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E: enquiry@qilumetal.com
E: enquiry@qilumetal.com
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1.2842 is a widely recognized cold work tool steel that conforms to the German standard DIN 17350. It is known for its high wear resistance, good toughness, and excellent dimensional stability after heat treatment. Due to its reliable performance in demanding applications, many countries have established equivalent grades for 1.2842, such as: O2 from American standard ASTM A681, 90MnCrV8 from European standard EN ISO 4957, 9Mn2V from Chinese standard GB/T 1299.
1.2842 steel contains manganese and chromium, which enhance its hardness and wear resistance, while a small amount of vanadium refines the grain structure, improving toughness. The moderate carbon content ensures a good balance between machinability and hardness, making it suitable for blanking dies, forming tools, and precision cutting applications.
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AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is a globally recognized cold work tool steel, designed for high-performance applications requiring exceptional wear resistance, reliable toughness, and stable dimensional accuracy after heat treatment. Compliant with international standards—including the U.S. ASTM A681 (for AISI O2), German DIN 17350 (for DIN 1.2842), and European EN ISO 4957 (for ISO 90MnCrV8)—this steel grade has become a staple in precision manufacturing due to its balanced mechanical properties and broad adaptability. It also has a well-established Chinese equivalent, 9Mn2V (per GB/T 1299), making it accessible for global supply chains.
Produced by Hunan Qilu Steel Co., Ltd., a leading manufacturer of engineering and tool steels, this cold work tool steel is supplied in a full range of forms to meet diverse industry needs, including hot-rolled bars, hot-forged bars, hot-rolled plates, and hot-forged blocks. The core advantage of AISI O2 / DIN 1.2842 / ISO 90MnCrV8 lies in its chemical composition: a controlled carbon content (0.85-0.95%) balances machinability and post-heat-treatment hardness, while manganese (1.40-2.20%, varying by standard) and chromium (0.20-0.50%) enhance surface hardness and wear resistance. A small addition of vanadium (0.05-0.30%) refines the grain structure, significantly improving toughness—a critical attribute for tools subjected to repeated impact or stress during cold working processes.
Whether used in stamping dies for thin metal sheets, precision cutting tools, or wear-resistant mechanical components, AISI O2 / DIN 1.2842 / ISO 90MnCrV8 consistently delivers predictable performance, reducing downtime and ensuring long tool life. Its compatibility with standard heat treatment protocols further simplifies integration into existing manufacturing workflows, making it a preferred choice for both small-scale workshops and large industrial facilities.
The tailored chemical makeup of AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is the foundation of its superior performance, with each element serving a specific purpose to optimize functionality. Below is a breakdown of key components (all values are weight percentages, with maximum limits noted as "Max"):
Carbon (C): 0.85-0.95%: Provides the base for hardness development during heat treatment, ensuring the steel can achieve high surface hardness without sacrificing too much ductility.
Silicon (Si): 0.10-0.50% Max: Acts as a deoxidizer during steelmaking, improving purity, while also enhancing strength and resistance to oxidation at moderate temperatures.
Manganese (Mn): 1.40-2.20%: Varies slightly by standard—AISI O2 ranges from 1.40-1.80%, DIN 1.2842 from 1.90-2.10%, and ISO 90MnCrV8 from 1.80-2.20%. Manganese boosts hardenability, allowing the steel to achieve uniform hardness across thick sections, and reinforces wear resistance.
Phosphorus (P) & Sulfur (S): 0.030% Max Each: Strictly controlled to minimize brittleness and improve machinability, ensuring the steel can be easily shaped into complex tool geometries without cracking.
Chromium (Cr): 0.20-0.50%: Enhances corrosion resistance (moderate, suitable for dry or lightly lubricated environments) and forms hard carbides, further elevating wear resistance.
Vanadium (V): 0.05-0.30%: Refines the grain structure during solidification and heat treatment, which improves toughness and reduces dimensional distortion—critical for precision tools that require tight tolerances.
This composition ensures the steel avoids common trade-offs (e.g., high wear resistance at the cost of brittleness) and performs reliably in demanding cold work applications.
AISI O2 / DIN 1.2842 / ISO 90MnCrV8 responds exceptionally well to heat treatment, with clear protocols to achieve desired hardness and toughness. Key heat treatment results and parameters are as follows:
Annealed Condition (+A): Heated to 780-820℃ and slowly cooled in the furnace, this process softens the steel for machining. The resulting hardness is HB229 Max, making it easy to mill, drill, or grind into tool blanks.
