Type 440A (UNS S44002)

Description

Type 440A is a corrosion resistant martensitic stainless steel containing approximately 17% chromium offering a wide range of mechanical properties through heat treatment. This grade offers the superior wear resistance of high carbon steel with the corrosion resistance of a stainless steel. The optimum corrosion and hardness are obtained in the hardened and hardened and tempered condition. Type 440A is used for cutlery applications as well as dental and surgical instruments and is magnetic in both the annealed and heat-treated conditions.

Chemical Composition
Chemical Composition (wt%) limits for Type 440A stainless steel*
Element 440A
Carbon 0.60-0.75
Chromium 16.0-18.0
Molybdenum 0.75
Nickel 0.50
Manganese 1.00
Silicon 1.00
Phosphorus 0.040
Sulfur 0.030
* Maximum, unless range is indicated
Mechanical Properties
Typical mechanical property requirements for annealed product
Property 440A
Yield Strength, min. (ksi) 60-62
Tensile Strength, min. (ksi) 65
Elongation, min. (%) 20
Hardness, max. (Rb) 95-96
Physical Properties
Physical properties for Type 440A stainless steel
Property 440A Data
Density, lb/in3 0.280
Modulus of Elasticity, psi 29.0 x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 5.6 x 10-6
Thermal Conductivity, Btu/ft hr ˚F

14.0

Specific Heat, Btu/lb ˚F 0.11
Electrical Resistivity, Microohm-in 23.6
Standards
Typical standards for Type 440A stainless steel
440A
ASTM A276

Data are typical, are provided for informational purposes, and should not be construed as maximum or minimum values for specification or for final design, or for a particular use or application. The data may be revised anytime without notice. We make no representation or warranty as to its accuracy and assume no duty to update. Actual data on any particular product or material may vary from those shown herein.  © 2014 RMP Inc. All rights reserved.