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E: enquiry@qilumetal.com
E: enquiry@qilumetal.com
No. 18 Xiangfu Middle Road,Yuhua District, Changsha City
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1040
Qilu
C40 / 1.0511 is a widely used medium-carbon quality steel that complies with the European standards EN 10083-2 and EN 10250-2. With a carbon content ranging from 0.37% to 0.44%, this steel delivers an excellent balance of strength, toughness, and wear resistance after undergoing normalizing or quenching and tempering heat treatment. Its consistent microstructure and reliable mechanical properties make it a top choice for components that bear moderate stresses. It is extensively used in machinery manufacturing, the automotive industry, and general engineering fields, thanks to its good machinability and heat treatability, which ensure long-term reliability and durability across diverse industrial applications.
Different countries and regions have established their own standards for medium-carbon steel. The following table clearly presents the equivalent grades of C40 steel in major international standards, helping buyers and engineers accurately select materials for cross-border projects.
Country | China | Japan | Europe | USA | British |
Standard | GB/T 699 | JIS G4051 | EN10250-2 | ASTM A29 | BS 970 |
Grade | 40# | S40C | C40/1.0511 | 1040 | 080M40 |
The chemical composition is the core factor that determines the performance of steel. The table below details the element content ranges of C40 and its equivalent grades, which is crucial for predicting the steel's heat treatment response and mechanical behavior.
Grade | C | Si | Mn | P | S | Cr |
| 40# | 0.37-0.44 | 0.17-0.37 | 0.50-0.80 | 0.035Max | 0.035Max | 0.25 |
| S40C | 0.37-0.43 | 0.15-0.35 | 0.60-0.90 | 0.030Max | 0.035Max | 0.20 |
| C40/1.0511 | 0.37-0.44 | 0.40Max | 0.50-0.80 | 0.045Max | 0.045Max | 0.40 |
| 1040 | 0.37-0.44 | 0.10Max | 0.60-0.90 | 0.040Max | 0.050Max | / |
| 080M40 | 0.36-0.44 | 0.10-0.40 | 0.60-1.00 | 0.050Max | 0.050Max | / |
The mechanical properties of C40 steel vary significantly under different heat treatment processes and product forms. The following data is based on the standards EN 10083-2 and EN 10250-2, providing a reliable basis for structural design and performance testing.
Mechanical properties for C40 quenching and tempering carbon steel according to EN10083-2.
Size range | Tensile strength | Yield strength | Alongation | Area of reduction | Impact value At RT/J |
d≤16 t≤8 | 650-800Mpa | 460Mpa Min | 16% Min | 35% Min | / |
16＜d≤40 8＜t≤20 | 630-780Mpa | 400Mpa Min | 18% Min | 40%Min | / |
| 40＜d≤100 20＜t≤60 | 600-750Mpa | 350Mpa Min | 19% Min | 45%Min | / |
Mechanical properties for C40 normalizing carbon steel according to EN10083-2 and ISO683-1.
Size range | Tensile strength | Yield strength | Alongation | Area of reduction | Impact value At RT/J |
d≤16 t≤16 | 580Mpa | 320Mpa Min | 16% Min | / | / |
16＜d≤100 16＜t≤100 | 550Mpa | 290Mpa Min | 17% Min | / | / |
100＜d≤250 100＜t≤250 | 530Mpa | 260Mpa Min | 17% Min | / | / |
Mechanical properties for C40 open die forgings steel in the normalized and normalized and tempered conditions according to EN10250-2.
Size range | Tensile strength | Yield strength | Alongation | Impact value at RT/J | ||
L | Tr | L | Tr | |||
| d≤100 | 550Mpa Min | 290Mpa Min | 17% Min | / | / | / |
| 100＜d≤250 | 530Mpa Min | 260Mpa Min | 17% Min | / | / | / |
Remark: L= Longitudinal Tr = Transverse
Quenching and Tempering Steel: Samples are taken at a distance of 12.5mm below the heat-treated surface in accordance with EN10083-1, or as specified in the buyer-seller contract.