Cold-Drawn Condition: For applications requiring improved surface finish and dimensional precision, cold-drawn bars have a maximum hardness of HB241 Max, eliminating the need for post-drawing annealing in many cases.
Hardening & Tempering (+HT): The most critical process for cold work tools. Preheat to 649℃ to reduce thermal shock, then heat to 780-800℃ in a salt bath furnace (optimal for uniform heating). Quench in oil to achieve rapid cooling, then temper at 170-190℃ (air-cooled) to relieve internal stresses. The final hardness reaches HRC60 Min—sufficient for cutting and stamping thin metals, plastics, and paper.
Ultrasonic Testing: To ensure internal quality, all batches undergo ultrasonic testing per EN10228-3 Class III or Sep 1921-84 D/D standards, detecting hidden defects (e.g., cracks, inclusions) that could compromise tool performance.
Heating times are also standardized: for test pieces in a salt bath, cold work steels require 25±1 minutes of hardening time and 60 minutes of tempering time. Thicker tools (over 50mm) need extended heating to ensure uniform temperature penetration.
One of the most valued features of AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is its minimal dimensional distortion after heat treatment, thanks to vanadium grain refinement. This stability is paired with flexible surface finish options to meet specific application needs:
Surface Finishes: Available in turned (+0/+3mm tolerance), milled (+0/+3mm tolerance), ground (+0/+0.05mm tolerance—best for precision tools), polished (+0/+0.05mm tolerance), peeled (+0/+0.1mm tolerance), black forged (+0/+5mm tolerance), and black rolled (+0/+1mm tolerance). Ground and polished finishes are ideal for tools requiring tight fits, such as guide bushings or measuring gauges.
Straightness: Hot-rolled and cold-drawn bars have a maximum straightness of 1mm/1000mm, while black forged products have a maximum of 3mm/1000mm—reducing the need for post-processing to correct warping.
This combination of stability and surface quality ensures tools made from this steel maintain accuracy over long production runs.
Hunan Qilu Steel offers a wide range of sizes for AISI O2 / DIN 1.2842 / ISO 90MnCrV8, with both standard stock and custom-forged options to minimize lead times:
Hot-Rolled Bars: Diameter range Φ10-Φ190mm, length 2000-5800mm (stock diameters include 12mm, 15mm, 18mm, ..., 190mm for immediate delivery).
Hot-Forged Bars: Diameter range Φ200-Φ600mm, length 2000-5800mm (custom diameters available for large-scale orders).
Hot-Rolled Plates/Sheets: Thickness 6-80mm, width 310-810mm, length 2000-5800mm (stock thicknesses: 6mm, 8mm, 10mm, ..., 80mm).
Hot-Forged Blocks: Thickness 260-500mm, width 300-1000mm, length 2000-5800mm.
Stock levels update daily, so customers are advised to contact Hunan Qilu Steel’s sales team for real-time availability.
AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is most widely used in cold work tooling, where its wear resistance and toughness excel. Key applications include:
Stamping Tooling: Ideal for stamping thin sheets (thickness <3mm) of low-carbon steel, copper alloys, and aluminum. Common end products include electronic device casings (e.g., smartphone backplates), hardware fasteners (e.g., screws, washers), and automotive interior components (e.g., dashboard clips). The steel’s high hardness (HRC60 Min) ensures the stamping die retains its sharp edges through thousands of cycles.
Forming Dies: Used for bending, deep drawing, and embossing operations. For example, it is employed in making aluminum cans (deep drawing), stainless steel sinks (bending), and metal nameplates (embossing). Its dimensional stability prevents die warping, ensuring consistent part geometry.
Shearing Tools: Suitable for precision shearing of paper, plastic films, and thin metal sheets (up to 3mm thick). Applications include paper cutting blades for printing presses, plastic sheet cutters for packaging machinery, and metal trim shears for electronics manufacturing. The steel’s wear resistance reduces blade sharpening frequency, lowering maintenance costs.
The balanced hardness and toughness of AISI O2 / DIN 1.2842 / ISO 90MnCrV8 make it an excellent choice for cutting and measuring tools that require both sharpness and durability:
Cutting Tools: Taps (for threading metal), drills (for small-diameter holes in steel), and woodworking chisels. For instance, taps made from this steel can thread low-carbon steel components without fracturing, while woodworking chisels retain their edge longer than those made from lower-grade steels.
