You’ve come to the right place if you’re an engineer or purchasing manager looking for detailed specifications for C3-80 grade material. Huaxiao Metal supplies stainless steel for a variety of precision, high-performance applications. C3-80 is a high-strength, corrosion-resistant martensitic stainless steel primarily defined by the ISO 3506-1:2020 fastener standard.
The “-80” designation is crucial—it signifies a tensile strength of at least 800 MPa, making this material a top choice for applications requiring the highest performance and reliability.
As a leading international supplier of specialty metals, Huaxiao Metal offers this in-depth guide to help you understand what C3-80 is, what its properties are, how it can be processed, and what its applications are.
What is the Material of C3-80 Stainless Steel?
C3-80 product material belongs to martensitic stainless steel, tensile strength of 800 Nm / mm3, C3-80 just means mechanical properties. This product involves raw materials, forging mode (red forging or cold heading), cooling mode (oil cooling, water cooling, air cooling), cleaning mode, heat treatment mode (vacuum heat treatment, box heat treatment, belt heat treatment), CNC turning, rolling teeth (rolling machine, rolling wheel), etc., a link does not do a good job may cause a chain reaction of the product (broken head, broken rods, rotten teeth, etc.).
If you are looking for a reputable manufacturer to supply C3-80 steel plates, bars, round bars, forgings, cut or specially machined parts, please contact Huaxiao Metal for the latest prices and inventory.
C3-80 Equivalent Steel Grades
| Country / Standard | Equivalent Grade |
|---|---|
| China | 40Cr (approximate) / 42CrMo (similar properties) |
| USA | AISI 4140 / SAE 4140 |
| Germany | 42CrMo4 |
| Japan | SCM440 |
| ISO | 42CrMo4 |
Note: C3-80 is a specific industry-defined grade, with properties similar to but not entirely equivalent to 42CrMo. Please contact us directly for specific alternatives.
C3-80 Technical Specifications
For professionals, accurate technical data is paramount. The properties of C3-80 class fasteners are governed by international standards to ensure consistency and safety.
Governing Standard: ISO 3506-1:2020
The primary standard defining this property class is ISO 3506-1:2020, “Fasteners — Mechanical properties of corrosion-resistant stainless steel fasteners — Part 1: Bolts, screws and studs”. This standard sets the required chemical composition and mechanical properties.
Chemical Composition (%)
The chemical composition for steel used to produce C3-80 class fasteners must fall within these ranges:
| Element | Symbol | Content (%) |
| Carbon | C | 0.11 – 0.20 |
| Chromium | Cr | 15.00 – 18.00 |
| Nickel | Ni | 1.25 – 2.50 |
| Silicon | Si | ≤ 1.00 |
| Manganese | Mn | ≤ 1.00 |
| Phosphorus | P | ≤ 0.040 |
| Sulfur | S | ≤ 0.030 |
Note: This composition is typical of steel grades like AISI 431 (1.4057), which are often used to achieve the C3-80 property class.
Mechanical Properties (at room temperature)
The defining feature of C3-80 is its mechanical strength, achieved after hardening and tempering.
| Property | Value |
| Tensile Strength (min.) | 800 MPa |
| Stress at 0.2% Proof Load (min.) | 640 MPa |
| Elongation after Fracture (min.) | 0.4d (where d is the nominal diameter) |
| Hardness (Rockwell) | ~ 23 – 35 HRC |
Why does C3-80 achieve such high performance?
The high strength and good toughness of C3-80 are attributed to its precise Cr-Mo alloying design. Chromium and molybdenum form fine, dispersed phases, which effectively enhance precipitation strengthening during heat treatment, while simultaneously ensuring the structural stability of the steel within the critical temperature range.
Heat Treatment Process for C3-80
Achieving the “80” class strength requires a precise heat treatment process. This typically involves:
Hardening (Quenching): Heating the steel to a temperature of 950-1050°C and then rapidly cooling it in oil. This creates a hard, brittle martensitic structure.
Tempering: Reheating the hardened steel to a lower temperature, typically between 200-350°C, and then air-cooling it. This process reduces brittleness and develops the final desired balance of strength and toughness.
Key Applications of C3-80
Thanks to its robust profile, fasteners and components made to the C3-80 class are trusted in a wide range of critical industries:
Petrochemical Industry: For valves, pumps, and flanges requiring high strength.
Wind Power Generation: In the assembly of wind turbines and towers.