Open Die Forgings: Samples are taken at 4/T below the heat-treated surface, with a minimum of 20mm and a maximum of 80mm, and at t/2 from the end. The parameter t refers to the equivalent thickness of the ruling section of the forging during heat treatment. This sampling method follows EN10250-1, or can be adjusted according to the contract.
The hardness of C40 steel can be adjusted through various heat treatment processes to meet the requirements of different application scenarios.
Heat Treatment | Hardness |
Treated to improve shearability (+S) | HB160Max |
Soft annealed (+A) | HB145Max |
Quenched and tempred (+QT) | HRC28-32(Common Range) |
When ordering C40 steel with normal (+H) or restricted (+HL, +HH) hardenability requirements, the hardness values at different distances from the quenched end are as follows:
Distance in mm from quenched end | |||||||||||||||||
Distance | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 13 | 15 | 20 | 25 | 30 | |
Hardness In HRC + H | max | 60 | 60 | 59 | 57 | 53 | 47 | 39 | 34 | 31 | 30 | 29 | 28 | 27 | / | / | / |
min | 51 | 46 | 35 | 27 | 25 | 24 | 23 | 22 | 21 | 20 | / | / | / | / | / | / | |
Hardness In HRC + HH | +HH4 | / | / | / | 38-57 | / | / | / | / | / | / | / | / | / | / | / | / |
+HH14 | 54-60 | / | / | 38-57 | / | / | / | / | / | / | / | / | / | / | / | / | |
Hardness In HRC + HL | +HL4 | / | / | / | 27-46 | / | / | / | / | / | / | / | / | / | / | / | / |
+HL14 | 51-57 | / | / | 27-46 | / | / | / | / | / | / | / | / | / | / | / | / | |
Scatter bands for the Rockwell - C hardness in the end quench hardenability test.
We provide C40 steel in various product forms to meet the diverse needs of customers in different industries.
Product type | Size range | Length |
Cold drawn bar | Φ3-Φ80mm | 6000-9000mm |
Hot rolled bar | Φ16-Φ310mm | 6000-9000mm |
Hot forged bar | Φ100-Φ1200mm | 3000-5800mm |
Hot rolled plate/sheet | T:3-200mm; W:1500-2500mm | 2000-5800mm |
Hot Forged block | T: 80-800mm; W: 100-2500mm | 2000-5800mm |
The surface finish of C40 steel affects its corrosion resistance, machining accuracy and appearance. The following are the tolerance and straightness parameters corresponding to different surface treatments.
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 maintains a large monthly stock of hot rolled and forged bars of C40 steel, with the following common stock diameters available for quick delivery:
Hot Rolled Bar Stock Diameters (mm): 16, 18, 20, 22, 24, 25, 26, 27, 28, 30, 31, 32, 33, 35, 36, 38, 39, 40, 42, 45, 46, 48, 50, 52, 55, 56, 58, 60, 62, 63, 65, 68, 70, 72, 75, 78, 80, 82, 83, 85, 87, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310
Hot Forged Bar Stock Diameters (mm): 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 500, 510, 520, 530, 540, 550
Note: Stock availability changes daily. For the latest stock information, please contact our sales team.
The forging process is key to improving the internal structure of C40 steel and eliminating casting defects. The standard forging steps are as follows:
Heat the C40 steel ingot in a furnace to a temperature range of 1150-1200℃.
Perform the forging operation when the ingot temperature is not lower than 800-850℃ to ensure good plasticity of the steel.
Cool the forged steel in air or in the furnace, depending on the required performance and product size.
Reasonable heat treatment can optimize the mechanical properties of C40 steel. The specific parameters of common heat treatment processes are as follows:
Soft Annealing (+A): Heat the steel to 840-860℃ in a furnace, hold it at this temperature for a sufficient period, and then cool it slowly in the furnace. This process reduces the hardness of the steel and improves its machinability.
Normalizing: Heat the steel to 850-910℃, keep it warm, and then cool it in air. Normalizing can refine the grain of the steel and improve its overall mechanical properties.
Quenching and Tempering (+QT): First, heat the steel to 830-870℃, hold it for heat preservation, and then quench it in water or oil. Then, temper the steel at 550-660℃ and cool it in air. The lower end of the heating temperature range is suitable for water quenching, and the upper end is suitable for oil quenching. This process achieves the optimal balance of strength and toughness of the steel.