Measuring Tools: Wear-resistant gauges such as plug gauges (for checking hole diameters) and snap gauges (for checking shaft diameters). These tools must maintain precise dimensions over time, and the steel’s dimensional stability and corrosion resistance (from chromium) ensure long-term accuracy, even in workshop environments.
Beyond tooling, AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is used in mechanical parts subjected to constant friction:
Guide Bushings: Found in machining centers and injection molding machines, these components guide moving parts (e.g., drill bits, ejector pins) and require high wear resistance. The steel’s hardness prevents premature wear, ensuring smooth operation.
Bearing Cages: Used in small to medium-sized bearings for industrial motors. The steel’s toughness absorbs minor impacts, while its wear resistance extends bearing life.
Textile Machinery Parts: Wear-resistant guide needles for weaving machines. These needles guide yarn through the weaving process and are exposed to constant friction; the steel’s durability reduces needle replacement frequency, minimizing production downtime.
DIN 1.2842 has well-recognized equivalents in major global standards, ensuring compatibility across international supply chains:
U.S. Standard (ASTM A681): AISI O2
European Standard (EN ISO 4957): ISO 90MnCrV8
Chinese Standard (GB/T 1299): 9Mn2V
These equivalents have similar chemical compositions and mechanical properties, so they can be used interchangeably in most cold work applications. For example, AISI O2 can replace DIN 1.2842 in stamping dies without modifying heat treatment or machining processes.
The optimal heat treatment process for AISI O2 steel (to achieve maximum hardness and toughness) is as follows:
Preheating: Heat the steel to 649℃ and hold for 15-20 minutes (adjust based on part thickness) to reduce thermal stress during subsequent heating.
Hardening: Transfer to a salt bath furnace and heat to 780-800℃. Hold for 25±1 minutes (for test pieces; thicker parts require longer holding times, e.g., +5 minutes for every 25mm of thickness).
Quenching: Rapidly cool the steel in mineral oil to room temperature. This step is critical for achieving martensitic structure (the source of high hardness).
Tempering: Reheat the quenched steel to 170-190℃ in a furnace and hold for 60 minutes. Air-cool to room temperature to relieve internal stresses and stabilize dimensions.
Avoid over-tempering (temperatures above 200℃), as this will reduce hardness below the HRC60 Min threshold.
ISO 90MnCrV8 steel balances wear resistance and toughness through its carefully designed composition:
Wear Resistance: Manganese (1.80-2.20%) and chromium (0.20-0.50%) form hard carbide particles in the steel matrix, which resist abrasion during cold working. This makes it suitable for tools that contact hard materials (e.g., steel sheets) repeatedly.
Toughness: Vanadium (0.05-0.20%) refines the grain structure, making the steel less brittle than high-carbon, high-chromium steels (e.g., AISI D2). This toughness allows ISO 90MnCrV8 tools to withstand minor impacts (e.g., accidental contact between the die and a misaligned part) without cracking.
In practical testing, ISO 90MnCrV8 stamping dies last 20-30% longer than dies made from lower-grade cold work steels (e.g., AISI W1), while maintaining better part quality.
Hunan Qilu Steel offers a comprehensive range of sizes for DIN 1.2842, including standard stock and custom options:
Hot-Rolled Bars: Diameter Φ10-Φ190mm, length 2000-5800mm (stock diameters: 12, 15, 18, 20, 22, 25, 28, 30, 32, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190mm).
Hot-Forged Bars: Diameter Φ200-Φ600mm, length 2000-5800mm (custom diameters available for orders over 500kg).
Hot-Rolled Plates: Thickness 6-80mm, width 310-810mm, length 2000-5800mm (stock thicknesses: 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80mm).
Hot-Forged Blocks: Thickness 260-500mm, width 300-1000mm, length 2000-5800mm.
Stock levels change daily, so contact Hunan Qilu Steel via email (enquiry@qilumetal.com) or phone (+86-0731-85185770) for real-time availability.
Yes, all batches of AISI O2 cold work tool steel from Hunan Qilu Steel undergo ultrasonic testing to ensure internal quality. The testing follows either EN10228-3 Class III (European standard) or Sep 1921-84 D/D (German standard), both of which require detecting internal defects (e.g., cracks, inclusions, voids) larger than 1mm in diameter.
