Aobo Steel supply D3 steel for your project
Premium D3 Tool Steel Supplier for Unmatched Durability
D3 tool steel is a widely used high-carbon, high-chromium cold work tool steel. D3 is the designation under the ASTM A681 standard. Similar grades in other common standards include Germany/W-Nr. 1.2080, USA/ASTM T30403, Japan/JIS SKD1, and Czech Republic/CSN 19436. In the following article, we will use D3 tool steel as the representative name.
D3 steel exhibits high strength, good hardenability, and excellent wear resistance. It undergoes minimal distortion during quenching. However, it has poor impact toughness and is prone to brittle fracture. It quickly forms uneven eutectic carbides and has poor thermal conductivity and high-temperature plasticity.
Due to its excellent wear resistance, D3 steel is widely used in manufacturing cold stamping dies and punches, cold cutting tools, drill bushings, gauges, drawing dies, embossing dies, thread rolling plates, deep drawing dies, and thread rolling dies that require high wear resistance and are subjected to lower impact loads.
Most cost-effective, high-quality supplier of D2 steel
We offer both D2 electric furnace steel and D2 ESR steel. Considering our customers’ purchasing costs, we produce D2 round bars with diameters under 200mm using the electric furnace method, which can meet Ultrasonic testing (UT) Sep 1921-84 D/d flaw detection. Customers can purchase high-standard D2 round bars at a lower cost. We adopt the ESR process for diameters above 200mm to ensure that the internal structure can meet Ultrasonic testing (UT) Sep 1921-84 E/e flaw detection.
Excellent D2 Forged Steel Supplier
Aobo Steel has over 20 years of experience in forging D2 steel, giving us a deep practical understanding of quality control in this field. Our D2 forged steel products mainly come in round bar, plate, and block shapes. We have over 40 suppliers providing the best processing services, enabling us to offer advantages such as short lead times, stable quality, and competitive prices.
Suply Range
The shapes of steel that Aobo Steel produces include D2 tool round bars and D2 plates.
| Shape | Size | Length | Surface finish | tolerance |
| round bar | diameter 20mm-400mm | length 2500mm-5800mm | black | 0/+5mm |
| peeled | 0/+5mm | |||
| turned(machined) | 0/+2mm | |||
| plate | width*thickness 100mm-800mm*10mm-400mm | length 2500mm-5800mm | black | 0/+5mm |
| peeled | 0/+5mm | |||
| turned(machined) | 0/+2mm |
D3 tool steel equivalent grades and chemical composition under different standards
| Standard | Grade | C (%) | Si (%) | Mn (%) | Cr (%) | P (%) | S (%) |
| ASTM A681-2015 | D3/T30403 | 2.00-2.35 | ≤0.60 | ≤0.60 | 11.00-13.50 | ≤0.030 | ≤0.030 |
| EN ISO 4957:2017 | X210Cr12/1.2080 | 2.00-2.30 | ≤1.00 | ≤1.00 | 11.00-13.00 | ≤0.030 | ≤0.030 |
| JIS G4404:2015 | SKD1 | 1.90-2.20 | ≤0.40 | ≤0.40 | 11.00-13.00 | ≤0.030 | ≤0.030 |
| ISO 4957:2018 | X210Cr12 | 2.00-2.30 | ≤1.00 | ≤1.00 | 11.00-13.00 | ≤0.030 | ≤0.030 |
| GB/T 1299-2014 | Cr12/T21200 | 2.00-2.30 | ≤0.40 | ≤0.40 | 11.50-13.00 | ≤0.030 | ≤0.020 |
D3 Heat treatment
1. Preheating Treatment Process Specifications
| Process Parameters | |
|---|---|
| General Annealing After Forging | Heating temperature: 850 ~ 870°C, holding time: 4 ~ 5h, cooling rate: <30°C/h, furnace cooling to below 500°C, air cooling after furnace, hardness after annealing: ≤229HBW, microstructure after annealing: granular pearlite + carbides |
| Isothermal Annealing After Forging | Heating temperature: 830 ~ 850°C, holding time: 2 ~ 3h, furnace cooling to 720 ~ 740°C, holding time: 3 ~ 4h, furnace cooling to below 550°C, air cooling after furnace, hardness after annealing: ≤269HBW, microstructure after annealing: granular pearlite + carbides |
2. Quenching
a)Recommended Quenching Specifications
| Process | Quenching Temperature (°C) | Cooling Method | Hardness HRC |
|---|---|---|---|
| Recommended Quenching Specifications | 950 ~ 980 | Oil Cooling | ≥60 |
b)Performance Comparison under Different Heat Treatment Processes
| Heat Treatment Process | Hardness (HRC) | Impact Toughness a_k’ (J/cm²) | Retained Austenite (Volume Fraction, %) | Die Life (×10⁵ pieces) | Wear Amount (mg) |
|---|---|---|---|---|---|
| 980°C Heating, Oil Quenching | 66.5 | 14.1 | 13.2 | 4 | — |
| 980°C Heating, 180°C Tempering 50 min | 65.8 | 15.8 | — | 5 | — |
| 980°C Heating, 270°C Tempering 3h | 65.5 | 15.9 | — | 6 | 11.9 |
| 980°C Heating, 270°C Tempering 4h | 60 | 17.7 | 15.02 | — | — |