Nuclear Power Facilities: For critical, non-structural applications.
Railway and Aerospace: In high-stress components and structural bolts.
Marine Engineering: For propeller shafts and other high-strength fittings.
Manufacturing: Production of high-strength shafts, piston rods, and pumps.
Looking for C3‑80 stainless steel stock or ready-to-use components? Send us your specifications and we’ll provide a tailored solution.
C3‑80 Manufacturing & Processing Techniques
Producing C3‑80 stainless steel involves several key processes to ensure optimal mechanical properties and dimensional accuracy:
1. Forging or Bar Machining
C3‑80 is typically forged or machined from high-purity martensitic stainless steel billets. Precise forging ensures uniform grain structure and improves strength.
2. CNC Machining
After forging, the material is precision-machined using CNC turning and milling equipment to meet dimensional tolerances and surface finish requirements.
3. Heat Treatment
C3‑80 is known for its response to heat treatment:
Quenching: Rapid cooling in oil or air to harden the structure.
Tempering: Reheating at lower temperatures to relieve internal stress and optimize toughness.
This combination delivers superior wear resistance, ideal for tooling and structural components.
Looking for C3‑80 stainless steel stock or ready-to-use components? Send us your specifications and we’ll provide a tailored solution.
What Material is C3?
C3 is ordinary carbon structural steel C class steel old model, A class to ensure the mechanical properties, B class to ensure the chemical composition, C that is to ensure the mechanical properties also guarantees the chemical composition.
C3 is the United States ansi grade, equivalent to iso k10, domestic YG6X, tungsten and cobalt tungsten carbide steel.
C3‑80 vs Other Martensitic Stainless Steels
| Grade | Hardness | Corrosion Resistance | Typical Use |
|---|---|---|---|
| C3‑80 | Very High | Moderate | Tools, precision parts |
| 410 | Medium | Moderate | Cutlery, pumps |
| 420 | High | Good | Surgical instruments |
| 440C | Very High | Good | Bearings, blades |
| 17‑4PH | High (after aging) | High | Aerospace, nuclear |
Compared to common grades like 410 or 420, C3‑80 offers higher hardness and better strength, making it ideal for custom-machined wear-resistant parts.
Why Choose Huaxiao Metal for Your C3-80 Material Needs?
At Huaxiao Metal, we provide:
Forged bars and billets
Custom CNC-machined components
Heat-treated parts according to your specifications
Global shipping with reliable lead times
Ready to source C3‑80 stainless steel today? Contact Huaxiao Metal to get an instant quote or free consultation.
FAQ
Is C3‑80 stainless steel corrosion resistant?
Yes, C3‑80 offers moderate corrosion resistance, better than carbon steel, but less than austenitic grades like 304 or 316.
Can C3-80 steel be welded? What precautions should be taken when welding?
C3-80, as an alloy steel, can be welded, but strict preheating and post-weld treatment procedures must be followed. It is recommended to use low-hydrogen welding materials. Preheating to 150℃-300℃ is necessary before welding, and stress-relieving heat treatment (such as tempering) should be performed immediately after welding to prevent cold cracking in the weld zone.
What is the heat treatment process for C3‑80?
Typical process involves quenching at ~1050°C followed by tempering at 200–350°C, which achieves hardness levels up to 58 HRC.
What are typical dimensions available?
We offer bars, rods, and custom-machined parts based on your drawings or standards. Contact us for stock availability.
What is the highest hardness that C3-80 can achieve?
With proper quenching and low-temperature tempering, C3-80 can reach a Rockwell hardness of approximately 48 HRC. The specific maximum hardness depends on the carbon content and heat treatment parameters. Please inform us of your usage environment, and we will recommend the optimal target value for your heat treatment process.
Besides C3-80, what other similar alloy steel grades does Huaxiao Metal offer?
Huaxiao Metal specializes in supplying various high-performance special steels and alloys. If you require higher strength/corrosion resistance, we can provide grades such as C4-90, 4340, and D2/SKD11 (high wear-resistant die steel). Our experts can recommend the most suitable C3-80 replacement or upgrade material based on your working conditions.
Conclusion
C3‑80 is a premium martensitic stainless steel that delivers exceptional hardness and wear resistance, making it ideal for high-performance industrial applications. If you’re looking for a trusted supplier with machining, forging, and heat treatment capabilities, Huaxiao Metal is here to help.
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