SS 420
SS 420 is a heat treatable martensitic chromium stainless steel. Melt practice is controlled to develop a surface nearly free from defects. It provides the best combination of wear resistance and corrosion resistance, and is used in demanding medical accessories.

NOMINAL COMPOSITION:

Chromium 12.5%
Nickel .20%
Manganese .50%
Carbon .22%
Silicon .50%
Iron Balance
SS 420 PHYSICAL PROPERTIES:
Density - 0.28 lbs/cu.in.
Melting Point (Approx.) - 1460° C
Electrical Resistivity @ R.T. - 55 Microhm· cm
Thermal Expansion Coefficient - 10.3 x 10-6/°C (0° TO 100° C)
Thermal Conductivity @ 100° C - 24.9 W/m· K
Magnetic Attraction - Yes 

GENERAL INFORMATION:
The alloy can be cold formed from the annealed temper. Welding should be accomplished by pre and post heating. Pre-heating at 450° F and post-heated at 1300° F will prevent cracking. The corrosion resistance is optimized in the heat treated temper and assured by passiviation. It is resistant to water and organic materials. Oxidation resistance remains favorable in most applications up through 1200°F.

AVAILABILITY:

SS 420 is available from Hamilton Precision Metals as strip product from .001” to .060” in widths up to 12.0”. The material conforms to UNS S42000.