20KH23N18 / 20X23H18 / 20Х23Н18 Heat-Resistant Stainless Steel
Russian Metals is a supplier, stockist and exporter of 20KH23N18 stainless steel, also identified as 20X23H18, 20X23N18, 20x23h18, 20Х23Н18 and ЭИ417.
20KH23N18 is a highly alloyed chromium-nickel austenitic steel developed for components operating at elevated temperatures. Its combination of approximately 22–25% chromium and 17–20% nickel provides good heat resistance, oxidation resistance and structural stability in demanding thermal environments.
Russian Metals supplies 20KH23N18 heat-resistant steel in sheets, plates, coils, strips, round bars, forged bars, pipes, tubes, wires, flanges, fittings and custom-cut forms. Material can be supplied for furnace equipment, combustion chambers, petrochemical systems, refinery equipment, thermal-processing machinery and other high-temperature industrial applications. Customers can request material according to the required GOST specification, dimensions, heat-treatment condition, testing requirements and certification requirements.
Click any heading below to directly scroll to that section.
Short Grade Introduction
20KH23N18, written in Russian as 20Х23Н18, is a heat-resistant and oxidation-resistant chromium-nickel stainless steel grade. The grade is commonly selected for industrial equipment that requires resistance to scaling and oxidation under elevated-temperature service.
The grade is also known by the following names:
- 20X23H18 stainless steel
- 20X23N18 stainless steel
- 20x23h18 stainless steel
- 20KH23N18 Russian steel
- Сталь 20Х23Н18
- Жаропрочная сталь 20Х23Н18
- Жаростойкая сталь 20Х23Н18
- Сталь ЭИ417
- Сплав ЭИ417
- EI417 heat-resistant steel
Quick Specification Overview
| Specification | Details |
|---|---|
| Main grade | 20KH23N18 |
| Alternative Latin names | 20X23H18, 20X23N18, 20x23h18 |
| Russian designation | 20Х23Н18 |
| Additional designation | EI417, ЭИ417, Х23Н18 |
| Steel type | Chromium-nickel austenitic stainless steel |
| Classification | Heat-resistant and oxidation-resistant steel |
| Applicable base standard | GOST 5632 |
| Chromium content | 22–25% |
| Nickel content | 17–20% |
| Maximum carbon content | 0.20% |
| Density at 20°C | Approximately 7900 kg/m³ |
| Common international comparison | AISI 310, AISI 310S, EN 1.4845 |
| Weldability | Limited weldability |
| Available forms | Sheet, plate, coil, strip, bar, forging, pipe, tube and wire |
Grade Names and Alternative Designations
Searches for 20KH23N18 steel grade often use different Latin and Cyrillic spellings for the same Russian material designation.
| Designation type | Grade name |
|---|---|
| Standard Latin transliteration | 20KH23N18 |
| Alternative Latin designation | 20X23H18 |
| Alternative search spelling | 20X23N18 |
| Lowercase search spelling | 20x23h18 |
| Cyrillic Russian designation | 20Х23Н18 |
| Short Russian designation | Х23Н18 |
| Development designation | EI417 |
| Cyrillic development designation | ЭИ417 |
| Russian product phrase | Сталь 20Х23Н18 |
| Russian heat-resistant phrase | Жаростойкая сталь 20Х23Н18 |
| Russian high-temperature phrase | Жаропрочная сталь 20Х23Н18 |
In the designation 20Х23Н18, the approximate alloy description is: 20 indicates the nominal maximum carbon range used in the grade designation. Х23 indicates approximately 23% chromium. Н18 indicates approximately 18% nickel. Actual chemical composition must be confirmed through the material test certificate supplied with the batch.
20KH23N18 Chemical Composition
Chemical Composition of 20KH23N18 / 20Х23Н18
| Element | C | Si | Mn | Ni | S | P | Cr |
|---|---|---|---|---|---|---|---|
| Content, % | Max. 0.20 | Max. 1.00 | Max. 2.00 | 17.00–20.00 | Max. 0.020 | Max. 0.035 | 22.00–25.00 |
The high chromium content supports oxidation and scaling resistance, while the high nickel content supports an austenitic structure and stability under elevated-temperature service. The actual 20KH23N18 chemical composition should be verified against heat number, product standard, material test certificate, purchase specification, customer-approved composition limits and required international equivalent.
