1.2083 / X40Cr14 Stainless Tool Steel
1.2083, designated X40Cr14, is a martensitic stainless tool steel defined by a deliberate balance of approximately 0.36–0.42% carbon and 12.5–14.5% chromium. The chromium level qualifies it as stainless, forming a stable passive oxide layer that resists moisture, weak acids, and the aggressive chemical environments generated during PVC processing.
The elevated carbon content enables hardening up to 50–54 HRC—a rare achievement in corrosion-resistant materials. This unique intersection of hardness and corrosion resistance makes it a dominant choice in plastic mold tooling.
A key advantage is its outstanding polishability; with proper treatment, surfaces achieve a mirror finish of Ra ≤ 0.05 μm, essential for optical, medical, and high-gloss consumer molds.
Commercially known as S136 or Stavax ESR, FUSHUN METAL supplies this grade across various forms and melting routes, tailored to your specific cleanliness and performance demands. Contact us for a free quote on your next project.
Equivalent Grades
| Country / Standard Body | Designation |
|---|---|
| Germany / Europe — EN/DIN (Werkstoff-Nr.) | 1.2083 / X40Cr14 |
| USA — AISI/ASTM (equivalent type) | Type 420 / 420HC |
| Japan — JIS | SUS 420J2 |
| China — GB/T | 4Cr13 |
| Russia — GOST | 40Х13 |
| ASSAB (trade name) | S136 |
| Uddeholm (trade name) | Stavax / Stavax ESR |
Applications
1.2083 / S136 is fundamentally a plastic mold steel, but the precise combination of corrosion resistance, high achievable hardness, and polishability extends its relevance into broader applications wherever tooling surfaces must simultaneously resist wear and chemical attack:
- PVC injection molds and extrusion tooling — window profiles, pipe fittings, rigid packaging, and flooring tiles
- Molds for flame-retardant engineering plastics — resins containing halogenated flame retardants that release corrosive gases
- Mold cores and cavities for recycled polymer processing — post-consumer mixed plastics containing unpredictable contaminants
- Optical molds — injection molds for eyeglass lenses, camera lens elements, light guides, and optical diffusers
- CD/DVD and Blu-ray disc molds — stamper-backing and cavity plates requiring high hardness and surface quality
- Medical device molds — syringe bodies, connectors, and pharmaceutical packaging requiring surface cleanliness
- Food-grade packaging molds — caps, closures, containers, and film dies meeting food-contact hygiene requirements
- Extrusion screws, barrels, and nozzles for PVC processing equipment
- Mold inserts, core pins, and ejector sleeves in multi-cavity tools processing corrosive resins
- Precision gauges and measuring fixtures used in humid or chemically active environments
- Cutlery blanks, knife blades, and surgical instrument profiles machined from bar stock
Specifications & Standards
1.2083 / X40Cr14 is classified as a corrosion-resistant cold-work tool steel within the European standard system. In other countries, its equivalent grades are catalogued under stainless steel standards, reflecting different classification philosophies.
| Standard | Grade Designation | Product Forms Covered |
|---|---|---|
| EN ISO 4957 | X40Cr14 (1.2083) | Bars, rods, forgings, flat products |
| ASTM A276 / A276M | Type 420 | Bars and shapes |
| ASTM A240 / A240M | Type 420 | Plate, sheet, and strip |
| JIS G4303 | SUS 420J2 | Stainless steel bars |
| JIS G4304 | SUS 420J2 | Hot-rolled plate, sheet, and strip |
| JIS G4305 | SUS 420J2 | Cold-rolled plate, sheet, and strip |
| GB/T 1220 | 4Cr13 | Stainless steel bars |
| GB/T 3280 | 4Cr13 | Cold-rolled plate and strip |
| GOST 5632 | 40Х13 | Stainless and heat-resistant steel grades |
EN ISO 4957 is the primary standard for 1.2083 as a true tool steel grade, specifying a tightly controlled carbon range. The ASTM Type 420 designation covers a broad stainless family; 1.2083 corresponds specifically to the high-carbon, hardenable end of this family. We can supply material to any of the above specifications as required.
Available Sizes & Delivery
FUSHUN METAL supplies 1.2083 / S136 stainless tool steel in a wide range of product forms. Powered by our 6,000-ton hydraulic forging press and GFM radial forging machine, we ensure large-section forged rounds and flats feature tight dimensional tolerances and consistent internal homogeneity—critical for achieving high mirror polish across the full cavity depth.
