Specification:
ASTM B 729/ASME SB 729
ASTM B 468/ASME SB 468
NACE MR0175
Seamless and welded condition
Maximum service temperature: 500°C / 930°F
Alloy 20 is an austenitic, nickel-iron-chromium based super alloy with additions of copper and molybdenum which provide maximum resistance to acid attack and specifically sulfuric acid. The alloy 20 has excellent resistance to general corrosion, pitting and crevice corrosion in hostile environments. The alloy 20 is stabilized with niobium against sensitization and resultant inter granular corrosion. Alloy 20 appears to fall between both the stainless steel and nickel alloy categories as it contains characteristics of both.
Characteristics:
Market applications:
Technical composition (%) | Fe | Cr | Ni | Mo | Mn | Si | P | C | S | Nb | C |
20 min | Bal. | 19.0 | 32.0 | 2.0 | - | - | - | - | - | - | 3.0 |
max | - | 21.0 | 38.0 | 3.0 | 2.00 | 1.00 | 0.045 | 0.070 | 0.035 | 8xC (1.0 max) | 4.0 |
Mechanical Properties | 20 |
Tensile strenght (mpa, min) | 551 |
Yield strength (0.2% offset mpa, min) | 241 |
Elongation (%, min) | 30 |
Density / weight (g / cm3 / kg) | 8.1 |