JIS SK6M Water Hardening Tool Steel Wire

JIS SK6M Water Hardening Tool Steel Wire Product Information -:- For detailed product information, please contact sales. -: JIS SK6M Water Hardening Tool Steel Wire Synonyms -:- For detailed product information, please contact sales. -:

JIS SK6M Water Hardening Tool Steel Product Information -:- For detailed product information, please contact sales. -: ### **Product Technical Datasheet: JIS SK6M Water-Hardening Tool Steel (Mo-Modified)** --- #### **1. Product Overview** **JIS SK6M** is a medium-high-carbon, **molybdenum-modified water-hardening tool steel** specified under the Japanese Industrial Standard (JIS) G 4404. As the molybdenum-enhanced variant of the standard SK6 grade, it offers a technologically optimized balance within the water-hardening family. With a nominal carbon content of 0.70-0.80%, it is designed to provide a superior combination of **good wear resistance, enhanced hardenability, and improved toughness** compared to its plain carbon counterpart. The strategic addition of molybdenum refines the steel's microstructure, reduces the severity of required quenching, and improves performance consistency, making SK6M a reliable and cost-effective choice for more demanding tooling applications where plain carbon steels may fall short. --- #### **2. International Standard Cross-Reference** SK6M is defined under JIS G 4404 as a molybdenum-type carbon tool steel, with functional equivalents in other international systems. | Standard System | Equivalent / Similar Grade | Note | | :--- | :--- | :--- | | **JIS G 4404 (Japan)** | **SK6M** | Defining standard (Molybdenum-type) | | **ASTM (USA)** | W2-0.8C (Mo variant) | Similar medium-high carbon water-hardening grade with Mo | | **DIN (Germany)** | 1.2002 / C80W2 | Similar carbon content and quenching method | | **BS (UK)** | **BW1B (0.8C Mo-modified)** | Water-hardening grade with Mo addition | | **ISO** | ~TC80 (Modified) | Similar application scope | | **GB (China)** | **T8Mo** | Modified medium-high carbon tool steel with Mo | | **AISI/SAE (USA)** | ~1078 (Modified) | Similar base composition, often used for springs and tools | --- #### **3. Chemical Composition (Typical, weight % per JIS G 4404)** The composition is characterized by a balanced carbon content and the critical addition of Molybdenum. | Element | Carbon (C) | Silicon (Si) | Manganese (Mn) | **Molybdenum (Mo)** | Phosphorus (P) | Sulfur (S) | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | **Content (%)** | 0.70 - 0.80 | 0.10 - 0.30 | 0.30 - 0.60 | **0.10 - 0.25** | ≤ 0.030 | ≤ 0.030 | **Function of Key Elements:** * **Carbon (0.70-0.80%):** Provides the foundation for martensitic hardening, offering a balanced potential for hardness and toughness. * **Molybdenum (0.10-0.25%):** The key enhancement. It increases hardenability for deeper and more uniform hardening, refines grain size for improved toughness and fatigue resistance, and reduces the sensitivity to quench cracking. --- #### **4. Physical & Mechanical Properties** * **Density:** ~7.85 g/cm³ * **Thermal Conductivity:** Moderate. * **Machinability (Annealed State):** Good. The combination of spheroidized annealed structure and Mo addition allows for relatively good machinability for a tool steel. * **Hardenability:** **Moderate (Significantly Improved over SK6).** The Mo addition provides a deeper and more consistent hardened zone, making it suitable for sections up to approximately 25mm, depending on geometry. * **Primary Quenching Medium:** **Water, Brine, or Fast Polymer Quenchant.** The improved hardenability often allows for the use of less severe quenchants (e.g., agitated warm water or brine) compared to plain SK6, reducing distortion. * **Typical Achievable Hardness:** * **Annealed State:** ~ 170 - 207 HB * **Hardened & Tempered State:** **59 - 62 HRC** (Can achieve up to 63 HRC with optimal processing and low-temperature tempering). --- #### **5. Heat Treatment Guidelines** * **Forging:** Heat uniformly to 1050-850°C. Cool slowly in furnace or an insulating medium. * **Annealing:** Heat to 750-780°C, slow furnace cool to ~500°C. A full spheroidize anneal is recommended for best machinability and subsequent heat treatment response. * **Hardening:** 1. **Preheat:** Essential at 650-700°C. 2. **Austenitizing:** **790-820°C.** The Mo allows for good carbide solutioning at this range. 3. **Soak:** 20-30 minutes per inch of thickness. 4. **Quench:** Agitate in **water, brine, or a fast polymer solution.