Product Forms & Dimensions
| Product Form | Size Range |
|---|---|
| Rolled round bar | Diameter: 16 mm – 300 mm; Length: up to 6,000 mm |
| Forged round bar | Diameter: 80 mm – 1,200 mm; Length: up to 6,000 mm |
| Rolled flat bar | Thickness: 10 mm – 150 mm; Width: up to 600 mm |
| Forged flat bar / block | Thickness: 20 mm – 600 mm; Width: up to 1,500 mm; Length: as required |
| Forged plate | Thickness: 20 mm – 800 mm; Width and length to order |
Lead Times & Minimum Order Quantities
| Order Type | MOQ | Typical Lead Time |
|---|---|---|
| Standard stock sizes (common rolled bar diameters) | 1 piece | ~7 days |
| Custom forged or rolled product | 3 tons | ~30 days |
| Small-batch custom heat (induction furnace) | 3–5 tons | To be confirmed |
| Large-volume orders (EAF production, 30–60 tons) | 30 tons | Expedited schedule |
For mold block supply, we provide forged blocks with milled or ground surfaces in near-net-shape dimensions, minimizing your rough machining allowance. Tell us your requirements for dimensions outside the listed ranges.
Chemical Composition
| Grade | Standard | C (%) | Si (%) max | Mn (%) max | P (%) max | S (%) max | Cr (%) | Ni (%) max |
|---|---|---|---|---|---|---|---|---|
| X40Cr14 (1.2083) | EN ISO 4957 | 0.36–0.42 | 1.00 | 1.00 | 0.030 | 0.030 | 12.5–14.5 | — |
| Type 420 | ASTM A276 | ≥0.15 | 1.00 | 1.00 | 0.040 | 0.030 | 12.0–14.0 | — |
| SUS 420J2 | JIS G4303 | 0.26–0.40 | 1.00 | 1.00 | 0.040 | 0.030 | 12.0–14.0 | — |
| 4Cr13 | GB/T 1220 | 0.36–0.45 | 0.60 | 0.80 | 0.035 | 0.030 | 12.0–14.0 | — |
| 40Х13 | GOST 5632 | 0.36–0.45 | 0.80 | 0.80 | 0.030 | 0.025 | 12.0–14.0 | 0.60 |
The EN ISO 4957 specification sets the tightest carbon and chromium windows, reflecting its intent as a dedicated tool steel grade. All heats are verified against your required specification by OES. Note that 1.2083 does not include molybdenum; if Mo-enhanced corrosion resistance is required, consider 1.2316 (X38CrMo16).
Melting & Processing
FUSHUN METAL offers flexible melting routes for 1.2083 to match your performance needs.
- Standard Route (EAF + AOD + LF + VD): Ensures precise carbon and chromium control for general tooling.
- Enhanced Cleanliness (ESR / PESR): Adds electroslag remelting (or protective atmosphere) to eliminate macro-segregation and reduce inclusions—ideal for optical and medical molds requiring superior mirror polishability.
- Maximum Purity (VIM + VAR): For the most critical applications requiring the highest cleanliness standards.
As a stainless grade, AOD is integrated into the process to prevent chromium loss. Contact us to select the optimal melting route for your project.
Mechanical Properties
Room Temperature Properties by Heat Treatment Condition
| Condition | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation A (%) | Hardness |
|---|---|---|---|---|
| Soft annealed | — | — | — | ≤ 229 HB |
| Q+T — tempered at 580–620°C | 850–1,000 | ≥ 600 | ≥ 12 | ~260–290 HB |
| Q+T — tempered at 150–200°C | ≥ 1,600 | ≥ 1,300 | ≥ 8 | 50–54 HRC |
Approximate Hardness vs. Tempering Temperature
(After austenitizing at 1,000–1,020°C, oil or gas quench)
| Tempering Temperature (°C) | Approximate Hardness (HRC) |
|---|---|
| 150 | ~54 |
| 200 | ~52 |
| 300 | ~48 |
| 500 | ~36–38 |
| 600 | ~28–30 |
Important: Tempering in the 380–480°C range should be avoided due to temper embrittlement risk. Double tempering is recommended for all hardening operations.
