JIS SK3 Water Hardening Tool Steel Wire

JIS SK3 Water Hardening Tool Steel Wire Product Information -:- For detailed product information, please contact sales. -: JIS SK3 Water Hardening Tool Steel Wire Synonyms -:- For detailed product information, please contact sales. -:

JIS SK3 Water Hardening Tool Steel Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: JIS SK3 Water Hardening Tool Steel** ## **Overview** **JIS SK3** is a **high-carbon, non-alloyed water-hardening tool steel** within the Japanese Industrial Standards (JIS) carbon tool steel series (SK). Positioned as a versatile, medium-high carbon grade, SK3 offers a **balanced combination of high hardness, good wear resistance, and moderate toughness** relative to the SK series. It is one of the most widely used carbon tool steels for general-purpose cutting, forming, and measuring tools where a hard, durable edge is required. Like all water-hardening steels, it features **very shallow hardenability, requires a severe water or brine quench, and has poor resistance to thermal softening**. ## **1. Chemical Composition (JIS G 4401 Standard)** SK3 has a classic high-carbon, low-alloy composition. | Element | Content (%) | Primary Function | |---------|------------|------------------| | **Carbon (C)** | **1.00 - 1.10** | **Primary element.** Provides high hardenability potential and forms cementite for hardness and wear resistance. This carbon range is optimal for a balance of hardness and toughness in carbon steels. | | **Silicon (Si)** | ≤ 0.35 | Deoxidizer, slightly strengthens ferrite. | | **Manganese (Mn)** | ≤ 0.50 | Moderately increases hardenability and combats sulfur embrittlement. | | **Phosphorus (P)** | ≤ 0.03 | Impurity, kept low. | | **Sulfur (S)** | ≤ 0.03 | Impurity, kept low. | | **Chromium (Cr)** | ≤ 0.30 | Residual, not an intentional alloy. | | **Nickel (Ni)** | ≤ 0.25 | Residual. | | **Copper (Cu)** | ≤ 0.25 | Residual. | | **Iron (Fe)** | Balance | Base metal. | **Key Chemistry Note:** SK3 is a **eutectoid to slightly hypereutectoid steel**. Its **carbon content (~1.05%)** is near the eutectoid point (0.77% C), which allows for a microstructure consisting primarily of fine pearlite or martensite upon heat treatment, without excessive networks of brittle primary cementite that plague higher-carbon grades like SK1/SK2. This results in the **best overall toughness among the high-carbon SK grades** while still achieving very high hardness (~65 HRC). The minimal alloying means its properties are almost entirely dependent on carbon content and heat treatment precision. ## **2. Physical & Mechanical Properties** *Typical properties in the hardened and tempered condition.* | Property | Typical Value / Condition | |----------|--------------------------| | **Density** | ~7.85 g/cm³ | | **Melting Point** | ~1485°C (2705°F) | | **Thermal Conductivity** | ~48 W/m·K | | **Coefficient of Thermal Expansion** | ~12.5 × 10⁻⁶/K (20-100°C) | | **Modulus of Elasticity** | 205-210 GPa | | **Annealed Hardness** | 183-217 HB | | **As-Quenched Hardness (Water)** | **Up to 64-66 HRC**. | | **Hardened & Tempered Hardness** | **58-63 HRC** (Versatile working range). | | **Tensile Strength (at 60 HRC)** | ~1850-2000 MPa (268-290 ksi) | | **Impact Toughness** | **Moderate (for a water-hardening steel).** The best in the SK1-SK3 range due to optimal carbon content and absence of coarse cementite networks. | | **Wear Resistance** | **Good.** Relies on high hardness; adequate for many general tooling applications. | | **Hardenability** | **Very Shallow.** Full hardening only to depths of **~3-5 mm (0.12-0.2 in)**. | | **Hot Hardness** | **Very Poor.** Significant softening begins above **~200-250°C (390-480°F)**. | | **Machinability (Annealed)** | **Good.** Better than SK1/SK2 due to lower carbon. | | **Grindability** | Good. | ## **3. International Standards & Cross-References** | Standard | Designation | Notes | |----------|------------|-------| | **JIS** | **SK3** (JIS G 4401) | | | **AISI (USA)** | **~W1-10** (AISI W1 with ~1.0% C) | The closest direct equivalent. | | **ISO (International)** | **~C100U** (ISO 4957) | | | **DIN (Germany)** | **~C100W2** (1.1645) | | | **BS (UK)** | **~BW1A** | | | **GB (China)** | **T10** (Carbon tool steel) | A common equivalent (T10: 0.95-1.04% C). | | **Common Name** | **1.0% Carbon Tool Steel** | | ## **4. Product Applications** SK3 is a **general-purpose carbon tool steel** used for a wide variety of tools where high hardness is needed, and the severe limitations of water hardening are acceptable. **Primary Applications:** * **Cutting Tools:** **Hand saw blades, band saw blades, metal cutting knives, shears.** * **Woodworking Tools:** **Chisels, plane blades, carving tools, drill bits.** * **Metal-Forming Tools:** **Punches, dies, bending tools** for thin sheet metal. * **Hand Tools:** **Screwdrivers, wrenches, pliers** (hardened parts). * **Measuring Tools:** **Calipers, gauges, templates, straight edges.