Mechanical Properties of
Stainless steel
316
Table 2. Typical mechanical properties
for 316 stainless steel alloys
|
Grade |
316 |
316L |
316H |
316Ti |
|
Tensile Strength
(MPa) |
515 |
520-680 |
520-680 |
485 |
|
Proof Stress 0.2%
(MPa) |
205 |
220 |
205 |
170 |
|
Elongation A5
(%) |
40 |
40 |
40 |
40 |
Physical Properties of
Stainless steel
316
Table 3. Typical physical properties
for 316 stainless steel
alloys
|
Property |
Value |
|
Density |
8.00
kg/m3 |
|
Melting
Point |
1400°C |
|
Modulus of
Elasticity |
193
GPa |
|
Electrical
Resistivity |
0.074x10-6
Ω.m |
|
Thermal
Conductivity |
16.3
W/m.K |
|
Thermal
Expansion |
15.9x10-6
/K |
Alloy Designations
Stainless
steel
316 also corresponds to the following standard designations and
specifications:
|
Euronorm |
UNS |
BS |
En |
Grade |
|
1.4401 |
S31600 |
316S31 |
58H |
316 |
|
1.4404 |
S31603 |
316S11 |
- |
316L |
|
- |
S31609 |
316S51 |
- |
316H |
|
1.4571 |
- |
320S31 |
- |
316Ti |
Corrosion Resistance of
Stainless steel
316
Stainless
steel
316 has excellent corrosion resistance when exposed to a range of
corrosive environments and media. It is usually regarded as “marine grade” stainless
steel but is not resistant to
warm sea water. Warm chloride environments can cause pitting and crevice
corrosion. Grade 316 is also subject to stress corrosion cracking above around
60°C.
Heat Resistance of
Stainless steel
316
Stainless
steel
316 has good resistance to oxidation in intermittent service to 870°C
and in continuous service to 925°C. However, continuous use at 425-860°C is not
recommended if corrosion resistance in water is required. In this instance 316L
is recommended due to its resistance to carbide precipitation.
Where high strength is required at temperatures above 500°C,
grade 316H is recommended.
Fabrication of
Stainless steel
316
Fabrication of all stainless
steels should be done only with tools
dedicated to stainless steel
materials. Tooling and work surfaces must be thoroughly cleaned before
use. These precautions are necessary to avoid cross contamination of stainless
steel by easily corroded
metals that may discolour the surface of the fabricated product.
Cold Working of
Stainless steel
316
Stainless
steel
316 is readily brake or roll formed into a variety of parts. It is
also suited to stamping, heading and drawing but post work annealing is
recommended to relieve internal stresses.
Cold working will increase both strength and hardness of Stainless
steel
316.
Hot Working of
Stainless steel
316
All common hot working processes can be performed on Stainless
steel
316. Hot working should be avoided below 927°C. The ideal temperature
range for hot working is 1149-1260°C. Post-work annealing is recommended to
ensure optimum corrosion resistance.
Heat Treatment of
Stainless steel
316
Stainless
steel
316 cannot be hardened by heat treatment.
Solution treatment or annealing can be done by rapid cooling
after heating to 1010-1120°C.
Machinability
Stainless
steel
316
has good machinability. Machining can be enhanced using the following
rules:
·
Cutting edges must be kept sharp. Dull edges cause excess work
hardening.
·
Cuts should be light but deep enough to prevent work hardening by
riding on the surface of the material.
·
Chip breakers should be employed to assist in ensuring swarf
remains clear of the work
·
Low thermal conductivity of austenitic alloys results in heat
concentrating at the cutting edges. This means coolants and lubricants are
necessary and must be used in large quantities.
Welding of
Stainless steel
316
Fusion welding performance for 316 stainless
steel is excellent both with
and without fillers. Recommended filler rods and electrodes for Stainless
steel
316 and 316L are the same as the base metal, 316 and 316L
respectively. Heavy welded sections may require post-weld annealing. Grade 316Ti
may be used as an alternative to Stainless
steel
316 in heavy section welds.
Oxyacetylene welding has not been found to be successful for
joining of Stainless
steel
316.
316Ti
Another variation of 316 is available. This variation is
316Ti. Stainless steel
316Ti contains a small amount of titanium. Titanium content is typically
only around 0.5%. The titanium atoms stabilise the structure of the 316 at
temperatures over 800°C. This prevents carbide precipitation from the grain
boundaries and protects the metal from corrosion. The main advantage of 316Ti is
that it can be held at higher temperatures for a longer period without
sensitisation (precipitation) occurring. 316Ti retains physical and mechanical
properties similar to standard grades of 316.
Applications of
Stainless steel
316
Initially developed for use in paper mills Stainless
steel
316 is now typically used in:
·
Food processing equipment
·
Brewery, dairy, and pharmaceutical production equipment
·
Chemical and petrochemical equipment
·
Laboratory benches & equipment
·
Coastal architectural panelling
·
Coastal balustrading
·
Boat fittings
·
Chemical transportation containers
·
Heat exchangers
·
Mining screens
·
Nuts and bolts
·
Springs, nuts, bolts and screws
·
Medical implants
·
Sinks and splashbacks
·
Saucepans
·
Cutlery and flatware
·
Sanitaryware and troughs
·
Tubing
Supplied Forms
Stainless
steel
316 is typically
supplied by Aalco in a range of finishes in the following forms:
·
Sheet
·
Strip
·
Tube
·
Bar
·
Pipe
·
Plate
·
Fittings & Flanges |