1.2085 / X33CrS16 – Stainless tool steel with good polishability and excellent machinability
Steel 1.2085 (X33CrS16) is a martensitic stainless tool steel with an increased sulphur (S) content, which significantly improves machinability. While maintaining good corrosion resistance and dimensional stability, it is ideal for moulds, inserts and components that require fast production and a good surface finish.
It is mainly used in the plastics industry, where a combination of corrosion resistance, good surface quality and easy machining is required.
Properties of 1.2085
🛡️ Good corrosion resistance
A chromium content of around 15–17% provides high corrosion resistance in plastic-processing environments and humid conditions.
🔧 Excellent machinability
The increased sulphur content (0.10–0.30%) significantly improves chip-forming machinability.
✨ Good polishability
Suitable for moulds and inserts requiring a quality surface finish. Not at the optical level of 1.2083, but still very good.
🔩 Stable hardness after hardening (48–52 HRC)
Sufficient for standard moulds, cores and machined functional parts.
🧼 Resistant to plastic fumes and chemicals
Suitable for plastics containing aggressive additives.
Chemical composition of 1.2085 (X33CrS16)
| Element | Content (%) |
|---|---|
| C | 0.32 – 0.38 |
| Cr | 15.00 – 17.00 |
| Mn | ≤ 1.00 |
| Si | ≤ 1.00 |
| S | 0.10 – 0.30 |
| P | ≤ 0.040 |
Typical applications of 1.2085
🧩 Plastic moulds
- mould inserts
- core components
- segments and shaped elements
🔧 Fast production of precision parts
- components where machinability is the priority
- small mould parts
🛡️ Components exposed to corrosive environments
- sliding and moving parts
- parts exposed to aggressive plastic fumes
⚙️ Mechanical engineering components
- stainless cutting parts
- precision parts requiring a smooth surface finish
Heat treatment (guideline values)
| Process | Temperature | Note |
|---|---|---|
| Soft annealing | 740 – 800 °C | hardness approx. 190–210 HB |
| Hardening (austenitising) | 980 – 1040 °C | oil / air |
| Tempering | 180 – 250 °C | target: 48–52 HRC |
| Nitriding | 480 – 520 °C | improves wear resistance |
| Preheating | 750 – 800 °C | recommended |
Mechanical properties
- Hardness after hardening: 48–52 HRC
- Hardness in annealed condition: 190–210 HB
- Excellent machinability due to sulphur addition
- Good corrosion resistance
- Good polished surface quality
