Alloy 31
Introduction:-
Alloy 31 is a nickel, chromium, and molybdenum stainless steel with nitrogen and copper additions. It combines moderate tensile strength and high ductility with excellent corrosion resistance in sulfuric acid, reducing and oxidizing media and has a strong resistance to corrosion and erosion-corrosion in the phosphoric environment.
Typically the alloy has PREN of ≥ 48, which ensures that the resistance to pitting corrosion is high.
Applications for Alloy 31:-
Used in f.ex pulp and paper industry, flue gas desulphurization – FGD – systems, seawater heat exchangers, petroleum production and refining industry, mining industry, ore processing, etc.
Heat Treatment
Solution annealing at min 1150°C followed by water quenching.
Weldability
Very good.
Chemical Composition of Alloy 31:-
| Weight % | C | SI | MN | S | P | CR | NI | MO | N | CU |
|---|---|---|---|---|---|---|---|---|---|---|
| MIN. | 26,0 | 30,0 | 6,0 | 0,15 | 1,0 | |||||
| MAX. | 0,015 | 0,3 | 2,00 | 0,010 | 0,020 | 28,0 | 32,0 | 7,0 | 0,25 | 1,4 |
Mechanical Properties of Alloy 31:-
| Yield streng RP0.2, MPA |
Tensile strength
RM, MPA |
Elongation
[%] |
Hardness
[HB] |
Impact, Charpy-V, -196ºC
[J] |
Pre |
|---|---|---|---|---|---|
| ≥ 276 | ≥ 650 | ≥ 40 | ≥ 140 | ≥ 48 |
Plate Stock for Alloy 31:-
| MEASUREMENTS | KG/PLATE |
|---|---|
| 3 X 2000 X 8000 MM | 408 |
| 5 X 2000 X 8000 MM | 680 |
Alloy 31 Avaliability
- Alloy 31 Seamless Pipe 1/4″ – 8″
- Alloy 31 Weld Pipe 1/2″ – 24″
- Alloy 31 Butt-Weld Fittings 1/2″ – 24″
- Alloy 31 Flanges 1/2″ – 24″
- Alloy 31 Pressure Fittings 1/4″ – 2″
- Alloy 31 150# Fittings 1/4″ – 2″
- Alloy 31 Tubing 1/4″ – 1″
- Alloy 31 Valves 1/2″ – 12″
- Alloy 31 Bar 1/8″ – 11″
- Alloy 31 Plate 1/8″ – 3″
Alloy 31 Specifications
1.4562, 2.4607, 2.4609
Alloy 31 Tensile Requirements
- Tensile Strength <650
- Yield Strength <275