Ultrasonic testing is critical for high-stress applications (e.g., stamping dies, cutting tools), as hidden defects can cause sudden tool failure during operation. Customers can request a copy of the ultrasonic test report for each order to verify quality.
1: Steel equivalent
Country | USA | ISO | Germany | China |
Standard | ASTM A681 | ISO 4957 | DIN17350 | GB/T1299 |
Grade | O2 | 90MnCrV8 | 1.2842 | 9Mn2V |
2: Chemical composition
Grade | C | Si | Mn | P | S | Cr | Mo | V |
O2 | 0.85-0.95 | 0.50Max | 1.40-1.80 | 0.030Max | 0.030Max | 0.50Max | 0.30Max | 0.30Max |
90MnCrV8 | 0.85-0.95 | 0.10-0.40 | 1.80-2.20 | 0.030Max | 0.030Max | 0.2-0.5 | / | 0.05-0.20 |
1.2842 | 0.85-0.95 | 0.10-0.40 | 1.90-2.10 | 0.030Max | 0.030Max | 0.2-0.5 | / | 0.05-0.15 |
9Mn2V | 0.85-0.95 | 0.8-1.2 | 1.70-2.00 | 0.030Max | 0.030Max | / | / | 0.10-0.25 |
3: Surface hardness and hardenability.
Heat Treatment | Hardness |
Annealed (+A) | HB229Max |
Cold-drawn condition | HB241Max |
Hardening and Tempering (+HT) | HRC60 Min |
4: Supply size & Tolerance & Stock size
Product type | Size range | Length |
Hot rolled bar | Φ10-Φ190mm | 2000-5800mm |
Hot forged bar | Φ200-Φ600mm | 2000-5800mm |
Hot rolled plate/sheet | T:6-80mm; W:310-810mm | 2000-5800mm |
Hot forged plate | T:70-250mm; W:310-810mm | 2000-5800mm |
Hot Forged block | T: 260-500mm; W: 300-1000mm | 2000-5800mm |
Surface Finish | Turned | Milled | Grinding(Best) | Polished(Best) | Peeled(Best) | Black Forged | Black Rolled |
Tolerance | +0/+3mm | +0/+3mm | +0/+0.05mm | +0/+0.05mm | +0/+0.1mm | +0/+5mm | +0/+1mm |
Straighness | 1mm/1000mm max. | 3mm/1000mm max. | |||||
Qilu steel stock hot rolled bar and hot rolled plate, below our our stock size.
1): Stock diameter for hot rolled bar
12 | 15 | 18 | 20 | 22 | 25 | 28 | 30 | 32 | 35 | 40 | 45 | 50 | 55 | 60 |
65 | 70 | 75 | 80 | 85 | 90 | 95 | 100 | 110 | 120 | 130 | 140 | 150 | 160 | 170 |
180 | 190 | 200 |
2) : Stock thickness for hot rolled plate
6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 25 | 30 |
35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 |
Since the stocks change everyday, if you want to know our stock available information, please contact our salesman.
5: Ultrasonic Test
EN10228-3 class III or Sep 1921-84 D/D
6：Steel making & Forging processing
1): Steel making process:
EF+LF+VD
EAF+LF+VD
EF+LF+VD+ESR
EAF+LF+VD+ESR
2): Forging processing:
Put the 1.2842 ingot into the furnace and pre-heat to 650-750℃
Continue heating the ingot to initial temperature: 1050-1100℃
Forge the ingot, forging temperature should be not less than 800-850℃
Cooling in the furnace or in the ash after forging
7: Heat treatment
1): Annealed:
Heat 1.2842 steel to 780-820℃ in the furnace
Soak at this temperature in the furnace
Cooling in the furnace slowly
2): Quenching and tempering:
Preheat Temperature: 649℃
Heat 1.2842 steel to 780-800℃ in the salt bath furnace
Soak at this temperature in the furnace
Quench in oil
Temper steel at 170-190℃ in the furnace
Take out from furnace and cool in the air.
Above curve in figure is just a rough guide to the tempering behaviour of steels. When applying the curves for an estimation of the hardness which can be expected in quenched and tempered tools, it should be taken into account that the optimum heat-treatment conditions for the tools are not necessarily identical with those specified for the test pieces.
