Nickel and nickel alloys · Alloy 33 / UNS R20033 / 1.4591
Alloy 33 (UNS R20033): Engineering Reference Guide to Properties and Applications
Engineering Parameters of Alloy 33 (UNS R20033)
| Product forms | Trade and International Designations | Key Standards and Specifications | Standard Equivalents | ||
|---|---|---|---|---|---|
| Forgings, wire | Alloy 33, Nicrofer S 3033, VDM Alloy 33, UNS R20033 | ASTM | ASME | W.Nr. | ISO |
| Forgings, wire | Alloy 33, Nicrofer S 3033, VDM Alloy 33, UNS R20033 | B 366, B 462, B 472, B 564, B 619, B 622, B 625, B 626, B649, B 924 | SB 462, SB 619, SB 622, SB 625, SB 626, SB 649 | 1.4591 | 14175, 14343-A |
| Forgings, wire | Alloy 33, Nicrofer S 3033, VDM Alloy 33, UNS R20033 | B 366, B 462, B 472, B 564, B 619, B 622, B 625, B 626, B649, B 924 | SB 462, SB 619, SB 622, SB 625, SB 626, SB 649 | 1.4591 | 14175, 14343-A |
Elemental Composition of Alloy 33 in Percentage (%)
| Ni | 30.0-33.0 |
|---|---|
| Cu | 0.3-1.2 |
| Cr | 31.0-35.0 |
| Mo | 0.5-2.0 |
| Mn | <2.0 |
| N | 0.35-0.60 |
| C | <0.015 |
| Si | <0.5 |
| S | <0.01 |
| P | <0.02 |
| Fe | <0.40 |
Mechanical Characteristics under Standard Conditions
| Tensile Strength (Rm) | Yield Strength (Rp0.2) | Elongation at Break (A) |
|---|---|---|
| 750 MPa | 380 MPa | 40 % |
Physical-Mechanical Properties and Corrosion Resistance
Alloy 33, with a density of 8.1 g/cm³, is a highly alloyed chromium austenitic material designed for operation in extreme oxidizing environments. Its unique formula, balanced with molybdenum and copper, provides excellent resistance to localized corrosion types such as pitting and crevice corrosion, making it an optimal choice from EV Group China for environments where standard stainless steels are ineffective.
The presence of nitrogen at a concentration of up to 0.60% is a critically important alloying element. It stabilizes the austenitic phase and promotes the formation of a fine-grained microstructure after heat treatment (annealing). This, in turn, provides the material with an exceptional combination of high impact toughness and increased yield strength.
Key Industrial Applications
Products made from Alloy 33 by EV Group China are used in critical components of chemical and energy equipment. These include heat exchangers, reactors, and piping systems for concentrated sulfuric acid. The material is also indispensable in pickling baths based on nitric-hydrofluoric acids, in seawater desalination plants, and in equipment for the pulp and paper industry that operates with aggressive bleaching agents.
The weldability of Alloy 33 is ensured by modern methods such as gas tungsten arc welding (GTAW/TIG), plasma welding, and laser welding. To guarantee the preservation of the original corrosion resistance of the weld seam and the heat-affected zone, it is necessary to use welding materials with a chemical composition identical to the base metal.