C40 steel has very limited weldability due to its medium carbon content of approximately 0.40%. Weldability decreases significantly as the carbon content increases. Without strict preheating and post-weld heat treatment, C40 steel is highly prone to cracking during the welding process.
During welding, the high carbon content will promote the formation of hard and brittle martensitic structures in the heat-affected zone (HAZ). The presence of hydrogen in the welding process will further increase the risk of cold cracking.
Preheat the base metal to 200-300℃ before welding to reduce the cooling rate of the weld zone.
Use low-hydrogen welding electrodes or welding wires to minimize the hydrogen content in the weld.
Perform stress relief annealing after welding, heating the welded component to 550-600℃ and holding it for a certain period before cooling it slowly.
As a classic medium-carbon steel, C40 steel is widely used in various industries due to its excellent comprehensive performance. Its main application areas and specific uses are as follows:
Shaft Components: Drive shafts, spindles, mandrels, lead screws, etc.
Gears and Gear Rings: Low-speed and low-load gears for machine tools, automotive transmissions, and agricultural machinery.
Connectors and Fasteners: High-strength bolts, double-headed studs, positioning pins, etc.
Connecting Rods and Cranks: Used in internal combustion engines, compressors, and other equipment to transmit motion and power.
Mold Components: Non-core parts of injection molds, mold bases, spacer plates, guide pillars, etc.
Tool Bodies: Hand tools such as hammers, wrenches, pliers, and screwdrivers.
Blades and Cutting Tools: Woodworking tools, agricultural machinery blades, and cutting tools with moderate hardness requirements.
Key Components: Crankshafts, camshafts, steering knuckles, half-shafts, brake discs, etc.
Hydraulic and Pneumatic Components: Hydraulic cylinder piston rods, pneumatic cylinder rods, valve cores, etc.
Locomotive Manufacturing: Locomotive axles, connecting rods, and bogie components.
Agricultural Machinery: Plowshares, harrow teeth, gearboxes, and other parts subject to wear and impact.
To help customers better understand and use C40 steel, we have sorted out the most frequently asked questions during the purchasing and application process:
A1: The core difference lies in the carbon content. C40 steel has a carbon content of 0.37-0.44%, which is much higher than that of Q235 (0.14-0.22%). This makes C40 steel have higher strength and hardness after heat treatment, but its weldability and plasticity are lower than Q235. C40 steel is suitable for load-bearing components, while Q235 is more suitable for structural parts and welding components.
A2: Yes. After precision machining processes such as grinding and polishing, combined with quenching and tempering heat treatment, C40 steel can achieve high dimensional accuracy and surface finish, meeting the requirements of most medium-precision mechanical components. For ultra-high-precision components, it is recommended to use alloy steel or tool steel.
A3: The long-term service temperature of C40 steel should not exceed 400℃. When the temperature is higher than this value, the strength and hardness of the steel will decrease significantly. For high-temperature working conditions, it is recommended to use heat-resistant alloy steel.
A4: The carbon content of 45 steel (0.42-0.50%) is slightly higher than that of C40 steel. Therefore, 45 steel has higher hardness after quenching, but its toughness is slightly lower. C40 steel has a better balance of strength and toughness and is more suitable for components that require both wear resistance and impact resistance, while 45 steel is suitable for components that focus on hardness and wear resistance.
A5: C40 steel is a carbon steel without alloying elements such as chromium and nickel, so its natural corrosion resistance is poor. For components used in humid or corrosive environments, surface treatment measures such as galvanizing, painting, or nitriding are required to improve corrosion resistance.
A6: Common delivery conditions include:
As-rolled or As-forged (Black Condition): The most cost-effective option, with mill scale on the surface.
Normalized (N): Improves microstructural uniformity, preparing the steel for further machining or heat treatment.
Quenched and Tempered (QT): Delivered in a heat-treated state with high strength and good toughness, ready for final machining or use.
Rough Machined: Turned, ground, or peeled to remove surface decarburization and reduce customer processing time.
A7: Yes. Qilu Steel not only supplies standard material forms but also offers custom forging and rough machining services. We can produce near-net-shape forgings based on your provided drawings or samples, and perform necessary heat treatments and preliminary machining to help you save costs and shorten lead times.
