1.4571, DIN X6CrNiMoTi17-12-2, AISI 316 Ti

1.4571, DIN X6CrNiMoTi17-12-2, AISI 316 Ti

Designation by Standards

 

Chemical Composition (in weight %)

Description
This austenitic stainless steel has an increased molybdenum and titanium contents to increase its resistance to corrosion when compared to other 300 series alloys. It will resist scaling at higher temperatures and maintains good mechanical properties and ductility.

Applications
PK12SP is used in the construction of apparatus for the chemical and pharmaceutical industries, adn for textile finishing. Component parts for the cellulose, paper, textile, paint, rubber and meat processing industry and for pump components. Steel grade with lower polishability.

Physical properties (avarage values) at ambient temperature
Modulus of elasticity [10³ x N/mm²]: 200, 186 (200^oC), 172(400^oC)
Density [g/cm³]: 7.98
Thermal conductivity [W/m.K]: 15.0
Electric resistivity [Ohm mm²/m]: 0.75
Specific heat capacity[J/g.K]: 0.50

Coefficient of Linear Thermal Expansion 10^{-6 o}C^-1

Hardening
Harden from a temperature of 1020-1120^oC followed by water or air quenching. Structure is austenite with small ferrite component.

Mechanical properties in solution-annealed condition and reistance to intercrystalline corrosion
0.2 % proof stress: 200 N/mm² (for d<=160, 160<d<=250)
1.0 % proof stress: 235 N/mm² (for d<=160, 160<d<=250)
Tensile strength: 500-700 N/mm²
Elongation: 40% (for d<=160, longit.), 30% (for 160<d<=250, transv.)
Notch impact energy (ISO-V): 100 J (for d<=160, longit.), 60 J (for 160<d<=250, transv.) Resistance to interystalline corrosion: yes (in as delivered condition), yes (in sensitised condition)
Note: Sensitisation treatment for 15 min at 700^oC with subsequent cooling in air.

Mechanical Properties At Elevated Temperatures

Forging
Hot forming temperature: 1200-900^oC.

Machinability
Low speeds and constant feeds will minimize this alloy's tendency to work harden. Tougher than 304 stainless with a long stringy chip, the use of chip breakers is recommended.

Corrosion Resistance
Resistant to a wide variety of marine environments, salts, dilute nitric, acetic and sulfuric acids. Owing to teh addition of Ti as carbide former, PK12SP is resistant to intercrystalline corrosion, regardless of thickness and cross-section. Owing to the Mo content, steel displays good resistance to media containing chloride and to non-oxidising acids.

Welding
Good weldability using all processes (except gas welding).

Cold working
Shearing, stamping, heading and drawing can be successfully performed . To remove internal stresses, a post-work annealing is recommended.