X9CrNiSiNCe21-11-2, 1.4835, 253MA - High-alloy heat-resistant chromium-silicon-nickel steel with the addition of cerium and nitrogen according to EN 10088-1 and EN 10095.
| Standards | Steel Grades | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Chemical Composition % | ||||||||||
| C: | Mn: | Si: | P: | S: | Cr: | Mo: | Ni: | Ce: | N: | |
| EN / DIN | X9CrNiSiNCe21-11-2 - 1.4835 - X 9 CrNiSiNCe 21-11-2 - 4835 | |||||||||
| 0.05 - 0.12 | <1.00 | 1.40 - 2.50 | <0.045 | <0.015 | 20.00 - 22.00 | - | 10.00 - 12.00 | 0.030 - 0.080 | 0.12 - 0.20 | |
| GOST ISO | X7CrNiSiNCe21-11 | |||||||||
| 0.05 - 0.10 | <0.80 | 1.40 - 2.00 | <0.040 | <0.030 | 20.00 - 22.00 | - | 10.00 - 12.00 | 0.030 - 0.080 | 0.14 - 0.20 | |
| SANDVIK | 253 MA® - 253MA® - MA253 | |||||||||
| 0.08 | <0.80 | 1.60 | <0.040 | <0.040 | 21.00 | - | 11.00 | 0.050 | 0.17 | |
| Outokumpu | 253 MA® - 253MA® | |||||||||
| 0.05 - 0.10 | <0.80 | 1.40 - 2.00 | <0.04 | <0.015 | 20.00 - 22.00 | <0.54 | 10.00 - 12.00 | 0.030 - 0.080 | 0.14 - 0.20 | |
| ASTM | UNS S 30815 - UNS S30815 | |||||||||
| 0.05 - 0.10 | <0.80 | 1.40 - 2.00 | <0.040 | <0.030 | 20.00 - 22.00 | - | 10.00 - 12.00 | 0.030 - 0.080 | 0.14 - 0.20 | |
| RA | RA 253 MA - RA253MA - RA 253MA | |||||||||
| 0.05 - 010 | <0.80 | 1.40 - 2.00 | <0.04 | <0.03 | 20.00 - 22.00 | - | 10.00 - 12.00 | 0.030 - 0.080 | 0.14 - 0.20 | |
253MA®, X9CrNiSiNCe21-11-2, 1.4835 - description and specification
Heat-resistant austenitically high-alloyed steel with cerium, used in isothermal conditions, ideal for temperatures up to 700 - 1100oC. At higher temperatures, it exhibits high abrasion resistance and thermal expansion, resistance to deformation, high creep resistance, sulphation (sulfur compounds), erosion and corrosion, oxidation, exhaust gases in cyclical circulation, and steam.
Steel, unlike the X15CrNiSi25-21, contains less chromium and nickel, which contributes to the implementation of more cost-effective project solutions. In addition, the performance of the alloy allows the use of smaller dimensions and thinner thickness of products in the majority of applications when compared to the common austenitic CrNiSi steels. Addition of nitrogen reduces material embrittlement phase σ.
Main feature of 253MA® steel is a surface which is coated with a protective layer of Cr2O3 oxide. It should also be added that the 253MA® steel (X9CrNiSiNCe21-11-2, 1.4835) is an easily accessible grade and, despite the austenitic structure, catches up with the resistance to sulfur compounds X10CrAlSi18, 1.4742, and consistently X10CrAlSi24, 1.4762.
The X9CrNiSiNCe21-11-2 grade has good resistance in carburizing atmospheres, gas carburizing and nitriding, but the AISI 310 and AISI 314 (X15CrNiSi25i, 1.4841 equivalents) are still much better.
253MA®, 1.4835 and X9CrNiSiNCe21-11-2 is used, inter alia, as steel for ash hopper covers, glass foundry molds, pipe hooks, heat exchangers, recuperators, valves, tubular guards, combustion chambers, impact separators, turbine and fan rotors, fireproof anchors, CFBC boilers, exhaust manifolds, heat treatment stands, steelworks, glass and cement industries, radiator pipes, air heating pipes in sulfuric acid gas converters, thermocouple tubes, burner components, heat treatment furnace tubes and styrene reactors and convection tubes.
