Steel CNC Machining Services
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- ISO 9001:2015 Certified
- Tight Tolerances: Up To ±0.01 mm
- Wide Material Coverage: Carbon Steel, Alloy & Tool Steel
Custom Steel Parts Machining
Steel is an iron–carbon alloy with carbon content typically between 0.02% and 2.14%. Small amounts of elements such as chromium, nickel, molybdenum, or vanadium are often added to improve hardness, corrosion resistance, and strength. It is a versatile metal that is widely used in manufacturing, construction, and industrial applications.
3ERP is a leading provider of steel prototyping services, delivering precision machined steel parts through advanced CNC milling, turning, drilling, and surface finishing. With expertise in carbon steel, stainless steel, alloy steel, and tool steel machining, 3ERP ensures tight tolerances, excellent durability, and reliable performance for industries such as automotive, aerospace, medical devices, and industrial equipment.
Carbon Steels
Low Carbon Steels
Low carbon steels 1215 and 1018 are easy to machine, weld, and form, making them cost-effective for CNC machining. Mild steel is commonly used in fixtures, automotive components, and general-purpose parts.
1215 Steel
- Very machinable due to low carbon (~0.12%) and added sulfur
- Lower strength and hardness than 1018
- Ideal for screws, nuts, bolts, fasteners, and small CNC parts
1018 Steel
- Slightly higher carbon (~0.18%) gives better strength and hardness
- Good weldability and formability
- Suitable for shafts, pins, rods, frames, and moderate-load automotive or machinery parts
Medium Carbon Steel (Steel 1045)
1045 medium carbon steel offers greater strength and toughness compared to 1018, while still maintaining good machinability. It is widely used for shafts, gears, bolts, and other mechanical components that require higher wear resistance and durability.
Other widely used medium carbon steels include 1145F, which is quenched to improve machinability, and 11L41, alloyed with sulfur and lead to enhance cutting performance.
High Carbon Steel (Steel 1095)
High carbon steel like 1095 is very hard and wear-resistant, especially after heat treatment. It is often selected for cutting tools, springs, and high-strength components that demand superior hardness and edge retention.
Alloy Steels
Alloy Steel 4140
4140, also known as 42CrMo4, is a versatile alloy steel valued for its high strength, toughness, and fatigue resistance. It is widely used in aerospace, oil & gas, and automotive industries for critical parts such as shafts, axles, and fasteners.
Alloy Steel 4340
4340 is a low-alloy metal providing excellent toughness, wear resistance, and high tensile strength, even under heavy loads. It is often chosen for demanding applications such as heavy-duty gears, shafts, and structural components that require superior durability.
Tool Steels
O1, A2, D2
O1 (oil-hardening), A2 (air-hardening), and D2 (high-carbon, high-chromium) tool steels are very hard and highly wear-resistant after heat treatment. They are commonly used for dies, molds, cutting tools, and other applications requiring long-term dimensional stability and durability.
H13
H13 tool steel offers excellent heat resistance and toughness, making it ideal for hot work tooling, die casting molds, and components exposed to high thermal stress.
Surface Finishes for Steel Parts
Steel is prone to oxidation due to its iron content, so surface treatments are often applied for long-term durability. 3ERP provides full CNC machining services with optional secondary processes—such as surface finishing, coating, spraying, and heat treatment—to improve both the appearance and performance of steel parts.
Benefits and Limitations of Steel Machining
Benefits
High Strength & Durability
Steel parts retain excellent mechanical strength and wear resistance, making them ideal for structural and high-load components.
Good Machinability
Low and medium carbon steels are easy to cut, drill, and mill, reducing production time and tool wear.
Versatility
Steel can be used in a wide range of applications, from automotive parts to industrial machinery and tooling.
Cost-Effective
Compared to stainless steel or specialty alloys, carbon and alloy steels provide excellent performance at a lower material cost.
Heat Treatment Compatibility
Steel can be further hardened or tempered after machining to improve wear resistance and toughness.
Limitations
Tool Wear
Machining harder steels, such as high-carbon or tool steels, can cause faster wear on cutting tools.
Energy & Equipment Requirements
Steel requires more robust machines and higher cutting forces than softer metals like aluminum.
Processing Speed Limits
Hard or alloyed steels often must be machined at slower speeds to prevent overheating, work hardening, or surface damage.
Post-Machining Finishing
Certain steels, especially high-carbon or alloy steels, may require heat treatment or surface finishing for optimal performance.
Applications of Steel Parts
Automotive
Precision steel parts such as shafts, gears, and fasteners are essential for engines, suspensions, and drivetrains, providing strength and wear resistance.
Aerospace
High-strength steel components, including landing gear parts, engine shafts, and structural brackets, ensure safety and reliability in critical aerospace systems.
Industrial Machinery
Steel parts like drive shafts, gears, bearings, and machine frames deliver durability and load-bearing performance for heavy-duty equipment.
Oil & Gas
CNC machined steel components such as valves, flanges, pumps, and couplings withstand extreme pressures and harsh environments.
Medical Devices
Precision steel parts are essential in medical instruments and devices, where accuracy and reliability are paramount.
Tooling & Manufacturing
Steel tooling, dies, molds, jigs, and fixtures provide long-lasting performance for stamping, molding, and machining operations.
General Engineering & Custom Components
Custom CNC steel parts, including shafts, rods, brackets, and fasteners, meet specialized requirements for strength, precision, and durability.
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