C40 / 1.0511 is a widely used medium-carbon quality steel that complies with the European standards EN 10083-2 and EN 10250-2. With a carbon content ranging from 0.37% to 0.44%, this steel delivers an excellent balance of strength, toughness, and wear resistance after undergoing normalizing or quenching and tempering heat treatment. Its consistent microstructure and reliable mechanical properties make it a top choice for components that bear moderate stresses. It is extensively used in machinery manufacturing, the automotive industry, and general engineering fields, thanks to its good machinability and heat treatability, which ensure long-term reliability and durability across diverse industrial applications.
Different countries and regions have established their own standards for medium-carbon steel. The following table clearly presents the equivalent grades of C40 steel in major international standards, helping buyers and engineers accurately select materials for cross-border projects.
Country | China | Japan | Europe | USA | British |
Standard | GB/T 699 | JIS G4051 | EN10250-2 | ASTM A29 | BS 970 |
Grade | 40# | S40C | C40/1.0511 | 1040 | 080M40 |
The chemical composition is the core factor that determines the performance of steel. The table below details the element content ranges of C40 and its equivalent grades, which is crucial for predicting the steel's heat treatment response and mechanical behavior.
Grade | C | Si | Mn | P | S | Cr |
| 40# | 0.37-0.44 | 0.17-0.37 | 0.50-0.80 | 0.035Max | 0.035Max | 0.25 |
| S40C | 0.37-0.43 | 0.15-0.35 | 0.60-0.90 | 0.030Max | 0.035Max | 0.20 |
| C40/1.0511 | 0.37-0.44 | 0.40Max | 0.50-0.80 | 0.045Max | 0.045Max | 0.40 |
| 1040 | 0.37-0.44 | 0.10Max | 0.60-0.90 | 0.040Max | 0.050Max | / |
| 080M40 | 0.36-0.44 | 0.10-0.40 | 0.60-1.00 | 0.050Max | 0.050Max | / |
The mechanical properties of C40 steel vary significantly under different heat treatment processes and product forms. The following data is based on the standards EN 10083-2 and EN 10250-2, providing a reliable basis for structural design and performance testing.
Mechanical properties for C40 quenching and tempering carbon steel according to EN10083-2.
Size range | Tensile strength | Yield strength | Alongation | Area of reduction | Impact value At RT/J |
d≤16 t≤8 | 650-800Mpa | 460Mpa Min | 16% Min | 35% Min | / |
16＜d≤40 8＜t≤20 | 630-780Mpa | 400Mpa Min | 18% Min | 40%Min | / |
| 40＜d≤100 20＜t≤60 | 600-750Mpa | 350Mpa Min | 19% Min | 45%Min | / |
Mechanical properties for C40 normalizing carbon steel according to EN10083-2 and ISO683-1.
Size range | Tensile strength | Yield strength | Alongation | Area of reduction | Impact value At RT/J |
d≤16 t≤16 | 580Mpa | 320Mpa Min | 16% Min | / | / |
16＜d≤100 16＜t≤100 | 550Mpa | 290Mpa Min | 17% Min | / | / |
100＜d≤250 100＜t≤250 | 530Mpa | 260Mpa Min | 17% Min | / | / |
Mechanical properties for C40 open die forgings steel in the normalized and normalized and tempered conditions according to EN10250-2.
Size range | Tensile strength | Yield strength | Alongation | Impact value at RT/J | ||
L | Tr | L | Tr | |||
| d≤100 | 550Mpa Min | 290Mpa Min | 17% Min | / | / | / |
| 100＜d≤250 | 530Mpa Min | 260Mpa Min | 17% Min | / | / | / |
Remark: L= Longitudinal Tr = Transverse
Quenching and Tempering Steel: Samples are taken at a distance of 12.5mm below the heat-treated surface in accordance with EN10083-1, or as specified in the buyer-seller contract.
Open Die Forgings: Samples are taken at 4/T below the heat-treated surface, with a minimum of 20mm and a maximum of 80mm, and at t/2 from the end. The parameter t refers to the equivalent thickness of the ruling section of the forging during heat treatment. This sampling method follows EN10250-1, or can be adjusted according to the contract.