20KH23N18 Mechanical Properties
Mechanical Properties at 20°C
| Product form | Dimension | Direction | Tensile strength, MPa | Yield strength, MPa | Elongation, % | Reduction of area, % | Heat treatment |
|---|---|---|---|---|---|---|---|
| Pipe, Ø212 × 60 mm | Ø212 × 60 mm | Longitudinal | 500 | 200 | 35 | 50 | Quenching at 1100–1150°C, air cooling |
| Bar, GOST 5949-75 | — | Longitudinal | 490 | 196 | 35 | 50 | Quenching at 1100–1150°C, air cooling |
| Thick sheet, GOST 7350-77 | — | — | 540 | 265 | 35 | — | Quenching at 1030–1130°C, water cooling |
| Thin sheet, GOST 5582-75 | — | — | 510 | 245 | 35 | — | Quenching at 1080–1150°C, water cooling |
| Thin sheet, GOST 4986-79 | — | — | 570 | — | 19–38 | — | Quenching at 1050–1080°C, air cooling |
Mechanical properties vary according to product thickness, diameter, manufacturing method, heat-treatment condition, testing direction, applicable GOST standard, and cold- or hot-working condition. The values in the supplied material certificate should always take priority over generic grade data.
20KH23N18 Physical Properties
Physical Properties at Different Temperatures
| Temperature, °C | Elastic modulus ×10⁵, MPa | Thermal expansion ×10⁶, 1/°C | Thermal conductivity, W/(m·°C) | Density, kg/m³ | Heat capacity, J/(kg·°C) | Electrical resistivity ×10⁹, Ω·m |
|---|---|---|---|---|---|---|
| 20 | 2.04 | — | 13.8 | 7900 | — | 1000 |
| 100 | — | 14.9 | 15.9 | — | 538 | — |
| 200 | — | 15.7 | — | — | — | — |
| 300 | 1.86 | 16.6 | 18.8 | — | — | — |
| 400 | 1.80 | 17.3 | — | 7760 | — | — |
| 500 | 1.73 | 17.5 | — | 7720 | — | — |
| 600 | 1.63 | 17.85 | 21.7 | 7670 | — | — |
| 700 | 1.53 | 17.85 | — | 7620 | — | — |
| 800 | 1.44 | — | — | — | — | — |
| 900 | — | — | — | 7540 | — | — |
Key Physical Property Summary
| Property | Approximate value or behaviour |
|---|---|
| Density at 20°C | 7900 kg/m³ |
| Thermal conductivity at 20°C | 13.8 W/(m·°C) |
| Electrical resistivity at 20°C | 1000 ×10⁻⁹ Ω·m |
| Elastic modulus at 20°C | 2.04 ×10⁵ MPa |
| Thermal expansion | Increases with temperature |
| Density at elevated temperature | Gradually decreases as temperature rises |
20KH23N18 Equivalent Grades Comparison
International Equivalent and Nearest Grades
| Country or standard | Equivalent or nearest grades |
|---|---|
| USA – AISI/UNS | 310, 310S, 314, S31000, S31008, S31400 |
| Germany – DIN/WNr | 1.4845, CrNi25-20, X12CrNi25-21, X15CrNiSi25-20, X16CrNi25-20, X8CrNi25-21, X8CrNiSi25-21 |
| Japan – JIS | SUH310, SUS310, SUS310S |
| France – AFNOR | Z12CN25-20, Z12CN26-21, Z8CN25-20 |
| United Kingdom – BS | 310S16, 310S24, 310S25, 310S31 |
| European standards | X8CrNi25-21, 1.4843, 1.4845 |
| Italy – UNI | X8CrNi25-21, X22CrNi25-20, X6CrNi25-20, X6CrNi25-21, X6CrNi25-21KG |
| Spain – UNE | F.331, X8CrNi25-21 |
| China – GB | 1Cr25Ni20Si2 |
| Sweden – SS | 2361 |
| Bulgaria – BDS | 7RE10AE, 8RE10R, Ch23N18 |
| Hungary – MSZ | H9, G205 |
| Poland – PN | H23N18, H25N20S2 |
| Romania – STAS | 12NiCr250 |
| Czechia – CSN | 17255 |
| Australia – AS | 310S |
| South Korea – KS | STS310S |
Both exact and nearest analogues are included. Chemical limits, mechanical properties and product standards may differ.
