Choosing the right tool steel can make or break your manufacturing project. Three grades dominate precision tooling and mold making: 1.2316, 1.2085, and 1.2311. These are popular choices, but they’re not interchangeable. Each grade has different strengths. One offers superior corrosion resistance. Another provides exceptional hardness. The third gives balanced machinability. Pick the wrong one? You risk premature tool failure, expensive downtime, or poor product quality.
This comparison breaks down the technical details in plain language. You’ll see how 1.2316 vs 1.2085 vs 1.2311 tool steel differ in chemical makeup, mechanical performance, and real-world applications. Making plastic injection molds, precision dies, or demanding industrial components? You’ll find which steel grade fits your specific needs. We back everything with data-driven analysis and practical selection criteria. This saves you both time and money.
Overview of 1.2316 vs 1.2085 vs 1.2311 Tool Steel
These three tool steel grades work for different manufacturing needs. 1.2085 (X33CrS16) is a stainless steel built for corrosive plastic molding. It comes pre-hardened at around 33 HRC. You can harden it up to 56 HRC if needed. The sulfur content makes it easy to machine. This gives you better machinability than 1.2316 while keeping strong wear resistance.
1.2311 (P20) goes by AISI P20 or DIN 40CrMo7 worldwide. This mold steel puts easy machining first. Drilling, milling, and turning get done faster. So processing costs drop. The chromium and molybdenum give good wear resistance. But it has no corrosion protection. You need heat treatment to get the best performance.
1.2316 is the top choice for corrosion resistance. This stainless tool steel handles tough chemical environments. It matches 1.2085 in hardness and wear resistance. The downside? Machining takes longer. You’ll use more time and resources on machining. Plus, it costs more than the other two.
Each grade solves different manufacturing problems. 1.2085 gives you corrosion resistance and easy machining. 1.2311 cuts costs and processes easily. 1.2316 offers the best corrosion protection for harsh conditions. Your application needs decide which one wins.
Chemical Composition
These three tool steels differ in their chemical makeup. This affects how they perform. Tiny changes in alloying elements cause big shifts in rust resistance, ease of cutting, and where you can use them.
| Element | 1.2316 | 1.2085 | 1.2311 |
|---|---|---|---|
| C (%) | 0.33-0.45 | 0.33 | 0.35-0.45 |
| Si (%) | ≤1.00 | Balanced | 0.20-0.40 |
| Mn (%) | ≤1.00 | Balanced | 1.30-1.60 |
| P (%) | ≤0.030 | ≤0.030 | ≤0.030 |
| S (%) | ≤0.030 | Higher (machinability boost) | ≤0.030 |
| Cr (%) | 15.50-17.50 | ~16.00 | 1.80-2.10 |
| Mo (%) | 0.80-1.30 | Present | 0.15-0.25 |
| Ni (%) | ≤1.00 | – | – |
Key Chemical Takeaways
Chromium is the Shield: With ~16% Cr, 1.2316 and 1.2085 actively fight corrosion from PVC acids. 1.2311 lacks this layer and risks rusting.
Sulfur Equals Speed: 1.2085 adds sulfur to break chips easily, cutting machining time by up to 20% compared to the others.
Stability Factors: Molybdenum gives 1.2316 heat resistance, while Manganese aids 1.2311’s deep hardening.
The Bottom Line: Minor chemical shifts decide if your tool resists rust, cuts faster, or withstands impact.
Mechanical Properties
Let’s talk about what happens right out of the box. 1.2085 arrives effectively hard at ~33 HRC. If you need immediate wear resistance without extra steps, this is your starting point. You can also heat treat it up to 50-54 HRC for extreme durability. 1.2316 is your “steady” choice. It comes pre-hardened around 30 HRC (280-325 HB). You skip the heat treatment entirely, keeping the hardness consistent from surface to core. 1.2311 is the softer sibling. Delivered at 28-32 HRC, it works well for general tasks. However, it’s softer than its two counterparts unless you treat it further.
| Property | 1.2316 | 1.2085 | 1.2311 |
|---|---|---|---|
| Delivery Hardness | ~30 HRC (pre-hardened) | ~33 HRC (pre-hardened) | 28-32 HRC |
| Max Hardness | 280-325 HB (~30 HRC) | 50-54 HRC (heat-treated) | HRC 28 (H+T) |
| Toughness | Good, lower impact | Excellent, good ductility | Higher than 1.2085 |
| Wear Resistance | Good (high Cr) | Superior | Moderate |
| Heat Treatment | None needed | Required for max hardness | Required |
Toughness: Where 1.2311 Shines
1.2311 is the clear winner for toughness. It absorbs shock better than the others. If your mold faces sudden stress or heavy impact, this grade resists cracking best. 1.2085 is reliable too. It offers excellent ductility, meaning it flexes rather than breaks under stress. 1.2316? It’s decent, but be careful. While the uniform hardness helps, it doesn’t handle heavy mechanical shocks as well as the others (or grades like 1.2344). Keep it away from high-impact jobs.
Wear Resistance: Where 1.2085 Shines
Dealing with abrasive materials? 1.2085 is your best bet. Once heat-treated to 50-54 HRC, it fights off wear remarkably well. Glass-filled plastics and rough fillers struggle to scratch it. 1.2316 uses its chromium shield to fight wear. It performs well, but it can’t quite match the hardness of heat-treated 1.2085. 1.2311 stays in the middle. It offers moderate resistance, suitable for standard molds but likely to wear down faster under harsh conditions.
A note on stability: 1.2316 offers precision without the warp risk. Since you skip heat treatment, your dimensions stay put. Tolerances under 0.01mm are realistic. With 1.2085 and 1.2311, you need to plan ahead. Heat treatment involves high temperatures, which can shift metal. Allow for some movement.
Key Properties Comparison
Compare these steels side-by-side to see where each one works best. These differences help you pick the right grade for your tooling needs.
| Property | 1.2316 | 1.2085 | 1.2311 |
|---|---|---|---|
| Corrosion Resistance | Excellent (15.5-17.5% Cr, PVC-ready) | Excellent (similar to 1.2316, S-enhanced) | Poor (non-stainless, needs coating) |
| Wear Resistance | Excellent | Superior to 1.2316 | Good (standard mold grade) |
| Hardness Range | 235 HB annealed / 28-33 HRC hardened | 33 HRC pre-hardened (as-delivered) | 30 HRC pre-hardened |
| Machinability | Good (uniform structure) | Superior (sulfur boost) | Excellent (P20-type base) |
| Polishability | Superior (mirror finish capable) | Good | Good |
| Dimensional Stability | High | High | High |
| Toughness | Good (heat resistant) | Good (no heat treatment stress) | High (best impact resistance) |
Corrosion Protection Performance
Both 1.2316 and 1.2085 resist rust very well. They contain 15.5-17.5% chromium. This creates a protective oxide film. The film guards against PVC, acidic additives, and humid factories. Both grades stand up to harsh plastics without pitting. 1.2311 can’t handle corrosive conditions. Its chromium level stays under 2.1%. You need protective coatings here. Or stick to dry, non-corrosive uses only.
Machinability and Production Efficiency
1.2085 machines the fastest of the three. Its added sulfur creates manganese sulfide bits. These break chips clean. You’ll cut 15-20% faster than with 1.2316. 1.2311 machines well too. Its P20-type makeup cuts smooth in pre-hardened form. Tooling costs stay low. 1.2316 takes more machining time. Its dense chromium fights your cutting tools. Plan extra time for complex shapes. Tool wear runs higher here.
Surface Finish Capabilities
1.2316 gives you the best surface polish. Its even hardness lets you reach mirror finishes below Ra 0.05 µm. Optical molds need this level. So do precision medical devices. 1.2085 and 1.2311 polish well. They hit standard mold finish specs. But neither gets as smooth as 1.2316.
Dimensional Stability Across All Grades
All three grades hold their shape well. Pre-hardened delivery cuts warping during production. You can hold tight specs under 0.01mm. No stress relief needed. This cuts extra work and scrap.
Pick 1.2316 for corrosive plastics that need top finish. Choose 1.2085 for rust protection plus faster machining. Go with 1.2311 for general molding without rust issues. Look at your main need—rust resistance, machining speed, or cost control. That tells you the winner.
