2. AISI 316, 316L, 317
Why Ni ?
Austenite stabilizer
Provides great toughness and high strength
Improves resistance to oxidation and corrosion
Increases toughness at low temperatures
But
Detrimental to the human body
Carcinogen
Medical implants, dental materials
Nickel Containing Stainless Steels
3. Nickel Free Stainless Steel
Grade No. C Mn P S Si Cr Ni
AISI 403 0.15 1.0 0.040 0.03 0.50 11.5~13.0 --
AISI 405 0.08 1.0 0.040 0.03 1.00 11.5~14.5 --
AISI 409 0.08 1.0 0.045 0.045 1.001 0.5~11.75 --
AISI 410 0.15 1.0 0.040 0.03 1.00 11.5~13.5 --
4. Nickel-free ferritic or martensitic stainless
steels
Ferromagnetic and have poor ductility
Nickel-free austenitic stainless steel
Non-ferromagnetic
Nickel replaced by either nitrogen or manganese
or both
5. Ni to be substituted
Nitrogen
â—‹ A strong austenite forming element
â—‹ Successfully used to replace nickel
â—‹ Develop low-nickel or nickel-free austenitic
stainless steels.
Ni Free Stainless steel
6. Chromium, Molybdenum and Nitrogen
Corrosion-resistant nickel-free austenitic stainless
steel
High-Nitrogen Stainless Steels
High strength
â—‹ Interaction/pinning between dislocations and interstitial
nitrogen atoms
â—‹ Large lattice distortion associated with interstitial
nitrogen
Show high work-hardening rates
Good high-temperature mechanical properties
Properties of HNS
7. CHEMICAL COMPOSITION
C- 0.20 Cr- 18.0-23.0 Si-1.00 Mn-1.00 P-0.040 S-0.030 Fe balance
HEAT TREATMENT OF STAINLESS 442
Anneal by heating to 1300°F (704°C), then air cool or water
quench
Thermal treatment won’t harden
APPLICATIONS OF STAINLESS 442
Storage tanks for nitric acid
Zinc die casing machines
Furnace and combustion components
Decorative trim
MACHINABILITY OF STAINLESS 442
Lower work-hardening rate than iron-chromium-nickel varieties
Carbide and high-speed steel tools appropriate
Lubrication and thorough cooling are critical
STAINLESS STEEL 442
8. ANNEALING
Soak at 1200-1400 F(649-760 C), air cool.
HARDENING
Does not respond appreciably to heat treatment
Soaking at 1800-1850 F(982-1010 C) followed by oil
quenching will increase mechanical properties.
MACHINABILITY
Soft and ductile
Easily machined using standard practices
STAINLESS STEEL 405
9. Furnace components
Ladles used in molten nonferrous
applications
Stirring rods
Hazardless body implants
Dental material
turbine parts and compressor blades.
APPLICATIONS OF Ni FREE
STAINLESS STEEL
10. Lang Y, Zhou Y, Rong F, Chen H, Weng Y, Su J and
Dong H 2009 High Nitrogen Steels Conf. Proc.,
HNS2009 p 195
Lang Y, Zhou Y, Rong F, Chen H, Weng Y, Su J and
Dong H 2009 High Nitrogen Steels Conf. Proc.,
HNS2009 p 195
V.G. Gavriljuk and H. Berns: High Nitrogen Steels,
Springer-Verlag, Berlin, 1999, 1.
REFERENCE