Typical Applications
| Specified for a wide variety of applications
where good corrosion and hardness in the range of
C50 to C54 is required |
| Applications include cutlery, surgical
and dental instruments, scissors, tapes and straight
edges, gauges, needle valves, ball check valves, gear
shafts, cams, pivots, ball bearings and hand tools |
| Not normally used at temperatures
exceeding 800° F due to rapid softening and loss
of corrosion resistance |
Machinability
Type 420 Stainless Steel machines like a high carbon
steel. Chips are tough and stringy. Carbide cutting tools
are recommended because this alloy has an abrasive action
on tools. For parts that require extensive machining,
the two free-machining versions, Type 430 and Type 430F
Se offer fabrication economies.
Weldability
Because of the air hardening characteristics of Type
420, it has only fair weldability and is seldom welded. |
Formability
If annealed for maximum softness, Type 420 can be moderately
cold formed, and cold headed. It can be readily forged
and hot-headed. Preheating prior to hot working
insures the best results. Because this steel is
air hardening, all hot worked parts should be furnace
cooled to prevent cracking.
Corrosion Resistance
Type 420 has its full corrosion resistance only in the
hardened or hardened and stress relieved conditions. In
these conditions its corrosion resistance is similar to
Type 410. Type 420 resists corrosion by the atmosphere,
fresh water, mine water, steam, carbonic acid, crude oil,
gasoline, perspiration, alcohol, ammonia, mercury, sterilizing
solutions, soaps, and other similar corrosive media.
Heat Treatment
ANNEALING: For maximum softness, heat uniformly to 1600-1650°
F and cool down slowly in the furnace.
HARDENING: Preheat, then heat to 1800-1950° F, soak
at temperature and air cool or quench in warm oil.
STRESS RELIEVING: Heat at 300-800° F for 1 to
3 hours, cool in air or quench in oil or water. |