20KH23N18 vs AISI 310
Grade Comparison Table
| Comparison point | 20KH23N18 / 20Х23Н18 | AISI 310 |
|---|---|---|
| Standard system | Russian GOST designation | American AISI/ASTM designation |
| Typical chromium range | 22–25% | Approximately 24–26% depending on specification |
| Typical nickel range | 17–20% | Approximately 19–22% depending on specification |
| Maximum carbon in supplied data | 0.20% | Depends on exact 310 specification |
| Structure | Austenitic | Austenitic |
| Main purpose | Heat-resistant industrial components | High-temperature and oxidation-resistant components |
| Common comparison status | Base Russian grade | Common nearest international analogue |
| Substitution | Requires technical approval | Requires technical approval |
Is 20KH23N18 Equivalent to AISI 310?
AISI 310 is one of the most commonly listed equivalents or nearest analogues of 20KH23N18. However, the grades are not automatically interchangeable. Before using AISI 310 in place of 20Х23Н18, compare carbon content, chromium and nickel limits, tensile and yield properties, heat-treatment requirements, product form, dimensional standard, elevated-temperature strength, oxidation-resistance requirements, welding procedure, and inspection and certification requirements.
20KH23N18 vs AISI 310S
AISI 310S has a lower carbon limit than standard AISI 310. The supplied data for 20KH23N18 permits carbon up to 0.20%, meaning 310S should not be described as an exact replacement without checking the required composition.
| Comparison point | 20KH23N18 | AISI 310S |
|---|---|---|
| Carbon level | Up to 0.20% in supplied data | Lower-carbon 310 variant |
| Chromium-nickel system | High Cr-Ni | High Cr-Ni |
| Heat resistance | Designed for elevated-temperature use | Designed for elevated-temperature use |
| Weldability | Listed as limited | Generally selected where lower carbon is beneficial |
| Exact equivalence | Not guaranteed | Must be approved based on specification |
Key Properties and Benefits
Main Properties of 20KH23N18 Steel
20KH23N18 offers a combination of properties required for high-temperature equipment:
- High chromium-nickel alloy content
- Resistance to oxidation at elevated temperatures
- Resistance to high-temperature scaling
- Austenitic structure
- Good thermal stability
- Useful strength at elevated temperatures
- Resistance to many industrial atmospheres
- Suitability for furnace and thermal-processing components
- Availability in multiple product forms
- Compatibility with GOST-based industrial designs
Commercial Benefits
Russian Metals can support customers requiring:
- Russian GOST steel grades
- 20KH23N18 custom-size material
- 20Х23Н18 material under order
- Cut-to-size sheets and plates
- Pipes and tubes for thermal equipment
- Round bars and forgings
- Material with mill test certificates
- Export packaging
- Project-specific inspection
- International equivalent comparison
Working Temperature and Heat Resistance
20KH23N18 is designed for high-temperature and heat-resistant applications. It is commonly considered where ordinary stainless steel grades may experience excessive scaling, oxidation or loss of performance.
The physical-property table includes data up to 900°C, but this should not be treated as a universal maximum working temperature.
The actual 20KH23N18 maximum temperature depends on:
- Continuous or intermittent operation
- Applied mechanical stress
- Operating atmosphere
- Sulfur content in the atmosphere
- Combustion products
- Thermal cycling
- Component thickness
- Welding condition
- Required service life
- Oxidation allowance
- Furnace or equipment design
For pressure-retaining equipment, the allowable temperature and stress must be determined from the governing design code.
Corrosion and Oxidation Resistance
Oxidation Resistance
The high chromium content of 20Х23Н18 heat-resistant steel supports the formation of a protective chromium-rich oxide layer. This property makes the grade suitable for furnace interiors, hot gas systems, thermal-processing equipment, combustion-related components, high-temperature enclosures and oxidizing industrial atmospheres.
Corrosion Resistance
20KH23N18 provides corrosion resistance in many industrial environments, but it should not be treated as universally resistant to every chemical medium. Performance depends on chemical concentration, temperature, moisture, chloride content, sulfur-containing gases, reducing or oxidizing conditions, surface finish, weld quality and exposure duration.