Heat Treatment
| Heat Treatment Type | Temperature Range | Soaking Time | Cooling Method |
|---|---|---|---|
| Forging | 1,050–1,150°C (Finish >850°C) | Until uniform | Slow in furnace or insulating medium |
| Soft Annealing | 830–880°C | 1–2 hrs / 25 mm thickness | Furnace cool (≤25°C/h) to <600°C, then air |
| Stress Relieving | 600–700°C | 1–2 hours | Slow furnace cool |
| Hardening (Austenitizing) | 980–1,020°C (Preheat: 400-500°C & 800-850°C) | 15–30 mins | Oil / High-pressure N2 gas / Air (thin sections) |
| Tempering (Max Hardness) | 150–200°C | 1 hr min per cycle | Air (Double temper recommended) |
| Tempering (Balanced) | 250–350°C | 1 hr min per cycle | Air |
| Tempering (Pre-hardened) | 580–620°C | 1 hr min per cycle | Air |
Surface Finish & Machining
FUSHUN METAL provides versatile surface finishes for 1.2083.
Round Bars
- Black surface (as-forged/rolled, ±2–5mm tolerance)
- Turned/peeled (Ra ≤ 3.2μm, h9–h11)
- Precision turned (Ra ≤ 1.6μm, h7–h9)
- Cylindrical ground (Ra ≤ 0.8μm, h6–h7)
Flat Bars & Blocks
- Black (±1–3mm)
- Milled (Ra ≤ 3.2μm, ±0.5mm)
- Surface ground (Ra ≤ 0.8μm, +0/−0.05mm)
- Fine ground finishes down to Ra ≤ 0.4μm are also available.
We also offer CNC machining for near-net-shape profiles and custom cutting. Bright surfaces receive protective oiling, while black surfaces retain mill scale for customer machining.
Quality Assurance & Inspection
Every order at FUSHUN METAL follows a documented quality control sequence:
- Pre-production: Each heat is verified by OES, confirming chemical composition before processing.
- In-process: Thermocouple records document forging and heat treatment temperatures, with intermediate hardness and dimensional checks.
- Post-production Final Inspection: Includes chemical composition analysis, mechanical testing (tensile/yield/elongation/hardness), ultrasonic testing (UT) per SEP 1921 or ASTM A388, dimensional inspection, and metallographic examination (microstructure, inclusion rating).
Corrosion testing can be arranged upon request. We issue EN 10204 3.1 certificates as standard; EN 10204 3.2 and third-party inspection by SGS or TÜV are available. FUSHUN METAL operates under ISO 9001 and AS9100 certified quality management systems.
Packing & Shipping
We tailor packaging to protect your order during transit.
- Black surface products: Securely bundled with steel wire strapping and wooden dunnage to prevent shifting and container damage.
- Bright and ground surface products: Individually coated with rust-preventive oil, wrapped in VCI moisture-barrier film, and protected with kraft paper or foam; nylon strapping replaces steel wire to prevent surface marking.
All products receive anti-rust oil and VCI desiccants for maritime shipping, ensuring rust-free delivery regardless of destination humidity. Shipping terms include FOB, CFR, CIF, DDU, and DDP.
Frequently Asked Questions
Can you cut 1.2083 / S136 to my specific block or bar dimensions?
Yes. Cutting to specified lengths, widths, and thicknesses is a standard service. For mold blocks, we commonly supply forged flat bars with milled surfaces in dimensions close to your target, minimizing the stock removal required in your workshop. Inquire with your dimensions and quantity.
What is the hardness of 1.2083 in annealed condition, and can you supply it pre-hardened?
In the soft-annealed condition, 1.2083 has a hardness of ≤ 229 HB. After hardening and tempering at 150–200°C, it achieves approximately 50–54 HRC. We can also supply pre-hardened mold blocks at 28–34 HRC (tempered at 580–620°C), which are ready for direct CNC machining without in-house heat treatment. Please specify your target hardness range when requesting a quotation.
What is the practical difference between standard 1.2083 and S136 or Stavax ESR?
1.2083 is the standardized EN/DIN designation. S136 and Stavax are commercial trade names. The meaningful technical distinction is the melting route: "Stavax ESR" and "S136 Supreme" indicate ESR quality, which significantly reduces non-metallic inclusions and produces superior mirror polishability compared to standard EAF-route 1.2083. At FUSHUN METAL, we supply both standard and ESR/PESR-remelted material. Tell us your application and required surface finish, and we will confirm which route is appropriate.
Is 1.2083 genuinely suitable for molds processing PVC?
Yes — PVC mold tooling is a primary application for this steel. During PVC processing, hydrogen chloride gas attacks conventional tool steel surfaces, causing pitting. The 12.5–14.5% chromium content in 1.2083 forms a stable passive film that resists this attack. For the best corrosion resistance, we recommend ESR-quality material, hardened to at least 48 HRC, with a polished cavity surface of Ra ≤ 0.1 μm.