The hardness of C40 steel can be adjusted through various heat treatment processes to meet the requirements of different application scenarios.
Heat Treatment | Hardness |
Treated to improve shearability (+S) | HB160Max |
Soft annealed (+A) | HB145Max |
Quenched and tempred (+QT) | HRC28-32(Common Range) |
When ordering C40 steel with normal (+H) or restricted (+HL, +HH) hardenability requirements, the hardness values at different distances from the quenched end are as follows:
Distance in mm from quenched end | |||||||||||||||||
Distance | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 13 | 15 | 20 | 25 | 30 | |
Hardness In HRC + H | max | 60 | 60 | 59 | 57 | 53 | 47 | 39 | 34 | 31 | 30 | 29 | 28 | 27 | / | / | / |
min | 51 | 46 | 35 | 27 | 25 | 24 | 23 | 22 | 21 | 20 | / | / | / | / | / | / | |
Hardness In HRC + HH | +HH4 | / | / | / | 38-57 | / | / | / | / | / | / | / | / | / | / | / | / |
+HH14 | 54-60 | / | / | 38-57 | / | / | / | / | / | / | / | / | / | / | / | / | |
Hardness In HRC + HL | +HL4 | / | / | / | 27-46 | / | / | / | / | / | / | / | / | / | / | / | / |
+HL14 | 51-57 | / | / | 27-46 | / | / | / | / | / | / | / | / | / | / | / | / | |
Scatter bands for the Rockwell - C hardness in the end quench hardenability test.
We provide C40 steel in various product forms to meet the diverse needs of customers in different industries.
Product type | Size range | Length |
Cold drawn bar | Φ3-Φ80mm | 6000-9000mm |
Hot rolled bar | Φ16-Φ310mm | 6000-9000mm |
Hot forged bar | Φ100-Φ1200mm | 3000-5800mm |
Hot rolled plate/sheet | T:3-200mm; W:1500-2500mm | 2000-5800mm |
Hot Forged block | T: 80-800mm; W: 100-2500mm | 2000-5800mm |
The surface finish of C40 steel affects its corrosion resistance, machining accuracy and appearance. The following are the tolerance and straightness parameters corresponding to different surface treatments.
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 maintains a large monthly stock of hot rolled and forged bars of C40 steel, with the following common stock diameters available for quick delivery:
Hot Rolled Bar Stock Diameters (mm): 16, 18, 20, 22, 24, 25, 26, 27, 28, 30, 31, 32, 33, 35, 36, 38, 39, 40, 42, 45, 46, 48, 50, 52, 55, 56, 58, 60, 62, 63, 65, 68, 70, 72, 75, 78, 80, 82, 83, 85, 87, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, 150, 155, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 310
Hot Forged Bar Stock Diameters (mm): 310, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 500, 510, 520, 530, 540, 550
Note: Stock availability changes daily. For the latest stock information, please contact our sales team.
The forging process is key to improving the internal structure of C40 steel and eliminating casting defects. The standard forging steps are as follows:
Heat the C40 steel ingot in a furnace to a temperature range of 1150-1200℃.
Perform the forging operation when the ingot temperature is not lower than 800-850℃ to ensure good plasticity of the steel.
Cool the forged steel in air or in the furnace, depending on the required performance and product size.
Reasonable heat treatment can optimize the mechanical properties of C40 steel. The specific parameters of common heat treatment processes are as follows:
Soft Annealing (+A): Heat the steel to 840-860℃ in a furnace, hold it at this temperature for a sufficient period, and then cool it slowly in the furnace. This process reduces the hardness of the steel and improves its machinability.
Normalizing: Heat the steel to 850-910℃, keep it warm, and then cool it in air. Normalizing can refine the grain of the steel and improve its overall mechanical properties.
Quenching and Tempering (+QT): First, heat the steel to 830-870℃, hold it for heat preservation, and then quench it in water or oil. Then, temper the steel at 550-660℃ and cool it in air. The lower end of the heating temperature range is suitable for water quenching, and the upper end is suitable for oil quenching. This process achieves the optimal balance of strength and toughness of the steel.
