Stainless
Stainless 348
Annealing Procedure
1850-2000 F (1010-1093 C), water quench. This procedure will result in maximum ductility. For maximum corrosion resistance, see the note on stabilizing anneal under corrosion.
Applications
348 has low tantalum and cobalt and is employed in a variety of nuclear applications.
Cold Workability
Although this material requires higher initial forces than 304 stainless, it is quite tough and ductile and can be readily stamped, blanked, spun and drawn.
Hardening Procedure
This alloy does not harden by heat treating. Elevated properties may only be obtained through cold reduction.
Hot Workability
Working temperatures of 2100-2250 F (1149-1232 C) are recommended for forging, upsetting and other hot work processes. Do not work this alloy at temperatures below 1700 F ( 927 C). Material must be water quenched or fully annealed after working to reattain maximum corrosion resistance.
Machinability
Slightly tougher than 304 stainless, this material will produce the same tough stringy chips. The use of slow speeds and constant positive feeds will minimize this alloy's tendency to work harden.
Principle Design Features
Similar to 321 stainless, 348 uses columbium/ tantalum as stabilizing elements to maximize its principal feature: resistance to intergranular corrosion. It can be used in applications requiring repeated heating in the range of 800 and 1650 F (427-899 C).
Weldability
348 may be welded by all commonly used fusion and resistance methods. Oxyacetylene welding is not recommended. When necessary, use AWS E/ER348 filler metal.
Known Forms
Angle
Channel
Coil
Disc
Flat Bar
Foil
Hexagon Bar
Hollow Bar
Pipe
Plate
Precision Ground Bar
Rectangle Tube
Ring
Rod
Round Bar
Round Tube
Sheet
Square Bar
Square Tube
Standard Beam
Strip
Tee
Additional Data
Specifications
348,A167,A182,A213,A240,A249,A269,A276,A312,A314,A336,A358,A376,A403,A409,A479,A580,A632,A813,A814,1.4550,S-23195,S766,S34800Chemical Elements
| Carbon | 0.08 max |
| Chromium | 17 - 19 |
| Cobalt | 0.2 max |
| Iron | Balance |
| Manganese | 2 max |
| Nickel | 9 - 13 |
| Niobium+Tantalum | Min:10 x C |
| Phosphorus | 0.045 max |
| Silicon | 1 max |
| Sulphur | 0.03 max |
| Tantalum | 0.1 max |
Physical Properties
Density: 0.29lb/in³
Electrical Resistivity: 438µΩ·cm
Melting Point: 2600°F
Specific Gravity: 8.03
Specific Heat: 0.12BTU/lb·°F
Mechanical Properties
Modulus of Elasticity – Tension: 28MSI
Thermal Conductivity
| Condition | Temperature | Conductivity |
|---|---|---|
| Annealed | 212 °F | 11.2 BTU/hr·ft·°F |
| Annealed | 932 °F | 15.4 BTU/hr·ft·°F |
Thermal Expansion
| Condition | Min | Max | Expansion Coefficient |
|---|---|---|---|
| Annealed | 32 °F | 600 °F | 9.5 μin/in·°F |
| Annealed | 32 °F | 1000 °F | 10.3 μin/in·°F |
| Annealed | 32 °F | 1500 °F | 11.1 μin/in·°F |