The heating time of test pieces in a salt batch shall be as give in below table:
Total heating time of test pieces in a salt bath
Nature of steel | Hardening Time min | Tempering Time min |
Cold or hot work steels | 25 +/- 1 | 60 |
High-speed steels | 3 | Minimum 2 periods of 60 each |
If the test pieces are not heated in a salt batch, the heating time must be extended accordingly, and the times for heating give above are not valid for thicker tools.
AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is a globally recognized cold work tool steel, designed for high-performance applications requiring exceptional wear resistance, reliable toughness, and stable dimensional accuracy after heat treatment. Compliant with international standards—including the U.S. ASTM A681 (for AISI O2), German DIN 17350 (for DIN 1.2842), and European EN ISO 4957 (for ISO 90MnCrV8)—this steel grade has become a staple in precision manufacturing due to its balanced mechanical properties and broad adaptability. It also has a well-established Chinese equivalent, 9Mn2V (per GB/T 1299), making it accessible for global supply chains.
Produced by Hunan Qilu Steel Co., Ltd., a leading manufacturer of engineering and tool steels, this cold work tool steel is supplied in a full range of forms to meet diverse industry needs, including hot-rolled bars, hot-forged bars, hot-rolled plates, and hot-forged blocks. The core advantage of AISI O2 / DIN 1.2842 / ISO 90MnCrV8 lies in its chemical composition: a controlled carbon content (0.85-0.95%) balances machinability and post-heat-treatment hardness, while manganese (1.40-2.20%, varying by standard) and chromium (0.20-0.50%) enhance surface hardness and wear resistance. A small addition of vanadium (0.05-0.30%) refines the grain structure, significantly improving toughness—a critical attribute for tools subjected to repeated impact or stress during cold working processes.
Whether used in stamping dies for thin metal sheets, precision cutting tools, or wear-resistant mechanical components, AISI O2 / DIN 1.2842 / ISO 90MnCrV8 consistently delivers predictable performance, reducing downtime and ensuring long tool life. Its compatibility with standard heat treatment protocols further simplifies integration into existing manufacturing workflows, making it a preferred choice for both small-scale workshops and large industrial facilities.
The tailored chemical makeup of AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is the foundation of its superior performance, with each element serving a specific purpose to optimize functionality. Below is a breakdown of key components (all values are weight percentages, with maximum limits noted as "Max"):
Carbon (C): 0.85-0.95%: Provides the base for hardness development during heat treatment, ensuring the steel can achieve high surface hardness without sacrificing too much ductility.
Silicon (Si): 0.10-0.50% Max: Acts as a deoxidizer during steelmaking, improving purity, while also enhancing strength and resistance to oxidation at moderate temperatures.
Manganese (Mn): 1.40-2.20%: Varies slightly by standard—AISI O2 ranges from 1.40-1.80%, DIN 1.2842 from 1.90-2.10%, and ISO 90MnCrV8 from 1.80-2.20%. Manganese boosts hardenability, allowing the steel to achieve uniform hardness across thick sections, and reinforces wear resistance.
Phosphorus (P) & Sulfur (S): 0.030% Max Each: Strictly controlled to minimize brittleness and improve machinability, ensuring the steel can be easily shaped into complex tool geometries without cracking.
Chromium (Cr): 0.20-0.50%: Enhances corrosion resistance (moderate, suitable for dry or lightly lubricated environments) and forms hard carbides, further elevating wear resistance.
Vanadium (V): 0.05-0.30%: Refines the grain structure during solidification and heat treatment, which improves toughness and reduces dimensional distortion—critical for precision tools that require tight tolerances.
This composition ensures the steel avoids common trade-offs (e.g., high wear resistance at the cost of brittleness) and performs reliably in demanding cold work applications.
AISI O2 / DIN 1.2842 / ISO 90MnCrV8 responds exceptionally well to heat treatment, with clear protocols to achieve desired hardness and toughness. Key heat treatment results and parameters are as follows:
Annealed Condition (+A): Heated to 780-820℃ and slowly cooled in the furnace, this process softens the steel for machining. The resulting hardness is HB229 Max, making it easy to mill, drill, or grind into tool blanks.
Cold-Drawn Condition: For applications requiring improved surface finish and dimensional precision, cold-drawn bars have a maximum hardness of HB241 Max, eliminating the need for post-drawing annealing in many cases.
