What is SUS440A(UNS S40022) stainless steel?
Alloy 440A is a high carbon straight chromium martensitic stainless steel. It combines the superior wear resistance of high carbon alloys with the excellent corrosion resistance of chromium stainless steels. It is magnetic in both the annealed and hardened conditions. Maximum corrosion resistance is attained only in the fully hardened condition.
UNS 440A comprehensive description:
440A stainless steel with long lasting protection of corrosion resistance is the surface substrate material. It requires no additional system, in order to protect the base metal, the metal itself will continue. Stainless steel products to complete its service life. Due to the raw material is 100% recyclable, have focused on processing. In fact, more than 50% of new stainless steel stainless steel scrap from down, thus completed the full life cycle is used again. So, in the project life cycle is stainless steel, is often the most valuable choice.
UNS 440A heat treatment process
1) annealing, 800 -920 degree slow cooling.
2) quenching, 1010 - 1070 degree oil cooling;
3) tempering, 100 -180 degree cold fast..
UNS 440A scope of application:
Mainly used in the manufacture of the corrosion environment and no lubrication bearing working parts in strong oxidizing atmosphere. S44002 has good temperature resistance; high temperature size so can also be used as corrosion resistant high temperature bearing steel. In addition, can also be used to manufacture high quality tools, such as medical scalpel, scissors,nozzle, bearings, etc. 440 f, is to improve the performance of S44002 steel free cutting steel, used for automatic lathe, as well as ordinary alloy steel by quenching hardening characteristics, thus can be obtained by selecting the brand and heat treatment conditions to wide range of different mechanical properties. SS44002 under dynamic load capacity is low.Stainless steel UNS S44002 can be produced as S44002 stainless steel plates, S44002 stainless steel bar, S44002 stainless steel wire, S44002 stainless steel forging product
Additional information:
I. Related features
Higher hardness and moderate wear resistance, in grinding, its disadvantage is relatively large viscosity, and heating up quickly. It is recommended to use chrome corundum or microcrystalline corundum grinding wheel for grinding.
The annealing temperature of 440C is very low. For heat treatment of tools and bearings, the recommended hardness is HRC57-59. If cryogenic treatment is carried out, the hardness can reach HRC60. Corrosion resistance and toughness are very strong, now more widely used in hand knives and high quality factory tools.
Second, related applications
In the domestic stainless steel grade, 440C has a higher hardness. It is mainly used to manufacture bearing parts working in corrosive environment and strong oxidizing atmosphere without lubrication. 440C can also be used as corrosion resistant high temperature bearing steel because of its good size and temperature.
In addition, it can also be used to manufacture high quality knives, such as medical scalpels, scissors, nozzles, bearings and so on. 440F: improves the cutting performance of 440C steel, used in automatic lathes, Martensite stainless steel and ordinary alloy steel have the same characteristics of hardening through quenching, so by choosing grades and heat treatment conditions to get a wide range of different mechanical properties. The capacity of 440C to bear dynamic load is low.
Strip, Coil, Foil, Wire, ASTM A 276
APPLICATIONS
Cutlery
Scissors
DESCRIPTION
Type 440A is a straight chromium martensitic stainless steel which combine the superior wear resistance of high carbon alloys with the excellent corrosion resistance of chromium stainless steels. It is magnetic in both the annealed and hardened conditions. Maximum corrosion resistance is attained only in the fully hardened condition.
CHEMISTRY TYPICAL
Carbon: 0.60-0.75
Manganese: 1.00 max
Phosphorus: 0.04 max
Sulfur: 0.03 max
Silicon: 1.00 max
Chromium: 16.00-18.00
Molybdenum: 0.75 max
Iron: Balance
PHYSICAL PROPERTIES
Density: 0.28 lbs/in3 7.74 g/cm3
Electrical Resistivity: microhm-in (microhm-cm):
68 ° F (20 ° C): 23.7 (60.0)
Specific Heat: BTU/lbl° F (kJ/kg•K):
32 - 212 ° F (0 - 100 °C): 0.11 (0.46)
Thermal Conductivity: BTU/hr/ft2/ft/° F (W/m•K):
At 212 ° F (100 ° C): 14.0 (24.2)
Mean Coefficient of Thermal Expansion: in/in/° F (µm/m•K)
32 - 212 °F (0 - 100 °C): 5.7 x 10·6 (10.2)
32 - 1200 °F (0- 649 °C): 6.8 x 10·6 (12.1)
Modulus of Elasticity: ksi (MPa)
29 x 103 (200 x 103) in tension
Magnetic Permeability: Magnetic
FORMS
Coil - Strip, Foil, Ribbon Wire - Profile, Round, Flat, Square
MECHANICAL PROPERTIES AT ROOM TEMPERATURE ANNEALED TYPICAL
Ultimate Tensile Strength: 100 KSI max (690 MPa max)
Yield Strength (0.2% Offset): 65 KSI max (448) MPa max)
Elongation: 15% min
Hardness: Hv 256 max: gauges: < 0.010 inches Rb 100 max: gauges:> 0.010 inches
TEMPERED
Type 440A can be cold rolled to various tempers. Contact Ulbrich Technical Services for additional information.
ADDITIONAL PROPERTIESCORROSION RESISTANCE
Type 440A provides full corrosion resistance only in the hardened or hardened and stress-relieved conditions. Type 440A has good corrosion resistance to atmosphere, fresh water, foods, alkalies and mild acids.
FINISHES
# 1 - Hot rolled annealed and descaled. It is available in strip, foil and ribbon. It is used for applications where a smooth decorative finish is not required.
# 2D - Dull finish produced by cold rolling, annealing and descaling. Used for deep drawn parts and those parts that need to retain lubricants in the forming process.
# 2B - Smooth finish produced by cold rolling, annealing and descaling. A light cold rolling pass is added after anneal with polished rolls giving it a brighter finish than 2D.
#BA- Bright annealed cold rolled and bright annealed
#CBA- Course bright annealed cold rolled matte finish and bright anneal
#2 - Cold Rolled
# 2BA- Smooth finish produced by cold rolling and bright annealing. A light pass using highly polished rolls produces a glossy finish. A 2BA finish may be used for lightly formed applications where a glossy finish is desired in the formed part.
Polished - Various grit finish for specific polish finished requirements.
* Not all finishes are available in all alloys - Contact LYMETAL Sales for more information.
WIRE FINISHES
XC - Extra clean bright annealed or bright annealed and cold rolled Grease - Ultra-bright finish (for decorative applications) Soap - Soap is not removed from tempered wire to act as a lubricant.
* Contact LYMETAL for custom wire finishes.
COLD FORMING
Type 440A has limited formability in the annealed condition.
HEAT TREATMENT
Hardening: Type 440A can be hardened cold working and by heat treatment. Contact LYMETAL Technical Service for additional information.
If you need product information or price, please fill in your contact information in the form below, we will usually contact you within 12 hours. You could also email me info@lyapm.com to get prompt reply.
NO.501 Dongshe Road, Dongjing Town, Songjiang District, Shanghai,China,201600
. 
Mobile/Whatsapp/Zalo/Lines/Skype
General Inquiry
company profile download