NSPM8407 4Cr5MoSiV1 SKD61 hot work tool steel
8407 tool steel offers excellent hot toughness, polishability, and resistance to thermal fatigue, making it a reliable choice for hot extrusion dies and mandrels, forging dies, and die-casting moulds.
- Standard: Ningshing NSPM8407, GB 4Cr5MoSiV1, US H13, JIS SKD61
- Technique: Vacuum refining + Electroslag remelting (ESR) + Special forging process + Ultrafine treatment. Ensures high purity, uniform microstructure, and high isotropy.
- Shape: Round , Blocks
- Heat treatment: Annealing: 860–880 °C, hold 3–4 h, air cool below 500 °C → hardness ≤ 229 HBS (microstructure: spheroidized pearlite + minor carbides). Quenching: 1020–1050 °C, oil or air (media 20–60 °C), cool to room temperature → hardness 56–58 HRC. Tempering: 540–600 °C, air furnace, air cool → hardness 45–50 HRC.
- Surface Treatment: Delivered in spheroidized annealed condition (asforged / black surface).
- Tolerance: According to Ningshing’s standard supply specification
- MOQ: 1 Ton
We supply NSPM 8407 in various custom sizes
plate
flat
block
round
Chemical Composition (%)
钢种 | C | Si | Mn | Cr | Mo | V | P | S |
NSPM8407 (Ningshing) | 0.37 | 0.95 | 0.30 | 5.10 | 1.40 | 0.90 | ≤0.015 | ≤0.005 |
4Cr5MoSiV1 (GB/T 1299) | 0.32~0.45 | 0.80~1.20 | 0.20~0.50 | 4.75~5.50 | 1.10~1.75 | 0.80~1.20 | ≤0.030 | ≤0.030 |
H13 (AISI) | 0.32~0.45 | 0.80~1.20 | 0.20~0.50 | 4.75~5.50 | 1.10~1.75 | 0.80~1.20 | ≤0.030 | ≤0.030 |
1.2344 (DIN) | 0.38 | 1.0 | 0.4 | 5.0 | 1.3 | 1.0 | — | — |
SKD61 (JIS) | 0.39 | 0.90~1.00 | 0.40 | 5.15~5.30 | 1.20~1.40 | 0.80 | — | — |
Main characteristics of 8407 tool steel
- Superior Hot Toughness – Resists chipping and brittle fracture at elevated temperatures
- Excellent Polishability – Supports high-gloss cavity surface finishes
- Outstanding Thermal-Fatigue Resistance – Reduces heat checking under repeated thermal cycling
- Reliable Hot-Work Performance – Suitable for a wide range of hot-forming applications
8407 tool steel applications
8407 steel for Hot Extrusion Dies & Mandrels
Exceptional hot hardness and resistance to thermal softening keep NSPM8407 dies and mandrels dimensionally stable under sustained high-temperature extrusion of aluminum and copper alloys, ensuring long tool life.
8407 steel for Forging Dies (hammer, press, precision)
Superior toughness combined with excellent heat-checking resistance enables NSPM8407 to withstand the severe shock and thermal cycling of hammer, press, and precision forging operations, reducing premature failure.
8407 steel for Die-Casting Moulds (Al, Cu alloys)
High temper resistance and good thermal conductivity provide reliable performance in aluminum and copper alloy die-casting, balancing resistance to soldering, erosion, and thermal fatigue for extended die life.
Our Production Technology For NSPM8407 (4Cr5MoSiV1 / H13 / 1.2344 / SKD61) Premium Hot Work Tool Steel
- EAF
- LF
- VD
- ESR
- Special Forging Process
- Ultra-Fine Grain Treatment
- Spheroidizing Annealed
- Machined surface / Peeled
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Quality Control:
Ultrasonic testing (UT) as per SEP 1921 or ASTM A388 (upon request)
Micro Cleanliness as per ASTM E45 — ultralow inclusion levels (P ≤ 0.015%, S ≤ 0.005%)
Grain size ultra-fine, homogeneous structure - Delivery condition: Spheroidized annealed, hardness ≤ 235 HB
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Product forms:
Forged blocks: 60 – 500 × 300 – 1200 mm
Round bars: Φ60 – 600 mm
mechanical properties & heat treatment of 8407 steel
| Heat temperature | Start forging temperature | Finish forging temperature | Cooling method |
| 1100 – 1150 °C | 1100 – 1050 °C | ≥ 900 °C | Pit, sand, or furnace cooling |
Spheroidizing Annealing
- Spheroidizing annealing is performed to produce a fine, uniform spheroidized carbide microstructure (spheroidized pearlite + small amount of carbides) for optimum machinability and to prepare the steel for final hardening.
- Annealing temperature 860 – 880°C
- Holding time 3 – 4 hours
- Cooling rate 20°C/h (controlled furnace cooling)
- Cooling method Furnace cool to below 500°C, then air cool to room temperature
- Hardness after annealing ≤ 229 HB
- Microstructure Spheroidized pearlite + small amount of carbides
Hardening
- NSPM8407 is an airhardening hot work tool steel — the most widely used hot work tool steel globally. Proper preheating and austenitizing are critical to achieve the desired hardness without cracking. The steel can be quenched in oil or air, providing flexibility for distortion control.
- Pre-heating (recommended) 600 – 850°C (twostage preheat recommended to reduce thermal stress)
- Austenitizing temperature 1020 – 1050°C
- Holding time 15 – 30 minutes after temperature equalization
- Quenching media Oil (preferred) or Air
- Cooling medium temperature 20 – 60°C
- Cool to Room temperature
- Hardness after quenching 56 – 58 HRC
Stress relieving
- Perform after rough machining, heavy stock removal, or EDM to reduce residual stresses
- Heat carefully to 600 – 650°C
- Hold at temperature for 1 – 2 hours (minimum)
- Air cool after holding
- This operation reduces the risk of distortion during final hardening and improves dimensional stability
Tempering
- Temper immediately after the workpiece cools to handwarm temperature (approx. 50–70°C). Delayed tempering may cause cracking
- Number of tempers: Minimum 2 times. Double tempering is mandatory for this grade to ensure complete transformation of retained austenite and optimal property stability
- Holding time: 2 hours minimum per cycle (or 1 hour per 20mm of section thickness)
- Cooling method: Air cool after each tempering cycle
- Tempering temperature range: 560 – 620°C
- Avoid the range 425 – 550°C to prevent temper embrittlement
Why Choose NSPM as Your 8407 Tool Steel Supplier
Source Direct
Direct mill cooperation ensures stable supply, competitive pricing, and consistent quality. Global resource integration and strong supply chain management guarantee reliable material sourcing and long-term availability.
Stock Ready
50,000+ tons inventory across 11 warehouses enables fast delivery. Flexible cutting, short lead times, and ready stock support urgent demands and improve customers’ production efficiency.
Expert Team
600+ professionals, including R&D specialists and technical engineers, provide application-driven support. Fast response and deep tooling knowledge ensure accurate solutions for diverse industrial needs.
Fully Inspected
Strict quality control system with full traceability, UT testing, and heat treatment records. Certified standards (ISO, CE) ensure every material meets high-performance and reliability requirements.
Full-Chain Machining
From steel supply to precision machining, heat treatment, and equipment manufacturing, NSPM offers integrated solutions that enhance accuracy, efficiency, and overall tooling performance.
