Call Us Today! +86-13761906384

420 vs 304 Stainless Steel: A Complete Comparison to Make the Right Choice

420 vs 304 Stainless Steel A Complete Comparison to Make the Right Choice

420 vs 304 Stainless Steel: A Complete Comparison to Make the Right Choice. Choosing the right stainless steel for your project is one of the most critical decisions you’ll make. It impacts performance, longevity, and cost. Two of the most common yet fundamentally different grades are 420 and 304 stainless steel. But how do you know which one is the right fit for your application?

As a leading stainless steel supplier, we at Huaxiao Metal often help our clients navigate this choice. This guide will break down the key differences between 420 and 304 stainless steel, so you can make an informed decision with confidence.

What Is 420 Stainless Steel?

420 stainless steel is a martensitic stainless steel, which can be hardened through heat treatment, much like carbon steel. Its high carbon content is the secret to its signature feature: exceptional hardness and wear resistance.

Key Properties:

  • High Hardness: After heat treatment, 420 steel can achieve a high Rockwell hardness, making it ideal for applications requiring a sharp edge and high strength.
  • Good Wear Resistance: It holds up well against abrasion and friction.
  • Moderate Corrosion Resistance: It offers good resistance in mild atmospheric conditions, fresh water, and when free of contaminants. However, it is susceptible to rust in marine or chemical environments.

Best For: Applications where hardness is the most critical factor.

  • Cutlery and Knives
  • Surgical and Dental Instruments
  • Valves and Pump Shafts
  • Plastic Molds and Dies

Need a material that is tough and holds a sharp edge? Explore Huaxiao Metal’s range of 420 Stainless Steel Plate, Coil, and Bar products.

  • Grade: AISI 420 / UNS S42000
  • Chromium content: 12–14%
  • Carbon content: ~0.15%–0.40%
  • Magnetic: Yes
  • Hardenable by heat treatment: Yes
  • Finish options: 2B, BA, polished, etc.

What Is 304 Stainless Steel?

304 stainless steel is the most versatile and widely used stainless steel in the world, often referred to as “18/8” because of its composition of 18% chromium and 8% nickel. It belongs to the austenitic family.

Key Properties:

  • Excellent Corrosion Resistance: The nickel content gives 304 superior resistance to rust and a wide variety of chemical corrodents. This is its most significant advantage.
  • Superb Formability & Weldability: It is highly ductile and can be easily bent, stamped, and drawn without cracking.
  • Hygienic and Easy to Clean: Its non-porous surface makes it a standard in the food and medical industries.

Best For: Applications where corrosion resistance and formability are paramount.

  • Food Processing Equipment
  • Kitchen Sinks and Appliances
  • Architectural Paneling and Railing
  • Chemical Containers and Piping

Looking for a reliable, all-around performer for corrosive environments? Check out our inventory of 304 Stainless Steel Sheets, Coils, Strips, etc.

  • Grade: AISI 304 / UNS S30400
  • Chromium: 18–20%
  • Nickel: 8–10.5%
  • Carbon: Max 0.08%
  • Magnetic: No (in annealed condition)
  • Not heat-treatable for hardness

420 vs 304 Stainless Steel: Key Differences

For a quick overview, here is a simple comparison table:

Feature420 Stainless Steel304 Stainless Steel
Steel FamilyMartensiticAustenitic
Key FeatureHigh Hardness, Wear ResistanceExcellent Corrosion Resistance, Formability
Corrosion ResistanceModerateExcellent
HardnessVery High (Heat-treatable)Soft (Not heat-treatable)
MagnetismMagneticNon-magnetic (in annealed condition)
Common ApplicationsKnives, Surgical Tools, Valves, ShaftsKitchen Sinks, Food Processing, Architecture
CostGenerally lowerHigher (due to Nickel content)

Chemical Composition: 420 vs 304 Stainless Steel

Element420 Stainless Steel304 Stainless Steel
Chromium (Cr)12.0 – 14.0%18.0 – 20.0%
Nickel (Ni)≤ 1.0% (often none)8.0 – 10.5%
Carbon (C)0.15 – 0.40%≤ 0.08%
Manganese (Mn)≤ 1.0%≤ 2.0%
Silicon (Si)≤ 1.0%≤ 1.0%
Phosphorus (P)≤ 0.04%≤ 0.045%
Sulfur (S)≤ 0.03%≤ 0.03%