** * **Springs** for mechanical devices. * **Agricultural and Garden Tools** (blades, cutters). **Applications to Avoid:** * Tools subject to heavy impact or shock (e.g., cold chisels for thick steel). * Complex tools with sharp internal corners or severe section changes (high cracking risk). * High-speed cutting tools that generate heat. * Tools requiring deep, uniform hardness in thick sections (>10mm). ## **5. Heat Treatment Guidelines** Heat treatment is standard for water-hardening steels but requires skill. * **Annealing:** Heat to **750-780°C (1380-1435°F)**, slow furnace cool for spheroidized structure. * **Hardening:** 1. **Preheating:** Preheat to **700-750°C (1290-1380°F)** to reduce thermal shock. 2. **Austenitizing:** Heat to **780-820°C (1435-1510°F).** A common target is **790-810°C (1455-1490°F)**. Soak for 10-20 min/inch. 3. **Quenching:** Quench **immediately in agitated water or brine.** For any non-simple shape, use an **interrupted quench**: quench to ~300-400°C, then transfer to oil or air. * **Tempering:** * **Temper immediately** (within 30-60 min). * **For cutting tools (high hardness):** Temper at **150-200°C (300-390°F)** for 1-2 hours. Target hardness: 61-63 HRC. * **For improved toughness (striking/forming tools):** Temper at **250-350°C (480-660°F)**. **Note:** Rapid cooling from this tempering range is advised to minimize tempered martensite embrittlement. Target hardness: 55-60 HRC. * **Double tempering** is recommended. ## **6. Key Advantages & Limitations** **Advantages:** * **Good balance of hardness and toughness** for a carbon tool steel. * **Lower cost** than alloy tool steels. * **Simple heat treatment principle** (though difficult in practice). * **Good machinability and grindability** in the annealed state. * **Can be re-hardened** if damaged or worn. **Severe Limitations (Inherent to Water-Hardening):** * **Very Shallow Hardenability:** Only surface hardens; thick tools have soft cores. * **High Distortion & Cracking Risk:** The water quench induces severe stresses and unpredictable size changes. * **Low Toughness (Relative):** Still brittle compared to oil- or air-hardening tool steels at the same hardness. * **Poor Thermal Stability:** Cannot be used in any application generating heat. * **Decarburization:** Easily loses surface carbon during heat treatment, requiring grinding allowance. **Modern Perspective & Alternatives:** While SK3 is still used for traditional and low-cost tools, it has been **largely superseded for industrial and precision tooling by oil- and air-hardening steels**. * **For general-purpose tooling:** **JIS SKS3 (Oil-Hardening)** or **AISI O1** offer deeper hardening, much less distortion, better toughness, and are more forgiving to heat treat. * **For better stability and wear resistance:** **JIS SKD11 (AISI D2)** or **JIS SKS93 (AISI A2)**. * SK3 remains relevant for **simple hand tools, low-volume production, or applications where its limitations are well-understood and its low cost is decisive.** **Conclusion:** JIS SK3 is a **versatile, traditional carbon tool steel** that represents a practical balance within the limitations of water-hardening technology. For makers and users who can manage its finicky heat treatment and design around its shallow hardening, it provides a hard, serviceable edge at low material cost. However, for any application requiring reliability, precision, or durability, moving to an oil- or air-hardening grade is a transformative improvement that justifies the modest increase in material cost. --- **Disclaimer:** Heat treating JIS SK3 is a **high-risk process** that requires experience to avoid cracking and excessive distortion. It is not suitable for precision tools with tight tolerances or complex geometries without specialized expertise. The steel is **not recommended for tools subject to impact or thermal exposure**. For new designs, strongly consider **oil-hardening alternatives like SKS3 (JIS) / O1 (AISI)**. The information provided assumes proper heat treatment execution; results vary widely with technique and part geometry. -:- For detailed product information, please contact sales. -: JIS SK3 Water Hardening Tool Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6788 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 SK3 Water Hardening Tool Steel Properties -:- For detailed product information, please contact sales. -:

Applications of JIS SK3 Water Hardening Tool Steel Wire -:- For detailed product information, please contact sales. -: Chemical Identifiers JIS SK3 Water Hardening Tool Steel Wire -:- For detailed product information, please contact sales. -:

Packing of JIS SK3 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 3259 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