Custom Stainless Steel Parts Manufacturer

440C stainless steel

ATA – Leading Custom Stainless Steel Fabricator Specialized in 440C Stainless Steel Precision Machining, Heat Treatment & High-Wear Component Manufacturing

Custom Manufacturer

ATA 440C Stainless Steel: Specialized High-Hardness Fabrication & Precision CNC Machining Solutions

ATA delivers expert, application-specific processing for 440C stainless steel – the hardest standard martensitic stainless steel grade – covering precision cutting, complex forming, controlled welding, specialized heat treatment, and tight-tolerance finishing, with consistent quality for prototype development and mass industrial production of high-wear, high-precision components.
Product Form
Standard Processing Size Range
Controlled Tolerance (ISO 2768 & ANSI B4.1)
Stainless Steel Plate/Sheet
0.8mm – 40mm thickness; Max 1500mm x 4000mm dimensions
±0.05mm (precision thin sheets); ±0.12mm (thick plates)
Round Bar/Profile
8mm – 180mm diameter; Max 5000mm length
±0.02mm (precision machined parts); ±0.08mm (standard profiles)
Custom Fabricated Assemblies
Custom-sized per client technical drawings
±0.06mm (critical functional dimensions); ±0.15mm (non-critical dimensions)

Why Your Project Requires 440C Stainless Steel

440C stainless steel is a premium high-carbon martensitic stainless steel that stands as the hardest and most wear-resistant standard stainless steel grade on the market, offering exceptional hardness, superior wear retention, and moderate corrosion resistance after proper quenching and tempering. Unlike lower-grade martensitic stainless steels, 440C maintains sharp edge retention and exceptional durability under high friction, heavy load, and mild corrosive conditions, making it irreplaceable for high-wear, high-precision applications. It is widely used in demanding sectors including Aerospace & Defense, Industrial Machinery Manufacturing, Pharmaceutical & Biotechnology, precision instruments, and valve systems, where standard stainless steels cannot meet wear and hardness requirements. 440C stainless steel also offers good dimensional stability after heat treatment, making it ideal for long-life, high-performance industrial components that require minimal maintenance and maximum durability.
metal
Material Grade
Core Performance Traits
Best Suited Applications
440C Stainless Steel
Ultra-high-carbon martensitic grade, max hardness ≥58 HRC, exceptional wear resistance, moderate corrosion resistance, high dimensional stability
Precision bearings, cutting tools, high-wear valves, aerospace components, precision instrument parts
420 Stainless Steel
Medium-carbon martensitic grade, hardness ≥40 HRC, good wear resistance, better ductility than 440C
Pump shafts, valve cores, general industrial wear parts, surgical tools
410 Stainless Steel
Low-carbon martensitic grade, low hardness, excellent ductility, basic corrosion resistance, cost-effective
General hardware, structural brackets, low-stress fasteners, non-critical industrial parts

ATA Stainless steel fabrication

ATA 440C Stainless Steel Products

Miniature precision stainless steel nuts

Stainless Steel Precision Machined

Custom high-precision 440C stainless steel components including bearing sleeves, precision shafts, and instrument inserts, processed via advanced CNC machining to achieve tight tolerances and ultra-smooth finishes, leveraging 440C’s extreme hardness for long-term wear resistance in high-precision equipment.

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Ball-Type Stainless Steel Valve

Stainless Steel Valve

Premium 440C stainless steel valve discs, stems, and sealing components designed for high-pressure, high-wear fluid systems; the material’s superior wear and corrosion resistance ensure reliable sealing and extended service life in harsh industrial fluid control scenarios.

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Stainless steel fasteners

Stainless Steel Fasteners

High-strength 440C stainless steel fasteners for heavy-duty, high-wear applications, including custom bolts and precision screws; these fasteners deliver exceptional tensile strength and wear resistance, outperforming standard stainless fasteners in demanding industrial and aerospace assemblies.

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Anti-slip Stainless steel brackets

Stainless Steel Brackets

Heavy-duty precision brackets fabricated from 440C stainless steel, ideal for high-load, high-friction industrial machinery and aerospace fixtures; the material’s hardness and structural stability prevent deformation under heavy stress and prolonged use.

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Waterproof Stainless Steel Enclosure

Stainless Steel Enclosure

Specialized 440C stainless steel enclosures for high-protection industrial and precision instrument use, offering exceptional impact resistance and mild corrosion protection, perfect for housing sensitive equipment in harsh industrial environments.

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Asian workers on the production floor of ATA factory

Drawered Stainless Steel Workbench

  • End-to-End Customization: From concept to production, we handle it all

  • Precision Engineering: Advanced machinery and skilled craftsmanship

  • Fast Turnaround: Quick quotes, rapid prototyping, on-time delivery

  • Export-Ready Packaging: Safe and secure for international shipping

ATA Stainless steel fabrication Center

ATA Stainless Steel fabrication: One-Stop Precision Solutions for Your Stainless Steel Needs.