Mechanical Properties Comparison

Property420 Stainless Steel304 Stainless Steel
Tensile Strength (MPa)650 – 850 MPa (hardened)~520 – 750 MPa
Yield Strength (MPa)345 MPa (typical)~215 – 275 MPa
Elongation (%)~20%~40 – 45%
Hardness (Rockwell HRC)Up to 50 HRC (after heat treatment)~70 HRB (non-hardened)
Impact ToughnessLowHigh

Physical Properties Comparison

Property420 Stainless Steel304 Stainless Steel
Density (g/cm³)7.758.0
Melting Point (°C)~1,480°C~1,400 – 1,450°C
Thermal Conductivity (W/m·K)24.916.2
Electrical Resistivity (µΩ·cm)55.072.0
MagneticYes (strong)No (in annealed state)

Corrosion Resistance

  • 304 Stainless Steel: Offers excellent corrosion resistance in most environments, including acidic and chloride-rich conditions. Suitable for marine, food, and chemical processing applications.

  • 420 Stainless Steel: Provides moderate corrosion resistance, suitable for dry or mildly corrosive environments. Not ideal for saltwater or chemical exposure.

💡 If corrosion resistance is your priority, 304 is the better choice.

Weldability and Fabrication

  • 304 Stainless Steel:

    • Excellent weldability using all standard methods (TIG, MIG, etc.)
    • No post-weld heat treatment required
    • Highly formable and easy to fabricate
  • 420 Stainless Steel:

    • Limited weldability, prone to cracking due to high carbon content
    • Pre-heating and post-weld annealing are often required
    • Less formable due to martensitic structure

Choose 304 if your process involves extensive welding or forming.

Cost and Availability

Factor420 Stainless Steel304 Stainless Steel
Raw Material CostLowerHigher (due to Ni)
Processing CostModerate (needs heat treatment)Lower for standard use
Market AvailabilityCommon, less than 304Extremely common, widely stocked
Your Trusted Partner for Both 420 and 304 Stainless Steel
Understanding the differences is the first step. The next step is sourcing high-quality material from a supplier who understands your needs. Huaxiao Metal offers a comprehensive range of 420 and 304 stainless steel products, including plate, sheet, coil, and bar. Our team of experts is ready to provide you with the perfect material for your specific application. Contact us today for a free quote and let us help you move your project forward.

420 vs 304 Stainless Steel: Which is Better for You?

Choose 420 Stainless Steel if:

  • You need extreme hardness and sharpness.
  • Wear resistance is your top priority.
  • Your product will be in a low-corrosion environment.
  • Cost is a primary decision factor.

Choose 304 Stainless Steel if:

  • Superior corrosion resistance is non-negotiable.
  • You need to bend, form, or weld the material.
  • The application is for the food, beverage, or medical industry.
  • You need a non-magnetic material.

Get a Quote from Huaxiao Metal

At Huaxiao Metal, we offer:

  • 420 Stainless Steel: Sheet, coil, strip, bar, rod, etc.

  • 304 Stainless Steel: Sheet, coil, strip, bar, pipe, etc.

  • Custom sizes and surface finishes are available

  • Fast delivery & global shipping

  • Contact us today for competitive pricing!

Why Partner with Huaxiao Metal?

Understanding the technical differences between 420 and 304 stainless steel grades is just the first step. The next, and most crucial, is choosing a supplier you can trust to deliver quality, on time, and on budget.

At Huaxiao Metal, we don’t just sell steel; we build partnerships. Here’s how we deliver unmatched value, by the numbers:

  • 15+ Years of Steel Expertise

    We are not just traders; we are industry veterans. With over 15 years of dedicated experience, our team provides expert technical advice to ensure you select the perfect grade for your application, saving you time and money.

  • 60+ Countries Delivered To

    Our logistics network is truly global. We have a proven track record of successfully exporting to over 80 countries, navigating complex shipping and customs requirements with ease so your material arrives safely and on schedule.

  • 3000,000+ Tons of Ready Stock

    Time is critical. Our massive warehouse holds over 10,000 tons of stainless steel, including extensive stock of 420 and 304 grades in various forms. This means faster dispatch times and shorter lead times for your project.

  • 24-Hour Quotation Promise

    Your time is valuable. Contact our team with your requirements, and we guarantee a detailed, competitive quotation within 24 hours. Experience the efficiency and professionalism that sets us apart.

Ready to Make Your Choice?

Whether your project demands the hard-wearing edge of 420 stainless steel or the superior corrosion resistance of 304, Huaxiao Metal is your definitive source.

Request Your Free Quote Today and let our experts provide the perfect steel solution for you.

Table of Contents

We will answer your email in 24 hours!

Request a Quote

Fill out the form below, and we will be in touch shortly.