S136 Material Detailed Information
S136 is a high-purity stainless tool steel developed for plastic mold applications requiring excellent corrosion resistance, polishability, and wear resistance. It is widely used in the medical, optical, and food packaging industries, where high surface quality and durability are critical.
S136 is the equivalent of DIN 1.2083, AISI 420 modified, and SUS420J2, but with improved hardness and corrosion resistance.
Key Features
- Excellent Corrosion Resistance: Suitable for humid environments and corrosive plastics.
- High Polishability: Ideal for optical and high-gloss mold applications.
- Good Wear Resistance: Durable for long production runs.
- High Hardness: Can reach 50-52 HRC after heat treatment.
- Dimensional Stability: Maintains precision after machining and heat treatment.
Chemical Composition
| Element | Composition (%) |
| Carbon (C) | 0.38 – 0.45 |
| Chromium (Cr) | 12.50 – 14.50 |
| Manganese (Mn) | ≤ 0.50 |
| Silicon (Si) | ≤ 0.80 |
| Phosphorus (P) | ≤ 0.030 |
| Sulfur (S) | ≤ 0.030 |
Mechanical Properties
| Property | Value |
| Hardness (Annealed) | ≤ 215 HB |
| Hardness (Hardened & Tempered) | 50-52 HRC |
| Tensile Strength | 1,900 MPa |
| Yield Strength | 1,600 MPa |
| Elongation | 10-15% |
| Corrosion Resistance | Excellent |
S136 vs. 1.2083 vs. 420 vs. 1.2316
| Property | S136 | 1.2083 | 420 (AISI) | 1.2316 |
| Corrosion Resistance | Excellent | Good | Moderate | Excellent |
| Polishability | Superior | Good | Moderate | Good |
| Hardness (After Tempering) | 50-52 HRC | 48-50 HRC | 48-50 HRC | 45-50 HRC |
| Wear Resistance | High | Medium | Medium | Medium |
| Machinability | Moderate | Good | Good | Good |
Applications
S136 is mainly used in plastic mold manufacturing, including:
- Injection molds for transparent plastics (e.g., lenses, food packaging)
- Medical device molds
- Optical component molds
- High-humidity plastic molds
- Corrosive plastic molds (e.g., PVC, acetate, and flame-retardant plastics)
Heat Treatment Process
Annealing
- Heat at 850–900°C
- Slow cooling in a furnace to below 600°C, then air cooling
Hardening
- Heat to 1,020–1,050°C, hold for proper soaking time
- Quench in oil, vacuum, or air
Tempering
- Heat at 200–300°C
- Temper twice for optimal mechanical properties
- Hardness after tempering: 50-52 HRC
Alternative Materials
- 1.2083 (DIN) – A lower-cost alternative with similar corrosion resistance but slightly lower hardness
- 420 Stainless Steel (AISI) – Similar in composition but with less polishability and hardness
- 1.2316 – Higher corrosion resistance but lower hardness than S136
Conclusion
S136 is an excellent high-purity stainless steel for plastic mold applications requiring corrosion resistance, high polishability, and durability. It is widely used in the medical, optical, and food packaging industries
