Austenitic & Super Austenitics Steels
TP 316Ti • UNS S31635 • 1.4571
- Application
316Ti (UNS S31635) is a titanium stabilised version of 316 molybdenum bearing austenitic stainless steel. The 316 alloys are more resistant to general corrosion and pitting/crevice corrosion than the conventional chromium-nickel austenitic stainless steels such as 304. They also offer higher creep, stress-rupture and tensile strength at elevated temperature High carbon Alloy 316 stainless steel can be susceptible to sensitisation, the formation of grain boundary chromium carbides at temperatures between approximately 900 and 1500°F (425 to 815°C) which can result in intergranular corrosion.
Resistance to sensitisation is achieved in Alloy 316Ti with titanium additions to stabilise the structure against chromium carbide precipitation, which is the source of sensitisation. This stabilisation is achieved by an intermediate temperature heat treatment, during which the titanium reacts with carbon to form titanium carbides. This significantly reduces susceptibility to sensitisation in service by limiting the formation of chromium carbides. Thus, the alloy can be used for extended periods at elevated temperatures without compromising its corrosion resistance.
316Ti has equivalent corrosion resistance to sensitisation as the low carbon version 316L.
- Typical manufacturing specifications
ASTM A213
Also individual customer specifications.
- Industries predominantly using this grade
Chemical processes, High temperature Automotive, Oil and Gas etc.
Technical Data
Chemical Composition(% by Weight)
Element | C | Mn | P | S | Si | Ni | Cr | Mo | N | Ti |
|---|---|---|---|---|---|---|---|---|---|---|
Minimum | - | - | - | - | - | 10.0 | 16.0 | 2.00 | - | 5*(C+N) |
Maximum | 0.080 | 2.00 | 0.045 | 0.030 | 0.75 | 14.0 | 18.0 | 3.00 | 0.10 | 0.70 |
Aiming | 0.03 | 1.5 | 0.03 | 0.002 | 0.5 | 10.5 | 16.6 | 2.0 | - | 0.3 |
Mechanical Properties
| Specifications(Tubing, Annealed) | Actual data | |||
|---|---|---|---|---|
|
Tensile Rm |
75 |
ksi (min.) |
79 ~ 98 |
ksi |
|
Tensile Rm |
515 |
MPa (min.) |
550 ~ 680 |
MPa |
|
Yield (R.p. 0.2%) |
30 |
ksi (min.) |
35 ~ 56 |
ksi |
|
Yield (R.p. 0.2%) |
205 |
MPa (min.) |
250 ~ 370 |
MPa |
|
Elongation |
35 |
% (min.) |
45 ~ 52 |
% |