Hardening & Tempering (+HT): The most critical process for cold work tools. Preheat to 649℃ to reduce thermal shock, then heat to 780-800℃ in a salt bath furnace (optimal for uniform heating). Quench in oil to achieve rapid cooling, then temper at 170-190℃ (air-cooled) to relieve internal stresses. The final hardness reaches HRC60 Min—sufficient for cutting and stamping thin metals, plastics, and paper.
Ultrasonic Testing: To ensure internal quality, all batches undergo ultrasonic testing per EN10228-3 Class III or Sep 1921-84 D/D standards, detecting hidden defects (e.g., cracks, inclusions) that could compromise tool performance.
Heating times are also standardized: for test pieces in a salt bath, cold work steels require 25±1 minutes of hardening time and 60 minutes of tempering time. Thicker tools (over 50mm) need extended heating to ensure uniform temperature penetration.
One of the most valued features of AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is its minimal dimensional distortion after heat treatment, thanks to vanadium grain refinement. This stability is paired with flexible surface finish options to meet specific application needs:
Surface Finishes: Available in turned (+0/+3mm tolerance), milled (+0/+3mm tolerance), ground (+0/+0.05mm tolerance—best for precision tools), polished (+0/+0.05mm tolerance), peeled (+0/+0.1mm tolerance), black forged (+0/+5mm tolerance), and black rolled (+0/+1mm tolerance). Ground and polished finishes are ideal for tools requiring tight fits, such as guide bushings or measuring gauges.
Straightness: Hot-rolled and cold-drawn bars have a maximum straightness of 1mm/1000mm, while black forged products have a maximum of 3mm/1000mm—reducing the need for post-processing to correct warping.
This combination of stability and surface quality ensures tools made from this steel maintain accuracy over long production runs.
Hunan Qilu Steel offers a wide range of sizes for AISI O2 / DIN 1.2842 / ISO 90MnCrV8, with both standard stock and custom-forged options to minimize lead times:
Hot-Rolled Bars: Diameter range Φ10-Φ190mm, length 2000-5800mm (stock diameters include 12mm, 15mm, 18mm, ..., 190mm for immediate delivery).
Hot-Forged Bars: Diameter range Φ200-Φ600mm, length 2000-5800mm (custom diameters available for large-scale orders).
Hot-Rolled Plates/Sheets: Thickness 6-80mm, width 310-810mm, length 2000-5800mm (stock thicknesses: 6mm, 8mm, 10mm, ..., 80mm).
Hot-Forged Blocks: Thickness 260-500mm, width 300-1000mm, length 2000-5800mm.
Stock levels update daily, so customers are advised to contact Hunan Qilu Steel’s sales team for real-time availability.
AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is most widely used in cold work tooling, where its wear resistance and toughness excel. Key applications include:
Stamping Tooling: Ideal for stamping thin sheets (thickness <3mm) of low-carbon steel, copper alloys, and aluminum. Common end products include electronic device casings (e.g., smartphone backplates), hardware fasteners (e.g., screws, washers), and automotive interior components (e.g., dashboard clips). The steel’s high hardness (HRC60 Min) ensures the stamping die retains its sharp edges through thousands of cycles.
Forming Dies: Used for bending, deep drawing, and embossing operations. For example, it is employed in making aluminum cans (deep drawing), stainless steel sinks (bending), and metal nameplates (embossing). Its dimensional stability prevents die warping, ensuring consistent part geometry.
Shearing Tools: Suitable for precision shearing of paper, plastic films, and thin metal sheets (up to 3mm thick). Applications include paper cutting blades for printing presses, plastic sheet cutters for packaging machinery, and metal trim shears for electronics manufacturing. The steel’s wear resistance reduces blade sharpening frequency, lowering maintenance costs.
The balanced hardness and toughness of AISI O2 / DIN 1.2842 / ISO 90MnCrV8 make it an excellent choice for cutting and measuring tools that require both sharpness and durability:
Cutting Tools: Taps (for threading metal), drills (for small-diameter holes in steel), and woodworking chisels. For instance, taps made from this steel can thread low-carbon steel components without fracturing, while woodworking chisels retain their edge longer than those made from lower-grade steels.
Measuring Tools: Wear-resistant gauges such as plug gauges (for checking hole diameters) and snap gauges (for checking shaft diameters). These tools must maintain precise dimensions over time, and the steel’s dimensional stability and corrosion resistance (from chromium) ensure long-term accuracy, even in workshop environments.