Heat Treatment Details
The supplied technical data lists solution treatment or quenching temperatures according to product form.
| Product form | Heat-treatment temperature | Cooling method |
|---|---|---|
| Pipe | 1100–1150°C | Air cooling |
| Bar, GOST 5949-75 | 1100–1150°C | Air cooling |
| Thick sheet, GOST 7350-77 | 1030–1130°C | Water cooling |
| Thin sheet, GOST 5582-75 | 1080–1150°C | Water cooling |
| Thin sheet, GOST 4986-79 | 1050–1080°C | Air cooling |
Heat treatment should be carried out according to product thickness, manufacturing route, required grain structure, applicable GOST standard, final mechanical-property requirements and approved production procedure. Uncontrolled heat treatment may affect grain size, oxidation, dimensional stability and mechanical performance.
Welding Information
20KH23N18 Weldability
The technological data classifies 20KH23N18 weldability as limited. This does not mean that the grade cannot be welded. It means welding requires controlled procedures and appropriate technical planning.
Welding considerations include:
- Suitable filler-metal selection
- Controlled heat input
- Proper joint preparation
- Prevention of contamination
- Interpass-temperature control
- Distortion management
- Weld-root protection
- Post-weld cleaning
- Inspection of critical joints
- Qualification of the welding procedure
For high-temperature or pressure-retaining equipment, welding should be performed under an approved welding procedure specification.
Machining and Fabrication Details
20KH23N18 has a high alloy content and an austenitic structure. This can make machining more demanding than machining ordinary carbon steel.
Machining Recommendations
- Use rigid machines and tooling
- Use sharp cutting tools
- Avoid tool rubbing
- Maintain sufficient cutting depth
- Use suitable coolant where permitted
- Control heat generation
- Allow for work hardening
- Use stable feed rates
- Select tooling for high-alloy stainless steel
Forming and Fabrication
The grade may be processed through suitable industrial methods such as cutting, rolling, bending, forming, forging, welding, machining, drilling, turning and grinding. Fabrication procedures should consider the material's thermal expansion and work-hardening behaviour.
Available Product Forms
Russian Metals can supply or source 20KH23N18 in the following forms.
| Product form | Russian product term | Supply description |
|---|---|---|
| Stainless steel sheet | Лист 20Х23Н18 | Hot-rolled or cold-rolled sheet |
| Heat-resistant sheet | Жаростойкий лист 20Х23Н18 | Sheet for elevated-temperature equipment |
| Steel plate | Плита 20Х23Н18 | Standard or custom-cut plate |
| Coil | Рулон 20Х23Н18 | Full-width or slit coil |
| Strip | Лента 20Х23Н18 | Precision-width or industrial strip |
| Round bar | Круг 20Х23Н18 | Rolled or machined round bar |
| Rod | Пруток 20Х23Н18 | Straight-length bar or rod |
| Forged bar | Кованый круг 20Х23Н18 | Forged round or custom forging |
| Forging | Поковка 20Х23Н18 | Custom forged component |
| Seamless pipe | Бесшовная труба 20Х23Н18 | Seamless pipe for high-temperature service |
| Welded pipe | Сварная труба 20Х23Н18 | Welded pipe according to specification |
| Furnace tube | Жаропрочная труба 20Х23Н18 | Tube for furnace or thermal equipment |
| Wire | Проволока 20Х23Н18 | Industrial and heat-resistant wire |
| Flanges | Фланец 20Х23Н18 | Custom flanges |
| Fittings | Фитинги 20Х23Н18 | Custom industrial fittings |
| Fasteners | Крепеж 20Х23Н18 | High-temperature fastening components |
Available Sizes and Dimensions
Product dimensions depend on mill availability, order quantity and the applicable product standard.
Russian Metals can quote:
- Standard-size sheets
- Custom-cut sheets
- Thick plates
- Hot-rolled plates
- Cold-rolled sheets
- Full coils
- Slit coils
- Narrow strips
- Round bars
- Forged bars
- Custom forgings
- Seamless pipes
- Welded pipes
- Furnace tubes
- Wires
- Cut blanks
For an accurate quotation, provide grade designation, product form, thickness or wall thickness, width, length, outside diameter, inside diameter where required, quantity, heat-treatment condition, applicable standard, certification requirement and delivery location.