440C Stainless Steel Technical Specs

Chemical Composition

Element
Typical Content Range (wt%)
Carbon (C)
0.95 – 1.20
Chromium (Cr)
16.00 – 18.00
Molybdenum (Mo)
0.40 – 0.60
Manganese (Mn)
≤1.00
Silicon (Si)
≤1.00
Phosphorus (P)
≤0.040
Sulfur (S)
≤0.030
Nickel (Ni)
≤0.75

Mechanical Properties

Mechanical Property
Typical Value
Tensile Strength (Quenched & Tempered)
≥1900 MPa (275 ksi)
Yield Strength (0.2% Offset)
≥1650 MPa (240 ksi)
Elongation (A5)
≥2%
Hardness (Annealed Condition)
≤280 HBW
Hardness (Quenched & Tempered)
≥58 HRC
Density
7.78 g/cm³
Magnetic Property
Ferromagnetic

Fabrication Capabilities

ATA 440C Stainless Steel Fabrication Capabilities

  • Maximum Processing Diameter & Length: ATA processes Stainless Steel Round Bar in 440C grade up to 180mm in diameter and max 5000mm in length; custom oversized precision parts are produced via segmented machining and precision assembly, with strict dimensional control to meet high-precision project requirements for 440C stainless steel.
  • Maximum Plate Thickness Cutting: We handle 440C stainless steel plates from 0.8mm thin sheets to 40mm thick plates, using high-precision Stainless Steel Laser Cutting and Stainless Steel Waterjet Cutting to ensure burr-free edges, no thermal deformation, and consistent cutting accuracy for this high-hardness material.
  • Core Processing Methods: Full-service fabrication including Stainless Steel Sheet Fabrication, precision bending, stamping, andStainless Steel CNC Machining Services; we specialize in complex 440C stainless steel parts, optimizing processing parameters for its high hardness and brittle nature post-heat treatment.
  • Specialized Welding Capabilities: Controlled welding for 440C stainless steel using TIG Welding Stainless Steel with strict pre-heating and post-weld slow cooling protocols, as 440C is highly prone to cracking; our certified welders specialize in martensitic stainless steel welding to ensure defect-free joints.
  • Professional Heat Treatment: Specialized quenching, tempering, and annealing services for 440C stainless steel, critical to unlocking its ultra-high hardness and wear resistance; we customize heat treatment cycles to balance hardness and ductility based on specific application needs.

440C Stainless Steel Fabrication & Manufacturing Key Considerations

To improve processing efficiency, reduce costs and ensure product quality, ATA provides the following professional suggestions for the drawing stage:
  • Recommended Corner Radius, Dimensional Tolerance & Weld Preparation: For 440C stainless steel formed parts, set a minimum inside corner radius of 2x material thickness to avoid cracking during Stainless Steel Bending; reserve 3-4mm weld gaps and avoid sharp internal corners to reduce stress concentration, a critical rule for this high-carbon brittle material.
  • Surface Roughness (Ra) Recommendations: Standard 440C stainless steel industrial parts recommend Ra 1.6μm – 3.2μm; precision high-wear components require Ra 0.8μm – 1.6μm. Post-machining Passivation of Stainless Steel and Stainless Steel Grinding are recommended to enhance surface finish and corrosion resistance.
  • Recommended Tolerance Grades (ISO/ANSI): Use ISO 2768-f (fine tolerance) or ANSI B4.1 close tolerance for critical 440C stainless steel dimensions; ISO 2768-m (medium tolerance) for non-critical dimensions. Avoid overly tight tolerances to balance processing difficulty and production cost for this high-hardness material.
  • Other Suggestions: Avoid sharp corners in the design of 304 stainless steel components; for components used in outdoor environments, reserve 3-5mm drainage gaps to prevent water accumulation and corrosion.

ATA 440C Stainless Steel Fabrication Capabilities FAQs

Q1: Does ATA provide specialized heat treatment for 440C stainless steel to reach 58+ HRC hardness?
A1: Yes, ATA offers professional quenching and tempering services exclusively for 440C stainless steel, with precise temperature control to achieve a minimum hardness of 58 HRC, unlocking its maximum wear resistance while minimizing brittleness for optimal part performance.
A2: We implement strict pre-heating before welding, slow cooling post-welding, and optimized bending radii for forming; our team has extensive experience processing high-carbon martensitic 440C stainless steel, with tailored protocols to eliminate cracking and material failure.
A3: Absolutely, ATA supports full order flexibility for 440C stainless steel fabrication, from 1-30 unit precision prototypes to large-scale mass production. Our flexible production lines and specialized tooling ensure consistent quality, tight tolerances, and competitive lead times for all order volumes.
A4: Yes, 440C’s ultra-high hardness requires specialized carbide cutting tools and optimized CNC machining parameters; we conduct annealing for rough machining when needed, and finish machining post-heat treatment to ensure dimensional accuracy and extend tool life.
A5: Yes, we supply full ASTM-compliant material certification (chemical composition and mechanical property reports) for all 440C stainless steel raw materials, plus post-fabrication hardness and dimensional inspection reports, guaranteeing material authenticity and quality for critical industrial applications.

Premium Knife-Grade Custom 440C Stainless Steel Products

ATA is your trusted professional manufacturer specializing in high-precision stainless steel fabrication, providing custom one-stop solutions for your projects.

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