Beyond tooling, AISI O2 / DIN 1.2842 / ISO 90MnCrV8 is used in mechanical parts subjected to constant friction:
Guide Bushings: Found in machining centers and injection molding machines, these components guide moving parts (e.g., drill bits, ejector pins) and require high wear resistance. The steel’s hardness prevents premature wear, ensuring smooth operation.
Bearing Cages: Used in small to medium-sized bearings for industrial motors. The steel’s toughness absorbs minor impacts, while its wear resistance extends bearing life.
Textile Machinery Parts: Wear-resistant guide needles for weaving machines. These needles guide yarn through the weaving process and are exposed to constant friction; the steel’s durability reduces needle replacement frequency, minimizing production downtime.
DIN 1.2842 has well-recognized equivalents in major global standards, ensuring compatibility across international supply chains:
U.S. Standard (ASTM A681): AISI O2
European Standard (EN ISO 4957): ISO 90MnCrV8
Chinese Standard (GB/T 1299): 9Mn2V
These equivalents have similar chemical compositions and mechanical properties, so they can be used interchangeably in most cold work applications. For example, AISI O2 can replace DIN 1.2842 in stamping dies without modifying heat treatment or machining processes.
The optimal heat treatment process for AISI O2 steel (to achieve maximum hardness and toughness) is as follows:
Preheating: Heat the steel to 649℃ and hold for 15-20 minutes (adjust based on part thickness) to reduce thermal stress during subsequent heating.
Hardening: Transfer to a salt bath furnace and heat to 780-800℃. Hold for 25±1 minutes (for test pieces; thicker parts require longer holding times, e.g., +5 minutes for every 25mm of thickness).
Quenching: Rapidly cool the steel in mineral oil to room temperature. This step is critical for achieving martensitic structure (the source of high hardness).
Tempering: Reheat the quenched steel to 170-190℃ in a furnace and hold for 60 minutes. Air-cool to room temperature to relieve internal stresses and stabilize dimensions.
Avoid over-tempering (temperatures above 200℃), as this will reduce hardness below the HRC60 Min threshold.
ISO 90MnCrV8 steel balances wear resistance and toughness through its carefully designed composition:
Wear Resistance: Manganese (1.80-2.20%) and chromium (0.20-0.50%) form hard carbide particles in the steel matrix, which resist abrasion during cold working. This makes it suitable for tools that contact hard materials (e.g., steel sheets) repeatedly.
Toughness: Vanadium (0.05-0.20%) refines the grain structure, making the steel less brittle than high-carbon, high-chromium steels (e.g., AISI D2). This toughness allows ISO 90MnCrV8 tools to withstand minor impacts (e.g., accidental contact between the die and a misaligned part) without cracking.
In practical testing, ISO 90MnCrV8 stamping dies last 20-30% longer than dies made from lower-grade cold work steels (e.g., AISI W1), while maintaining better part quality.
Hunan Qilu Steel offers a comprehensive range of sizes for DIN 1.2842, including standard stock and custom options:
Hot-Rolled Bars: Diameter Φ10-Φ190mm, length 2000-5800mm (stock diameters: 12, 15, 18, 20, 22, 25, 28, 30, 32, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190mm).
Hot-Forged Bars: Diameter Φ200-Φ600mm, length 2000-5800mm (custom diameters available for orders over 500kg).
Hot-Rolled Plates: Thickness 6-80mm, width 310-810mm, length 2000-5800mm (stock thicknesses: 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80mm).
Hot-Forged Blocks: Thickness 260-500mm, width 300-1000mm, length 2000-5800mm.
Stock levels change daily, so contact Hunan Qilu Steel via email (enquiry@qilumetal.com) or phone (+86-0731-85185770) for real-time availability.
Yes, all batches of AISI O2 cold work tool steel from Hunan Qilu Steel undergo ultrasonic testing to ensure internal quality. The testing follows either EN10228-3 Class III (European standard) or Sep 1921-84 D/D (German standard), both of which require detecting internal defects (e.g., cracks, inclusions, voids) larger than 1mm in diameter.
Ultrasonic testing is critical for high-stress applications (e.g., stamping dies, cutting tools), as hidden defects can cause sudden tool failure during operation. Customers can request a copy of the ultrasonic test report for each order to verify quality.
