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440 Stainless Steel

440 stainless steel, also commonly referred to as “razor blade steel,” is a type of hardenable high-carbon chromium steel. This alloy is known for its exceptional hardness and ability to hold a sharp edge, making it a popular choice for razor blades and other cutting tools.

4140 stainless steel

420 Stainless Steel

440 Stainless Steel, also as known as “razor blade steel,” is hardenable high-carbon chromium steel.

One of the unique characteristics of 440 stainless steel is its ability to undergo heat treatment to achieve varying hardness levels.

This gives OEMs the ability to alter the alloy’s properties to meet the unique requirements of their application.

After being strengthened using this method, type 440 steel becomes the hardest stainless steel.

Type 440 steel excels in high-stress settings because of its superior wear and corrosion resistance and high carbon content.

Due to its simplicity in machining, it is the best option for the fabrication of intricate objects.Type 440 steel, which combines strength, toughness, and hardness, is regarded as a top-performing alloy in a variety of industries.

440 Stainless Steel Properties and Specifications

440 offers good corrosion resistance along with abrasion resistance. All grades can be easily machined in their annealed state, they also offer resistance to mild acids, alkalis, foods, fresh water, and air. Type 440 can be hardened to Rockwell 58 harness.

  • 440 stainless steel is hardenable high-carbon chromium steels designed to provide stainless properties with maximum hardness.
  • Have maximum hardness together with high strength and corrosion resistance in the hardened and stress relieved condition.
  • Always used in the hardened or hardened and stress relieved conditions.
  • None of the alloys has its full corrosion resistance either in the annealed or in the hardened and tempered condition.
  • Wide applications where good corrosion resistance along with high hardness or abrasion resistance is required.

Type 440 Stainless Steel is available in:

  • Bar
  • Wire
  • Billets

The following specifications are generally applicable:

Sheets and Plates

  • AMS 5630C
  • ASTM A276-67
  • ASTM A314-63
  • ASTM A-580-67
  • QQ-2-763D
  • MIL-S-862B

What is 440 Stainless Steel?

High-carbon chromium steel alloy 440 stainless steel is renowned for its excellent toughness and capacity to maintain a sharp edge, this has earned it the term ‘razor steel’.

As a result, it is a preferred option for ball bearings, valve components, surgical and dental equipment, woodworking tools, razors, and blades.

440 is especially known for having a lot of strength and tenacity, making it the go-to steel for use in high-stress situations.

Its high carbon content offers it good wear resistance and corrosion resistance, and it may be heat treated to varied levels of hardness.

It is a preferred choice for intricate parts and components in many sectors and industries since it is relatively simple to process.

History of 440 Stainless Steel

The 1940s saw what could be termed ‘the 440 stainless steel era‘ with the 440A, the first grade of 440, being created as a more effective substitute for the conventional 304 and 316 grades of stainless steel that were in popular use. The 440A grade was renowned for its excellent resistance to corrosion and capacity to maintain a sharp edge, hence the name ‘razor steel’.

The 440B and 440C grades, which have a higher carbon content, were created in the years that followed to offer even more strength and wear resistance. These grades were employed in a wide range of products, including cutlery, medical equipment, ball bearings, and more.

Due to its remarkable performance qualities, the 440 series of stainless steel immediately gained popularity and it was widely employed in the production of a range of products.

Applications for 440 Stainless Steel

440 stainless steel, also known as “razor blade steel,” is a versatile and highly sought-after alloy due to its exceptional hardness and ability to hold a sharp edge. It also has excellent corrosion resistance and high strength and toughness, which makes it suitable for a wide range of applications, particularly in the aerospace, automotive, and medical industries.

With the ability to tailor its properties through heat treatment, it can also be used in a variety of different applications, including manufacturing complex parts and components.

Knife making

Due to its superior qualities for maintaining an edge and resisting corrosion, 440 steel is a common material choice for producing knives. It is frequently employed for expensive pocket knives, hunting knives, and culinary knives.

Surgical instruments

The steel is also used in the manufacture of surgical instruments due to its ability to resist corrosion and maintain a sharp edge. Its non-magnetic properties also make it suitable for use in MRI and other medical equipment.

Oil and Gas

440 stainless steel is frequently used in the oil and gas industries, at every level of production, to produce bearings and valve parts. Because of its great corrosion resistance, it can be used in the harshest of environments.

Aerospace and Automotive

Type 440 is also extensively used in both the aerospace and automotive industries, where it is used for several applications due to its strength and durability. It is often used in the manufacture of gears, shafts and other high-stress components.

Sporting goods

440 stainless steel is commonly used in the manufacturing of sporting goods, especially those that require durability and corrosion resistance. Golf clubs, fishing reel parts, and even skateboard trucks are some examples where 440 stainless steel is used.

Industrial equipment

Various industrial equipment is also manufactured out of 440. It is suitable for use in pumps, valves, and other machinery that may be exposed to hostile conditions because of its high strength and resistance to corrosion.

Composition & Properties

Property

Type 440C

Carbon

.95 – 1.2

Manganese

1.25 max

Silicon

1.00 max

Phosphorus

.04 max

Sulfur

.04 max

Chromium

16.5 – 18.0

Molybdenum

75 max

Nickel

NA

Mechanical Properties

Properties

Annealed

Hardened & Stress Relieved

Ultimate Tensile Strength (psi)

110,000

285,000

0.2% Yield Strength (psi)

65,000

275,000

Elongation (% in 2?)

14

2

Reduction in area (%)

25

10

Rockwell Hardness

B97

C57

Impact Strength (Izod, V-Notch) [ft-lbs]

NA

1-5