (950°C) maximum temperature
Low oxygen atmosphere (max sulfur content – 2 g/m3)
1832°F (1000°C) maximum temperature
Nitriding or carburizing atmospheres
1562 – 1742°F (850 – 950°C) maximum
The alloy does not perform as well as Alloy 600 (UNS N06600) or Alloy 800 (UNS N08800) in reducing, nitriding or carburizing atmospheres, but it does outperform most heat resistant stainless steels in these conditions.
Hot Forming
Heat uniformly at 1742 – 2192°F (950 – 1200°C). After hot forming a final anneal at 1832 – 2101°F (1000 – 1150°C) followed by rapid quenching is recommended.
Cold Forming
The alloy is quite ductile and forms in a manner very similar to 316. Cold forming of pieces with long-term exposure to high temperatures is not recommended since the alloy is subject to carbide precipitation and sigma phase precipitants.
Welding
Alloy 310 can be readily welded by most standard processes including TIG, PLASMA, MIG, SMAW, SAW and FCAW.
Applications
Cryogenic Components
Food Processing
Furnaces – burners, doors, fans, piping and recuperators
Fluidized Bed Furnaces – coal combustors, grids, piping, wind boxes
Ore Processing/Steel Plants – smelter and steel melting equipment, continuous casting equipment
Petroleum Refining – catalytic recovery systems, flares, recuperators, tube hangers
Power Generation – coal gasifier internals, pulverized coal burners, tube hangers
Sintering/Cement Plants – burners, burner shields, feeding and discharging systems, wind boxes
Thermal Processing – annealing covers and boxes, burner grids, doors, fans, muffles and retorts, recuperators, walking beams