| 980°C Heating, 270°C Tempering 5h | 59 | 16.8 | — | — | — |
| 980°C Heating, 180°C Pre-tempering 35 min, 270°C Tempering 3h | 64.6 | 14.6 | — | 12-15 | 8.2 |
| 980°C Heating, 180°C Pre-tempering 35 min, 270°C Tempering 4h | 46.2 | 14.9 | — | 12-28 | — |
| 980°C Heating, 180°C Pre-tempering 35 min, 270°C Tempering 3h (Repeated) | 63.8 | 15.2 | — | — | — |
c)Relationship between Quenching Temperature and Hardness
| Quenching Temperature (°C) | Hardness (HRC) |
|---|---|
| 875 | 54.5 |
| 900 | 57 |
| 925 | 60 |
| 950 | 62.5 |
| 975 | 65 |
| 1000 | 66 |
| 1050 | 64 |
| 1100 | 59.5 |
3. Tempering
a)Recommended Tempering Process Specifications
| Purpose of Tempering | Heating Temperature (°C) | Tempering Time (hours) | Number of Tempering Cycles | Hardness (HRC) |
|---|---|---|---|---|
| Relieve stress, stabilize structure | 180 ~ 200 | 2 | 1 | 60 ~ 62 |
| Relieve stress, reduce hardness | 320 ~ 350 | 2 | 1 | 57 ~ 58 |
b)Relationship between Tempering Temperature and Hardness
| Tempering Temperature (°C) | Not Tempered | 200 | 300 | 400 | 450 | 500 | 550 | 600 | 650 |
|---|---|---|---|---|---|---|---|---|---|
| Hardness (HRC) | 65 | 63 | 62 | 60 | 60 | 60 | 59.5 | 57.1 | 44 |
D3 steel Applications
D3 tool steel is excellent for jobs requiring strong wear resistance and hardness. It works well in harsh, abrasive conditions. Some of its typical applications include:
- Blanking and Punching Dies: D3 steel makes tools subject to high stress and wear, including blanking dies, punching dies, and forming dies.
- Shear Blades: High hardness and toughness make it suitable for shearing softer metals.
- Rolls and Slitting Tools: D3 steel is frequently used where high wear resistance is crucial in rolling and slitting operations.
- Cold Work Tooling: D3 tool steel is used for tools used in heavy cold working processes, such as hobbing dies and forging dies.
Why should you choose Aobo Steel as your tool steel supplier?
At Aobo Steel, we pride ourselves on our exceptional supply capacity and dedication to meeting customer demands. Our monthly shipments exceed 1,500 tons in the Chinese market, reflecting our robust production and delivery capabilities. With a strong network of over 40 trusted suppliers, we ensure a steady supply of high-quality tool steels to meet various industry needs.
To provide even greater flexibility, we maintain stock for select products, allowing us to fulfill urgent orders quickly. Additionally, we specialize in fully customizable solutions, tailoring our products to your exact specifications for optimal application performance.
Our strategic location near the Yangtze River gives us a significant advantage in export logistics, enabling fast and cost-effective shipping to customers worldwide. Whether you need standard products or custom orders, Aobo Steel is committed to delivering reliability, quality, and service excellence.
At Aobo Steel, quality control is at the heart of our operations. Our dedicated testing team with over 20 years of experience ensures every product meets the highest standards before leaving our facility. Our comprehensive quality assurance process includes chemical composition analysis, metallographic examination, hardness testing, physical performance evaluation, and ultrasonic testing (UT) to detect internal defects.
To guarantee reliability, we perform 100% quality inspection on all products before shipment, ensuring they meet the required specifications and industry standards. Additionally, we support third-party inspections upon request to provide our customers with extra confidence in the quality of our materials. With this rigorous approach, Aobo Steel consistently delivers tool steels that offer superior performance and dependability in various applications.
At Aobo Steel, our service capacity is designed to meet diverse customer needs efficiently and precisely. We provide fully customizable products, offering surface treatments, descaling, and custom-length cutting options to suit specific requirements. Our experienced foreign trade team is well-versed in handling international orders, ensuring smooth communication and seamless transactions.
To provide the best service, we guarantee a 24-hour rapid response to all inquiries, allowing us to address your needs promptly and effectively. At Aobo Steel, we are committed to delivering high-quality tool steels and exceptional customer service to support your success.
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