X6CrNiNb18-10, 1.4550, X5CrNiNb18-10, 1.4546, AISI 347 - Chromium-Nickel austenitic stainless steel, with the addition of niobium according to EN 10088-1
| Standard | Steel Grade | |||||||
|---|---|---|---|---|---|---|---|---|
| Chemical Composition % | ||||||||
| C: | Mn: | Si: | P: | S: | Cr: | Ni: | Nb: | |
| PN | 0H18N12Nb | |||||||
| <0.080 | <2.00 | <0.80 | <0.045 | <0.03 | 17.00 - 19.00 | 10.00 - 13.00 | <1.10 | |
| DIN/EN | X6CrNiNb18-10 - X 6 CrNiNb 18-10 - 1.4550 | |||||||
| <0.080 | <2.00 | <1.00 | <0.045 | <0.015 | 17.00 - 19.00 | 9.00 - 12.00 | <1.00 | |
| LW | 1.4546 - X5CrNiNb18-10 | |||||||
| <0.080 | <2.00 | <1.00 | <0.045 | <0.030 | 17.00 - 19.00 | 9.00 - 11.50 | <1.00 | |
| EN | X10CrNiNb18-10 | |||||||
| <0.12 | <2.00 | <1.00 | <0.045 | <0.030 | 17.00 - 19.00 | 9.00 - 12.00 | <0.80 | |
| GOST | 08Ch18N10B - 08Kh18N10B - 08Х18Н10Б | |||||||
| <0.08 | <2.00 | <0.80 | - | - | 17.00 - 19.00 | 9.00 - 11.00 | <1.00 | |
| AFNOR | Z 6 CNNb 18-10 - Z6CNNb18-10 | |||||||
| <0.06 | <2.00 | <0.75 | <0.040 | <0.015 | 17.00 - 19.00 | 9.00 - 11.00 | <1.00 | |
| ČSN / STN | S 07Cr20Ni10Nb1 - S07Cr20Ni10Nb1 | |||||||
| <0.07 | 1.20 - 2.50 | 0.20 - 0.70 | <0.025 | <0.018 | 17.80 - 20.70 | 8.75 - 11.25 | <1.25 | |
| DIN | 18-10 Nb - 18-10Nb - 18/8Nb | |||||||
| <0.08 | <2.00 | <1.00 | <0.045 | <0.015 | 17.00 - 19.00 | 9.00 - 12.00 | <1.00 | |
| GB/T | 06Cr18Ni11Nb - S34778 | |||||||
| <0.08 | <2.00 | <1.00 | <0.035 | <0.03 | 17.00 - 19.00 | 9.00 - 12.00 | <1.10 | |
| LW | X5CrNiNb18-10 - X 5 CrNiNb 18-10 - 1.4546 | |||||||
| <0.08 | <2.00 | <1.00 | <0.045 | <0.03 | 17.00 - 19.00 | 9.00 - 11.50 | <1.00 | |
| AISI | AISI 347 - TP347 | |||||||
| <0.08 | <2.00 | <1.00 | <0.045 | <0.03 | 17.00 - 20.00 | 9.00 - 13.00 | <1.10 | |
| SAE | 347H - 347 H | |||||||
| 0.04 - 0.10 | <2.00 | <0.75 | <0.04 | <0.03 | 17.00 - 20.00 | 9.00 - 13.00 | <1.00 | |
| UNS | S34700 - S 34700 | |||||||
| <0.08 | <2.00 | <1.00 | <0.045 | <0.03 | 17.00 - 20.00 | 9.00 - 13.00 | <1.10 | |
1.4550, AISI 347, X6CrNiNb18-10 - characteristics and application
1.4550, is a steel resistant to intergranular corrosion in a heat treated state and after a sensitizing heat treatment. In terms of destination, is akin to the 1H18N9T grade, however, is characterized by higher resistance to oxidation.
Steel products are suitable for deep drawing and are fully weldable. The grade does not require additional heat treatment after welding. Conducted tests according to PN-H-04630 in polish grade 0H18N12Nb test A show that the steel is resistant to intergranular corrosion in the heat treated state and after the sensitizing treatment.