** For complex shapes, a fast oil quench may sometimes be used as a less severe alternative, albeit with slightly lower final hardness. * **Tempering:** **Must be performed immediately** after quenching. For maximum hardness and wear resistance, temper at **150-200°C for 1-2 hours.** For applications requiring better toughness, tempering at **250-350°C** is effective (resulting hardness ~54-59 HRC). --- #### **6. Product Applications** SK6M is employed in applications that demand a balance of hardness and toughness, often where standard SK6 might lack sufficient hardenability or shock resistance. * **Cutting Tools:** **Heavy-duty shear blades, industrial knives for cutting composite materials, band saw blades** for metal and wood, and slitter knives. * **Forming & Stamping Tools:** **Punches, dies, and forming tools** for medium-thickness materials, where improved toughness reduces chipping. * **Hand & Impact Tools:** **Cold chisels for metal, pry bars, heavy-duty screwdrivers, and wrench sockets.** * **Agricultural & Forestry Equipment:** **Chipper knives, heavy-duty mower blades, and tiller teeth.** * **Wear Parts & Machine Components:** **Guide rails, cam surfaces, pins, and bushings** subjected to sliding wear and moderate impact. * **Springs:** **High-stress flat springs and spring washers** requiring a high elastic limit and good fatigue resistance. --- #### **7. Advantages & Limitations** | Advantages | Limitations | | :--- | :--- | | • **Excellent balance of hardness and toughness** within the water-hardening family.
• **Improved hardenability and more uniform hardness profile** than SK6.
• **Better resistance to shock and chipping** due to finer grain structure from Mo.
• **Reduced risk of quench cracking and distortion**, allowing for more complex geometries.
• **Good fatigue resistance** for dynamic load applications. | • **Still requires relatively severe quenching** compared to oil-hardening steels.
• **Not suitable for very thick sections** requiring deep through-hardening.
• **Low hot hardness;** unsuitable for high-speed or hot-work applications.
• **Higher cost than plain SK6**, though still economical versus high-alloy steels. | --- #### **8. Comparative Selection Guide** * **SK6 vs. SK6M:** Choose **SK6M** for applications requiring **better consistency in hardening, higher toughness, or the ability to harden slightly thicker sections reliably.** SK6 may suffice for very simple, low-stress tools where cost is paramount. * **SK6M vs. Oil-Hardening (e.g., SKS93/O1):** SK6M can achieve a **slightly higher peak hardness**, but oil-hardening steels offer **superior dimensional control, minimal distortion, and better hardenability in complex shapes.** The choice depends on the priority: ultimate hardness (SK6M) vs. dimensional stability (Oil-hardening). * **SK6M vs. Shock-Resisting (e.g., SKS4):** For **high-impact applications**, shock-resisting steels are superior. SK6M is better suited for **applications combining wear and moderate shock.** **Conclusion:** JIS SK6M is a **highly versatile and practical grade** within the water-hardening tool steel category. The molybdenum modification successfully elevates the performance of the base SK6 composition, making it a **premium, yet cost-effective, choice for a broad range of industrial tooling and component applications.** It is particularly well-suited for tools that must withstand a combination of abrasive wear and intermittent shock loading. For tool designers and manufacturers seeking to upgrade from plain carbon steels without venturing into the realm of high-alloy grades, SK6M represents an **excellent intermediate solution** with proven reliability and performance. -:- For detailed product information, please contact sales. -: JIS SK6M Water Hardening Tool Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6795 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: JIS SK6M Water Hardening Tool Steel Properties -:- For detailed product information, please contact sales. -:

Applications of JIS SK6M Water Hardening Tool Steel Wire -:- For detailed product information, please contact sales. -: Chemical Identifiers JIS SK6M Water Hardening Tool Steel Wire -:- For detailed product information, please contact sales. -:

Packing of JIS SK6M Water Hardening Tool Steel Wire -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and Steel Wire drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3266 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition