If you work with high-speed machining or need tools that stay sharp under heat and pressure, EN 1.3343 high speed steel is a game-changer. This alloy is built for tough cutting tasks—from milling hard metals to drilling precision holes—thanks to its exceptional red hardness and wear resistance. In this guide, we’ll break down its key properties, real-world applications, how it’s made, and how it compares to other cutting materials. By the end, you’ll know if it’s the right choice for your high-performance tool needs.
1. Material Properties of EN 1.3343 High Speed Steel
EN 1.3343’s reputation as a top-tier high speed steel comes from its carefully balanced composition and standout properties. Let’s break this into four critical areas:
1.1 Chemical Composition
The elements in EN 1.3343 work together to boost heat resistance, hardness, and durability—essential for high-speed cutting. Below is its typical composition (per EN standards):
| Element | Content Range (%) | Key Role |
|---|---|---|
| Carbon (C) | 0.80 – 0.90 | Forms hard carbides with other elements, boosting wear resistance. |
| Manganese (Mn) | 0.15 – 0.40 | Improves hardenability and reduces brittleness during heat treatment. |
| Silicon (Si) | 0.15 – 0.40 | Enhances strength and resistance to oxidation at high temperatures. |
| Chromium (Cr) | 3.80 – 4.50 | Supports carbide formation and improves hardenability; boosts corrosion resistance. |
| Tungsten (W) | 5.50 – 6.75 | A key element for red hardness—retains strength at 600+ °C, critical for high-speed cutting. |
| Molybdenum (Mo) | 4.50 – 5.50 | Works with tungsten to enhance red hardness and reduce brittleness. |
| Vanadium (V) | 1.70 – 2.20 | Forms ultra-hard vanadium carbides, improving edge retention and wear resistance. |
| Cobalt (Co) | 4.50 – 5.50 | Further boosts red hardness and high-temperature stability. |
| Sulfur (S) | ≤ 0.030 | Minimized to avoid weakening the steel and reducing tool life. |
| Phosphorus (P) | ≤ 0.030 | Kept low to prevent brittleness, especially under high heat. |
1.2 Physical Properties
These properties determine how EN 1.3343 behaves during machining and tool use—like heat transfer or dimensional stability. All values are measured at room temperature unless stated:
- Density: 8.10 g/cm³ (slightly higher than standard steels, due to tungsten and cobalt content).
- Melting Point: 1420 – 1480 °C (high enough to withstand forging and heat treatment without melting).
- Thermal Conductivity: 25 W/(m·K) (lower than carbon steel, which helps retain heat in the tool edge during cutting).
- Coefficient of Thermal Expansion: 11.0 × 10⁻⁶/°C (from 20 to 600 °C; low expansion means tools keep their shape during high-speed cutting).
- Specific Heat Capacity: 450 J/(kg·K) (efficient at absorbing heat, reducing the risk of overheating during prolonged use).
1.3 Mechanical Properties
EN 1.3343’s mechanical properties are optimized for cutting tools—prioritizing hardness, edge retention, and heat resistance. Below are its typical properties after standard heat treatment (quenching + tempering):
| Property | Typical Value | Test Standard | Why It Matters |
|---|---|---|---|
| Hardness (HRC) | 63 – 66 | EN ISO 6508 | Ultra-high hardness ensures excellent edge retention (critical for milling cutters or drills). |
| Tensile Strength | ≥ 2400 MPa | EN ISO 6892 | Handles high cutting forces without breaking—ideal for machining hard materials. |
| Yield Strength | ≥ 2000 MPa | EN ISO 6892 | Resists permanent deformation, so tools keep their cutting geometry. |
| Elongation | ≤ 5% | EN ISO 6892 | Low ductility (expected for hard high speed steels; a trade-off for hardness). |
| Impact Toughness (Charpy V-notch) | ≥ 12 J (at 20 °C) | EN ISO 148-1 | Moderate toughness—avoids brittle fracture during light shock (e.g., tool loading). |
| Red Hardness | Retains 90% hardness at 600 °C | EN ISO 6508 | Lets tools cut at high speeds (30–50 m/min for steel) without softening. |
| Fatigue Strength | ~900 MPa (10⁷ cycles) | EN ISO 13003 | Resists failure from repeated cutting cycles (key for high-volume machining). |
1.4 Other Properties
- Corrosion Resistance: Moderate. Chromium content helps resist rust in workshop environments, but avoid long exposure to chemicals or moisture.