The 1.4550 grade is used in the chemical industry equipment manufacturing nitric acid and derivatives, salts and fertilizers. Also used in cryotechnics, in the pharmaceutical industry, in the food industry - in food processing plants, dairies, sugar factories, breweries, in the fuel industry, i.e. in refineries and petrochemical plants.
Steel intended for pipelines, autoclaves, transport tanks, heat exchangers, absorption towers, pumps, coolers, and reactors.
X6CrNiNb18-10, AISI 347 is characterized by:
- quite a low yield point (~ 220 MPa),
- very good impact resistance at negative temperature
- Impact resistance at the temp. of -253 °C more than 70 J/cm2
- good ductility
- non-magnetism
- very good resistance index at high temperatures
- in a temp. of 500℃ - R0.2 = approx. 120 MPa
- in a temp. of 500℃ - R1,0 - 150 MPa
- a large susceptibility to hardening by crushing
- poor polishability
- very good indicator of durability at high temperatures
Corrosion resistance:
- Pitting corrosion-resistant steel
- Steel resistant to rural and non-industrial urban atmosphere
- Stainless steel less aggressive sea atmosphere
- Steel resistant to salt of nitric acid and nitric acid at concentrations of up to 55% and temperatures up to 80 °C
- Steel resistant to non-oxidizing environments, e.g. H2SO4, HCl, HF, etc.
- Steel resistant to stress corrosion in solutions of chlorides and hydroxides
- Steel resistant to pitting and contact corrosion in environments containing halides
Mechanical and physical properties and heat treatment of X6CrNiNb18-10, 1.4550 steel
| Mechanical and physical properties | ||
|---|---|---|
| Tensile strength | Rm | 510 - 740 MPa |
| The yield point | Rp0.2 | ≥ 205 MPa |
| Hardness | ≤ 230 HB | |
| Modulus of elasticity | E | 200 GPa |
| Elongation | A | ≥ 40% |
| Density | ρ | 7,90 kg/dm³ |
| Thermal capacity | cp20℃ | 500 J ⋅ kg⁻¹ ⋅ K⁻¹ |
| Thermal conductivity | λ | 15 W ⋅ m⁻¹ ⋅ K⁻¹ |
| Supersaturation | 1020 - 1100℃ | |
Properties of X6CrNiNb18-10, 1.4550 at an elevated temperature
| Properties at elevated temperatures | ||||||
|---|---|---|---|---|---|---|
| Properties | Temperature | |||||
| 100℃ | 200℃ | 300℃ | 400℃ | 500℃ | ||
| Linear expansion coefficient | α | 16.0 ⋅ 10⁻⁶ ⋅ K⁻¹ | 16.5 ⋅ 10⁻⁶ ⋅ K⁻¹ | 17.0 ⋅ 10⁻⁶ ⋅ K⁻¹ | 17.5 ⋅ 10⁻⁶ ⋅ K⁻¹ | 18.0 ⋅ 10⁻⁶ ⋅ K⁻¹ |
| The yield point | Re | ≥ 175 MPa | ≥ 155 MPa | ≥ 136 MPa | ≥ 125 MPa | ≥ 119 MPa |
| Modulus of elasticity | E | 194 GPa | 186 GPa | 179 GPa | 172 GPa | 165 GPa |
In the grade of 1.4550, AISI 347 the company provides:
- Rolled bars, drawn bars, peeled bars X6CrNiNb18-10
- Seamless tubes X6CrNiNb18-10
- Cold-rolled strips X6CrNiNb18-10
- Forgings X6CrNiNb18-10
- Cold-rolled sheets X6CrNiNb18-10
- Hot-rolled sheets X6CrNiNb18-10
- Burned sheet elements X6CrNiNb18-10
The list of equivalents and other designations of 0H18N12Nb steel:
08Ch18N10B, 08Kh18N10B, 08Х18Н10Б, X6CrNiNb18-10, X 6 CrNiNb 18-10, 1.4550, 4550, X10CrNiNb18-10, Z 6 CNNb 18-10, Z6CNNb18-10, S 07Cr20Ni10Nb1, S07Cr20Ni10Nb1, 18-10 Nb, 18-10Nb, 18/8Nb, 06Cr18Ni11Nb, S34778, TP347H, AISI 347, AISI 347H