253MA®, X9CrNiSiNCe21-11-2, 1.4835 steel - Creep limit and creep resistance at elevated temperatures
| Properties at temperatures elevated | Temperatures | |||||
|---|---|---|---|---|---|---|
| 600℃ | 700℃ | 800℃ | 900℃ | 1000℃ | ||
| Creep resistance | Rz/1000 | 238 MPa | 105 MPa | 50 MPa | 24 MPa | 12 MPa |
| Creep resistance | Rz/10000 | 157 MPa | 63 MPa | 27 MPa | 13 MPa | 7 MPa |
| Creep resistance | Rz/100000 | 88 MPa | 35 MPa | 15 MPa | 8 MPa | 4 MPa |
| Creep limit | R1/1000 | 170 MPa | 66 MPa | 31 MPa | 15.5 MPa | 8 MPa |
| Creep limit | R1/10000 | 126 MPa | 45 MPa | 19 MPa | 10 MPa | 5 MPa |
| Creep limit | R1/100000 | 80 MPa | 26 MPa | 11 MPa | 6 MPa | 3 MPa |
Mechanical and physical properties of 253MA®, X9CrNiSiNCe21-11-2, 1.4835 steel in annealed condition +AT
| The mechanical properties of X9CrNiSiNCe21-11-2 according to EN 10095 | ||
|---|---|---|
| Tensile strength | Rm | 650 - 850 MPa |
| Yield point | Re | < 310 MPa |
| Elongation | A | > 37% |
| Hardness | HB | < 210 HB |
| Density | ρ | 7,80 kg/dm3 |
| Heat capacity | cp20-100℃ | 500 J ⋅ kg-1 K-1 |
| Linear Expansion Factor | α20-100℃ | 17.0 - 19.5 ⋅ 10-6 K-1 |
| Heat conductivity | λ20℃ | 15 W ⋅ m-1 ⋅ K-1 |
| Electrical resistance | ρ | 0.85 ⋅ 10-4 Ω ⋅ cm |
Heat treatment and thermo-mechanical treatment of 253MA®, X9CrNiSiNCe21-11-2, 1.4835 steel - temperatures and process
| Heat treatment and thermo-mechanical treatment | |||
|---|---|---|---|
| Process | Cooling | Time | Temperatures |
| Softening annealing | fast in the air or water | 5 - 20 min. | 1020 - 1120℃ |
| stress relief annealing | szybkie w powietrzu | < 30 min. | 850 - 950℃ |
| Thermo-mechanical treatment | 900 - 1150℃ | ||
Bending, forming and welding of 253MA®, X9CrNiSiNCe21-11-2, 1.4835 steel
As with other high-alloyed austenitic steels, X9CrNiSiNCe21-11-2 is easy for cold working. For X15CrNiSi25-21, 1.4841, for 253 MA products due to addition of nitrogen - N, it is necessary to use more force when cold forming steel.
Steel tends to spring, so it will be necessary to apply compensation. After cold bending you do not have to, but it is recommended in the case of bending, among others, pipes, to subject the product that will work at temperatures above 800oC to annealing. Hot bending should be carried out at temperatures of 850 - 1100oC. The plasticity of X9CrNiSiNCe21-11-2 is much better than plasticity of ferritic steels.
Welding of X9CrNiSiNCe21-11-2 steel is performed by arc welding by coated electrodes at 650 - 950oC, pure argon, plasma, and MIG (Ar + 0.03% NO, or Ar + 30% He + approx. 2.25% Co2). TIG and MIG provide the best creep resistance at high temperatures.
Available products:
- Heat-resistant plates, sheets 253MA, X9CrNiSiNCe21-11-2, 1.4835
- Rolled heat-resistant bars 253MA, X9CrNiSiNCe21-11-2, 1.4835
- Seamless Tubes 253MA, X9CrNiSiNCe21-11-2, 1.4835
List of equivalents and other determinations of X9CrNiSiNCe21-11-2, 1.4835 steel:
X 9 CrNiSiNCe 21-11-2, 4835, X7CrNiSiNCe21-11, 253 MA®, 253MA®, MA253, UNS S 30815, UNS S30815, 1.4893, 4893, X8CrNiSiN21-11, X 8 CrNiSiN 21-11, RA 253 MA, RA253MA, RA 253MA.