Applications
Each steel grade solves specific manufacturing problems. The table below shows where 1.2316, 1.2085, and 1.2311 work best in real production.
| Steel Grade | Best Used For | Delivery State | Top Advantage |
|---|---|---|---|
| 1.2316 | PVC molds, Medical devices, High-gloss electronics | Pre-hardened (~30 HRC) | Maximum corrosion protection & mirror polishing |
| 1.2085 | Glass-filled plastics, Automotive structural parts, Mold frames | Pre-hardened (~33 HRC) *Can be treated to 50-54 HRC |
Superior wear resistance & 20% faster machining |
| 1.2311 | General rubber/plastic molds, Non-corrosive prototypes | Pre-hardened (28-32 HRC) | Lowest cost & excellent impact toughness |
Industry-Specific Application Guidance
Each steel has a “sweet spot” where it outperforms the others. Here is the breakdown to help you match the steel to your specific job.
1. 1.2316: The Corrosion & Polish Specialist
This grade dominates when chemistry fights against you. It is the go-to choice for corrosive plastic processing.
Fights Acid Attacks: PVC releases hydrochloric acid during molding. With ~16% chromium, 1.2316 creates a stable oxide shield that blocks acid.
Mirror Finish Ready: Need high-gloss for consumer electronics? Its uniform structure polishes down to Ra 0.05 µm without “orange peel” defects.
Medical Safety: No rust means no contamination. It keeps sterile parts clean.
humid Factories: Even your cooling channels stay rust-free. No more clogged lines or rust stains on Monday mornings.
⚠️ Critical Warning: Do not nitride 1.2316. The high chromium content blocks nitrogen, causing a brittle surface layer that flakes off under stress. Skip this step.
2. 1.2085: The Wear Resistance Warrior
When you are running abrasive materials, soft steel dies fast. 1.2085 is your armor against wear.
Handles “Sandpaper” Plastics: Glass-filled plastics act like sandpaper inside a mold. Heat treat this grade to 50-54 HRC, and your cutting edges stay sharp far longer than with 1.2316.
Automotive Durability: Ideal for transmission components and steering parts that face high stress.
Optical Longevity: It maintains dimensional clarity in optical molds, even after high-volume processing cycles.
3. 1.2311: The Budget-Friendly Generalist
Not every job needs “superhero” steel. For standard tasks, 1.2311 gets the job done without breaking the bank.
Cost Effective: You save roughly 20-30% on material costs compared to stainless grades.
Better than Basic P20: It offers a cleaner structure and better polishing results than standard P20, reaching HRC 28-30 easily.
Standard Duty: Perfect for rubber molds and non-corrosive plastics (like PE or PP) where rust isn’t a threat.
3-Question Selection Checklist
Stop guessing. Answer these three questions to find your winner.
1. Is your plastic corrosive? (PVC, Flame Retardants)
YES → You need 1.2316 or 1.2085. (Check question 2)
NO → Stick to 1.2311 and save ~25% on material costs.
2. Does the part require a mirror finish? (Optical, High-Gloss)
YES → 1.2316 is your only safe choice. The sulfur in 1.2085 ruins optical clarity.
3. Are you molding with abrasive fillers? (Glass Fibers)
YES → Choose 1.2085 and heat treat it to 50-54 HRC. It will outlast the others by far.
Quick Selection Chart
| Your Priority | Recommended Grade | Key Benefit |
|---|---|---|
| Corrosive plastics + mirror finish | 1.2316 | Best polish, excellent rust protection |
| Corrosive plastics + fast machining | 1.2085 | 15-20% faster cutting, good finish |
| Maximum wear resistance | 1.2085 (heat treated to 50-54 HRC) | Longest tool life with abrasives |
| Lowest material cost | 1.2311 | 20-30% savings versus stainless grades |
| Non-corrosive plastics | 1.2311 | Cost-effective, good machinability |
Conclusion
Your choice between 1.2316 vs 1.2085 vs 1.2311 tool steel depends on what you need for your project. Need great corrosion resistance and mirror-polishing for plastic molding? 1.2316 is your best pick. For precision cutting tools that need extreme hardness and wear resistance, 1.2085 performs best. 1.2311 works well for general mold production. It’s easy to machine and costs less.
The right steel grade affects your production speed, tool life, and product quality. Think about your work environment. Check what surface finish you need. Look at your budget. Consider how long you need the tool to last.