- Wear Resistance: Excellent. Tungsten, vanadium, and cobalt carbides create a hard surface that resists abrasive wear—even when machining hard materials like stainless steel or alloy steel.
- Machinability: Poor (in hardened state). It’s extremely hard to machine after heat treatment, so most shaping is done when the steel is annealed (softened to HRC 24–28).
- Hardenability: Excellent. It hardens evenly across thick sections (up to 30 mm), so large tools like gear cutting tools have consistent performance.
- High-temperature Stability: Outstanding. It maintains strength and hardness at temperatures up to 650 °C—far better than standard tool steels or carbon steel.
2. Applications of EN 1.3343 High Speed Steel
EN 1.3343’s red hardness and wear resistance make it ideal for high-speed, high-heat cutting tasks. Here are its most common uses, with real examples:
2.1 Cutting Tools
- Examples: Milling cutters, turning tools, drills, and reamers for machining metals like alloy steel, stainless steel, or cast iron.
- Why it works: Red hardness lets tools cut at high speeds without softening. A German machine shop used EN 1.3343 milling cutters for alloy steel parts—tool life increased by 200% vs. standard high speed steel (HSS).
2.2 Broaches
- Examples: Internal or external broaches for creating complex shapes (e.g., splines or keyways) in metal parts.
- Why it works: Wear resistance keeps broach teeth sharp through hundreds of cuts. A U.S. automotive supplier used EN 1.3343 broaches for gear splines—broach life jumped from 5,000 to 15,000 parts.
2.3 Gear Cutting Tools
- Examples: Hob cutters or shaping tools for manufacturing gears (automotive or industrial).
- Why it works: Precision edge retention ensures gear teeth have accurate geometry. A Japanese gear maker used EN 1.3343 hob cutters—gear quality improved (fewer surface defects) and tool changes dropped by 60%.
2.4 Machining of Hard Materials
- Examples: Tools for machining hardened steel (up to HRC 45), stainless steel, or heat-resistant alloys (e.g., Inconel).
- Why it works: Ultra-hard carbides resist wear from tough materials. A Chinese aerospace manufacturer used EN 1.3343 drills for Inconel parts—drill life increased from 20 to 80 holes per tool.
3. Manufacturing Techniques for EN 1.3343 High Speed Steel
Turning EN 1.3343 into high-performance tools requires precise, specialized steps. Here’s a step-by-step breakdown:
- Melting: Raw materials (iron, tungsten, cobalt, etc.) are melted in an electric arc furnace (EAF) or induction furnace at 1550–1650 °C. This ensures uniform mixing of high-value elements like tungsten and cobalt.
- Casting: Molten steel is poured into ingot molds (small sizes, 5–20 kg) to avoid internal defects. Slow cooling (10–20 °C/hour) prevents carbide segregation.
- Forging: Ingots are heated to 1100–1180 °C and hammered or pressed into tool blanks (e.g., 10x10x100 mm for drill bits). Forging breaks up large carbides, improving tool strength.
- Heat Treatment: The most critical step for maximizing performance:
- Annealing: Heat to 850–900 °C, hold 2–4 hours, cool slowly. Softens steel to HRC 24–28 for machining.
- Preheating: Heat to 800–850 °C, hold 1 hour. Prepares the steel for quenching.
- Austenitizing: Heat to 1200–1240 °C, hold 15–30 minutes. Critical for dissolving carbides.
- Quenching: Cool rapidly in oil or air (depending on tool size). Hardens steel to HRC 64–67.
- Tempering: Reheat to 540–580 °C, hold 1–2 hours, cool. Repeat 2–3 times. Reduces brittleness and sets final hardness (HRC 63–66).
- Machining: Most shaping (milling, drilling, grinding) is done before quenching (annealed state). Carbide tools or diamond grinders are used for post-quenching finishing.
- Grinding: Precision grinding (CNC grinders) creates sharp cutting edges and tight tolerances (±0.001 mm for drills or reamers).
- Surface Treatment (Optional):
- Coating: Add TiN (titanium nitride) or TiAlN (titanium aluminum nitride) coatings to boost wear resistance by 50–100%.
- Nitriding: Creates a hard surface layer (HRC 70+) for tools needing extra wear protection.
4. Case Study: EN 1.3343 in Milling Cutters for Hardened Steel
A European automotive parts manufacturer faced a problem: their standard HSS milling cutters were wearing out every 500 parts when machining hardened steel (HRC 40) gear hubs. They switched to EN 1.3343 cutters (coated with TiAlN), and here’s what happened:
- Process: Cutters were forged, annealed, machined to shape, heat-treated (1220 °C quenching + 560 °C tempering), ground to sharp edges, and coated with TiAlN.
- Results:
- Cutter life increased to 2,000 parts (300% improvement) thanks to EN 1.3343’s red hardness and TiAlN coating.
- Machining speed increased from 25 to 40 m/min (60% faster), reducing production time.
- Part quality improved: gear hubs had smoother surfaces (Ra 0.8 μm vs. 1.6 μm with old cutters).
- Why it worked: EN 1.3343’s tungsten and cobalt retained hardness at the high cutting temperatures (500+ °C), while the TiAlN coating reduced friction between the cutter and steel—minimizing wear.
5. EN 1.3343 vs. Other Cutting Materials
How does EN 1.3343 stack up against common alternatives? Let’s compare key properties for cutting tools:
| Material | Hardness (HRC) | Red Hardness (600 °C) | Wear Resistance | Machinability | Cost (vs. EN 1.3343) | Best For |
|---|---|---|---|---|---|---|
| EN 1.3343 High Speed Steel | 63 – 66 | Excellent | Excellent | Poor (hardened) | 100% | High-speed cutting of hard metals |
| Standard HSS (EN 1.3340) | 60 – 63 | Good | Good | Fair (hardened) | 60% | General cutting (mild steel) |
| Carbide Tools | 85 – 90 (HV) | Excellent | Very Good | Very Poor | 300% | Ultra-high-speed cutting (50+ m/min) |
| Ceramic Tools | 90 – 95 (HV) | Outstanding | Very Good | Extremely Poor | 500% | Machining super-alloys (e.g., Inconel) |
| Carbon Steel (1095) | 55 – 60 | Poor | Poor | Excellent | 20% | Low-speed cutting (soft materials) |
| Alloy Steel (4140) | 30 – 40 | Very Poor | Fair | Excellent | 30% | Non-cutting tools (e.g., tool holders) |
Key takeaway: EN 1.3343 offers the best balance of red hardness, wear resistance, and cost for high-speed cutting of hard metals. It’s cheaper than carbide or ceramic tools and more durable than standard HSS or carbon steel.
Yigu Technology’s View on EN 1.3343 High Speed Steel
At Yigu Technology, EN 1.3343 is our top choice for clients needing tools that perform in high-speed, high-heat machining. Its unique carbide blend solves the common issue of tool softening—critical for machining hard materials like stainless steel or alloy steel. We often pair it with TiAlN coatings to extend tool life further, helping clients cut costs and boost productivity. For automotive, aerospace, or industrial manufacturers, EN 1.3343 isn’t just a tool material—it’s a way to achieve consistent, high-quality results in demanding applications.
FAQ About EN 1.3343 High Speed Steel
1. Can EN 1.3343 be used for machining non-metallic materials (e.g., plastics or wood)?
While EN 1.3343 is technically capable, it’s overkill for non-metallic materials. Its high hardness and red hardness are designed for metal cutting, and using it for plastics/wood would be costly and unnecessary. For non-metals, choose standard HSS or carbon steel tools instead.
2. What’s the best coating for EN 1.3343 tools?
For most applications, TiAlN (titanium aluminum nitride) is the best choice. It resists high temperatures (up to 800 °C) and reduces friction, making it ideal for high-speed cutting of steel or stainless steel. For machining aluminum, use TiCN (titanium carbonitride) to prevent material buildup on the tool edge.
3. Is EN 1.3343 more expensive than standard HSS?
Yes, EN 1.3343 costs about 60–70% more than standard HSS (e.g., EN 1.3340) due to its cobalt and tungsten content. But it’s worth the investment: EN 1.3343 tools last 2–3x longer, reduce downtime from tool changes, and let you machine at faster speeds—saving money in the long run.
