420 stainless steel is a high-carbon steel with a minimum chromium content of 12%. Like any other stainless steel, grade 420 can also be hardened through heat treatment. It offers good ductility in its annealed state and excellent corrosion resistance properties when the metal is polished, surface grounded or hardened. This grade has the highest hardness - 50HRC - among all the stainless steel grades with 12% chromium.

420 Stainless Steel strip Characteristic machining technology

Some of the key properties of 420 stainless steel include:

– Good corrosion resistance

– High strength

– Easy to clean

MACHINEABILITY AND WELDABILITY

Machinability is rated at 30% of B1112. Similar to machining high-carbon, high-chromium tools steels, but 420 creates tough, stringy chip buildup.

420 stainless is not commonly welded due to its air hardening characteristics. Welding may be performed after preheating to 300°-400°F with post weld tempering at temperature for 2 hours.

420 can be hot worked by slowly bring temperature to 1400° F, then on to 2000°-2200°F.Reheat often to keep the temperature above 1600°F. After working, cool in furnace slowly to avoid cracking. 420 will withstand only minor cold working. Radical forming operations will result in cracking.

HEAT TREATING

Hardening range is between 1850° and 1950° F. Quench in heated oil. Temper to required hardness.

Standard Specification Of 420 Stainless Steel strip

Chemical Composition

Carbon:                  0.15% (Min)

Manganese:            1.00% (Max)

Silicon:                   1.00% (Max)

Phosphorous:           0.04% (Max)

Sulfur:                    0.03% (Max)

Chromium:               12%-14%

Application

Construction/Indutry/Building/Chemical/Auto

Stainless steel is used to make consumer goods, including domestic kitchen supplies and tableware, sinks, laundry equipment, flatware and electric appliances and in the food and beverage industry to make silos, vats, kegs and large kitchen equipment.

Stainless steel is also found in the construction and engineering industries as roofing, gutters, elevator doors, public seating and is used to build large skyscrapers. Automotive parts, bus frames, pipes, valves, pumps and industrial mixers are also often made out of stainless steel.