Applicable GOST, ASTM and EN Standards
| Standard system | Relevant designation or use |
|---|---|
| GOST 5632 | Russian alloyed stainless and heat-resistant steel grades |
| GOST 5949-75 | Stainless and heat-resistant steel bars |
| GOST 7350-77 | Thick corrosion-resistant and heat-resistant steel sheets |
| GOST 5582-75 | Thin corrosion-resistant and heat-resistant steel sheets |
| GOST 4986-79 | Cold-rolled stainless and heat-resistant strip or sheet |
| AISI | 310, 310S and 314 comparisons |
| UNS | S31000, S31008 and S31400 |
| EN | 1.4843, 1.4845 and X8CrNi25-21 comparisons |
| DIN | CrNi25-20 and related chromium-nickel designations |
| JIS | SUS310, SUS310S and SUH310 comparisons |
| BS | 310S16, 310S24, 310S25 and 310S31 |
The order must state the actual governing standard. An equivalent-grade name alone is not sufficient for technical procurement.
Main Applications
20KH23N18 is used for components exposed to elevated temperatures, oxidation and demanding industrial conditions.
Furnace Equipment
Furnace components, furnace tubes, furnace linings, furnace trays, furnace supports, thermal shields, high-temperature structural parts, heat-treatment baskets, retorts and internal furnace assemblies.
Russian search phrases include: 20Х23Н18 для печного оборудования, 20Х23Н18 для деталей печей, 20Х23Н18 для работы при высокой температуре.
Combustion Equipment
Combustion-chamber components, burner components, hot-gas ducts, exhaust components, high-temperature housings, thermal barriers.
Russian product phrase: 20Х23Н18 для камер сгорания.
Petrochemical and Refinery Equipment
Petrochemical processing components, refinery thermal equipment, high-temperature process piping, hot-gas systems, pyrolysis equipment, methane-conversion equipment, methane-reforming equipment.
Chemical Processing Equipment
High-temperature chemical equipment, reactor components, process-vessel internals, heated pipelines, thermal-processing systems, oxidation-resistant structural components.
Heating and Thermal Equipment
Heating-element support components, thermal-processing equipment, high-temperature fixtures, heat-treatment equipment, industrial heating systems, oxidation-resistant furnace material.
Industries Served
Russian Metals supplies 20KH23N18 material for:
- Furnace manufacturing
- Heat-treatment plants
- Petrochemical processing
- Oil refineries
- Chemical-processing plants
- Gas-processing facilities
- Power generation
- Thermal-equipment manufacturing
- Industrial engineering
- Metal processing
- High-temperature fabrication
- Equipment manufacturing
- Process-piping projects
- Export engineering projects
Quality Testing and Inspection
Testing can be arranged according to the purchase specification and agreed inspection scope.
Chemical Testing
Chemical-composition verification may include carbon, chromium, nickel, silicon, manganese, sulfur, phosphorus and positive material identification.
Mechanical Testing
Depending on product form and specification: tensile-strength testing, yield-strength testing, elongation testing, hardness testing, reduction-of-area testing and elevated-temperature testing where specified.
Dimensional and Surface Inspection
Thickness inspection, diameter inspection, wall-thickness inspection, length inspection, flatness inspection, straightness inspection, surface-condition inspection, visual inspection, identification and marking verification.
Additional Inspection Options
Subject to agreement: third-party inspection, ultrasonic testing, dye-penetrant testing, positive material identification, customer-witnessed inspection, pre-dispatch inspection and document review.
Material Test Certificate Details
20KH23N18 material can be offered with certification where specified in the enquiry and purchase order.
Available documentation may include:
- Mill test certificate
- Chemical-composition certificate
- Mechanical-test results
- Heat-number identification
- Product-standard reference
- Heat-treatment condition
- Dimensional inspection report
- Third-party inspection report
- Certificate of conformity
- Country-of-origin documentation
- EN 10204 3.1 certificate where contractually available
Certification availability depends on the manufacturer, product form, order quantity and agreed supply conditions.
Packaging and Export Documentation
Russian Metals can arrange packaging suitable for domestic transport or export shipment.
Packaging Options
- Wooden boxes
- Wooden crates
- Steel strapping
- Waterproof wrapping
- Protective sheet wrapping
- End protection for pipes
- Bundled bars
- Palletized products
- Identification tags
- Heat-number marking
- Export-grade seaworthy packaging where specified
Export Documentation
Documentation may include commercial invoice, packing list, certificate of origin, material test certificate, inspection certificate, shipping documentation, product identification details, export declaration documents and customer-specific documentation where agreed.