1: Steel equivalent
Country | USA | ISO | Germany | China |
Standard | ASTM A681 | ISO 4957 | DIN17350 | GB/T1299 |
Grade | O2 | 90MnCrV8 | 1.2842 | 9Mn2V |
2: Chemical composition
Grade | C | Si | Mn | P | S | Cr | Mo | V |
O2 | 0.85-0.95 | 0.50Max | 1.40-1.80 | 0.030Max | 0.030Max | 0.50Max | 0.30Max | 0.30Max |
90MnCrV8 | 0.85-0.95 | 0.10-0.40 | 1.80-2.20 | 0.030Max | 0.030Max | 0.2-0.5 | / | 0.05-0.20 |
1.2842 | 0.85-0.95 | 0.10-0.40 | 1.90-2.10 | 0.030Max | 0.030Max | 0.2-0.5 | / | 0.05-0.15 |
9Mn2V | 0.85-0.95 | 0.8-1.2 | 1.70-2.00 | 0.030Max | 0.030Max | / | / | 0.10-0.25 |
3: Surface hardness and hardenability.
Heat Treatment | Hardness |
Annealed (+A) | HB229Max |
Cold-drawn condition | HB241Max |
Hardening and Tempering (+HT) | HRC60 Min |
4: Supply size & Tolerance & Stock size
Product type | Size range | Length |
Hot rolled bar | Φ10-Φ190mm | 2000-5800mm |
Hot forged bar | Φ200-Φ600mm | 2000-5800mm |
Hot rolled plate/sheet | T:6-80mm; W:310-810mm | 2000-5800mm |
Hot forged plate | T:70-250mm; W:310-810mm | 2000-5800mm |
Hot Forged block | T: 260-500mm; W: 300-1000mm | 2000-5800mm |
Surface Finish | Turned | Milled | Grinding(Best) | Polished(Best) | Peeled(Best) | Black Forged | Black Rolled |
Tolerance | +0/+3mm | +0/+3mm | +0/+0.05mm | +0/+0.05mm | +0/+0.1mm | +0/+5mm | +0/+1mm |
Straighness | 1mm/1000mm max. | 3mm/1000mm max. | |||||
Qilu steel stock hot rolled bar and hot rolled plate, below our our stock size.
1): Stock diameter for hot rolled bar
12 | 15 | 18 | 20 | 22 | 25 | 28 | 30 | 32 | 35 | 40 | 45 | 50 | 55 | 60 |
65 | 70 | 75 | 80 | 85 | 90 | 95 | 100 | 110 | 120 | 130 | 140 | 150 | 160 | 170 |
180 | 190 | 200 |
2) : Stock thickness for hot rolled plate
6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 25 | 30 |
35 | 40 | 45 | 50 | 55 | 60 | 65 | 70 | 75 | 80 |
Since the stocks change everyday, if you want to know our stock available information, please contact our salesman.
5: Ultrasonic Test
EN10228-3 class III or Sep 1921-84 D/D
6：Steel making & Forging processing
1): Steel making process:
EF+LF+VD
EAF+LF+VD
EF+LF+VD+ESR
EAF+LF+VD+ESR
2): Forging processing:
Put the 1.2842 ingot into the furnace and pre-heat to 650-750℃
Continue heating the ingot to initial temperature: 1050-1100℃
Forge the ingot, forging temperature should be not less than 800-850℃
Cooling in the furnace or in the ash after forging
7: Heat treatment
1): Annealed:
Heat 1.2842 steel to 780-820℃ in the furnace
Soak at this temperature in the furnace
Cooling in the furnace slowly
2): Quenching and tempering:
Preheat Temperature: 649℃
Heat 1.2842 steel to 780-800℃ in the salt bath furnace
Soak at this temperature in the furnace
Quench in oil
Temper steel at 170-190℃ in the furnace
Take out from furnace and cool in the air.
Above curve in figure is just a rough guide to the tempering behaviour of steels. When applying the curves for an estimation of the hardness which can be expected in quenched and tempered tools, it should be taken into account that the optimum heat-treatment conditions for the tools are not necessarily identical with those specified for the test pieces.
The heating time of test pieces in a salt batch shall be as give in below table:
Total heating time of test pieces in a salt bath
Nature of steel | Hardening Time min | Tempering Time min |
Cold or hot work steels | 25 +/- 1 | 60 |
High-speed steels | 3 | Minimum 2 periods of 60 each |
If the test pieces are not heated in a salt batch, the heating time must be extended accordingly, and the times for heating give above are not valid for thicker tools.