C40 steel has very limited weldability due to its medium carbon content of approximately 0.40%. Weldability decreases significantly as the carbon content increases. Without strict preheating and post-weld heat treatment, C40 steel is highly prone to cracking during the welding process.
During welding, the high carbon content will promote the formation of hard and brittle martensitic structures in the heat-affected zone (HAZ). The presence of hydrogen in the welding process will further increase the risk of cold cracking.
Preheat the base metal to 200-300℃ before welding to reduce the cooling rate of the weld zone.
Use low-hydrogen welding electrodes or welding wires to minimize the hydrogen content in the weld.
Perform stress relief annealing after welding, heating the welded component to 550-600℃ and holding it for a certain period before cooling it slowly.
As a classic medium-carbon steel, C40 steel is widely used in various industries due to its excellent comprehensive performance. Its main application areas and specific uses are as follows:
Shaft Components: Drive shafts, spindles, mandrels, lead screws, etc.
Gears and Gear Rings: Low-speed and low-load gears for machine tools, automotive transmissions, and agricultural machinery.
Connectors and Fasteners: High-strength bolts, double-headed studs, positioning pins, etc.
Connecting Rods and Cranks: Used in internal combustion engines, compressors, and other equipment to transmit motion and power.
Mold Components: Non-core parts of injection molds, mold bases, spacer plates, guide pillars, etc.
Tool Bodies: Hand tools such as hammers, wrenches, pliers, and screwdrivers.
Blades and Cutting Tools: Woodworking tools, agricultural machinery blades, and cutting tools with moderate hardness requirements.
Key Components: Crankshafts, camshafts, steering knuckles, half-shafts, brake discs, etc.
Hydraulic and Pneumatic Components: Hydraulic cylinder piston rods, pneumatic cylinder rods, valve cores, etc.
Locomotive Manufacturing: Locomotive axles, connecting rods, and bogie components.
Agricultural Machinery: Plowshares, harrow teeth, gearboxes, and other parts subject to wear and impact.
To help customers better understand and use C40 steel, we have sorted out the most frequently asked questions during the purchasing and application process:
A1: The core difference lies in the carbon content. C40 steel has a carbon content of 0.37-0.44%, which is much higher than that of Q235 (0.14-0.22%). This makes C40 steel have higher strength and hardness after heat treatment, but its weldability and plasticity are lower than Q235. C40 steel is suitable for load-bearing components, while Q235 is more suitable for structural parts and welding components.
A2: Yes. After precision machining processes such as grinding and polishing, combined with quenching and tempering heat treatment, C40 steel can achieve high dimensional accuracy and surface finish, meeting the requirements of most medium-precision mechanical components. For ultra-high-precision components, it is recommended to use alloy steel or tool steel.
A3: The long-term service temperature of C40 steel should not exceed 400℃. When the temperature is higher than this value, the strength and hardness of the steel will decrease significantly. For high-temperature working conditions, it is recommended to use heat-resistant alloy steel.
A4: The carbon content of 45 steel (0.42-0.50%) is slightly higher than that of C40 steel. Therefore, 45 steel has higher hardness after quenching, but its toughness is slightly lower. C40 steel has a better balance of strength and toughness and is more suitable for components that require both wear resistance and impact resistance, while 45 steel is suitable for components that focus on hardness and wear resistance.
A5: C40 steel is a carbon steel without alloying elements such as chromium and nickel, so its natural corrosion resistance is poor. For components used in humid or corrosive environments, surface treatment measures such as galvanizing, painting, or nitriding are required to improve corrosion resistance.
A6: Common delivery conditions include:
As-rolled or As-forged (Black Condition): The most cost-effective option, with mill scale on the surface.
Normalized (N): Improves microstructural uniformity, preparing the steel for further machining or heat treatment.
Quenched and Tempered (QT): Delivered in a heat-treated state with high strength and good toughness, ready for final machining or use.
Rough Machined: Turned, ground, or peeled to remove surface decarburization and reduce customer processing time.
A7: Yes. Qilu Steel not only supplies standard material forms but also offers custom forging and rough machining services. We can produce near-net-shape forgings based on your provided drawings or samples, and perform necessary heat treatments and preliminary machining to help you save costs and shorten lead times.