Why Choose Russian Metals?
Russian Metals supports customers requiring difficult-to-source Russian and GOST-grade materials.
| Benefit | Description |
|---|---|
| Supply of 20KH23N18 material | Direct access to Russian-origin heat-resistant steel |
| Latin & Cyrillic grade recognition | Full support for 20Х23Н18 and all spelling variants |
| International equivalent comparison | Assistance comparing AISI 310, 310S, EN 1.4845 and others |
| Complete product range | Sheets, plates, bars, pipes, tubes and wires |
| Custom-size sourcing | Non-standard dimensions and cut-to-size material |
| Project-based procurement | Tailored supply for industrial requirements |
| Mill test certificate support | Chemical, mechanical and inspection documentation |
| Inspection coordination | Third-party and customer-witnessed inspection options |
| Export packaging | Seaworthy packaging for international delivery |
| Commercial support | Bulk and custom order quotations |
Frequently Asked Questions
What is 20KH23N18 stainless steel?▾
20KH23N18 is a Russian chromium-nickel austenitic heat-resistant stainless steel containing approximately 22–25% chromium and 17–20% nickel. It is used for furnace, petrochemical, combustion and thermal-processing equipment.
Is 20X23H18 the same as 20KH23N18?▾
Yes. 20X23H18 is a commonly used Latin-character variation of the Russian grade 20Х23Н18. 20KH23N18 is a more direct transliteration.
What does 20Х23Н18 mean?▾
The designation indicates a high-alloy steel containing approximately 23% chromium and 18% nickel. The initial number relates to the nominal carbon designation used in the Russian grade system.
What is EI417 steel?▾
EI417, written in Cyrillic as ЭИ417, is an additional designation associated with 20KH23N18 or 20Х23Н18 heat-resistant stainless steel.
What is the AISI equivalent of 20KH23N18?▾
AISI 310 is one of the most commonly listed equivalents or nearest analogues. AISI 310S, AISI 314 and related UNS grades may also appear in equivalent-grade tables.
Is 20KH23N18 exactly equivalent to AISI 310?▾
Not necessarily. The grades are similar high-chromium, high-nickel austenitic heat-resistant steels, but their composition limits, mechanical properties and product standards may differ.
Is 20KH23N18 equivalent to AISI 310S?▾
AISI 310S is commonly listed as a nearest comparison. However, 310S has a lower carbon limit, so it should not automatically be treated as an exact replacement.
What is the EN equivalent of 20KH23N18?▾
EN 1.4845 and X8CrNi25-21 are commonly listed as European comparisons. EN 1.4843 may also appear in equivalent-grade references.
What is the chemical composition of 20KH23N18?▾
The supplied composition includes up to 0.20% carbon, up to 1.00% silicon, up to 2.00% manganese, 17–20% nickel and 22–25% chromium.
What is the density of 20KH23N18?▾
The approximate density at 20°C is 7900 kg/m³.
Can 20KH23N18 be welded?▾
Yes, but its weldability is classified as limited. Welding should be completed using a controlled and qualified procedure.
Does Russian Metals supply 20KH23N18 with an MTC?▾
Material can be supplied with a mill test certificate where certification is specified and included in the quotation and purchase order.
How can I get the 20KH23N18 price per kg?▾
Send the required product form, dimensions, quantity, standard, certification requirement and delivery location. Russian Metals will prepare a quotation based on current availability and supply conditions.
Is 20KH23N18 suitable for furnace equipment?▾
Yes. It is commonly considered for furnace parts, furnace tubes, heat-treatment fixtures, thermal shields and other oxidation-resistant high-temperature components.
20KH23N18 Heat-Resistant Steel with MTC, Stock and Export Support
Get 20KH23N18, 20X23H18 and 20Х23Н18 heat-resistant stainless steel in sheets, plates, bars, pipes, tubes and coils with mill test certificates and fast quotation assistance.
Direct sourcing of Russian-origin heat-resistant steel.
Chemical, mechanical and inspection support.
Cut-to-length and non-standard dimensions.
Seaworthy packaging for international delivery.