316Ti stainless steel is an Austenitic grade containing a small amount of titanium element based on 316 alloy, titanium content is typically around 0.5%, and adding the titanium can stabilize the structure of the 316 at temperatures over 800°C. it prevents carbide precipitation at 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 sensitization (precipitation) occurring.
316Ti stainless steel is a derivate of 316 stainless steel and retains physical and mechanical properties similar to standard grades of 316.
316Ti Stainless Steel Composition
The chemical composition of stainless steel 316H is generally composed of 16 to 18% chromium, 10 to 14% nickel, and 2 to 3% molybdenum, and the minimum amount of titanium is 5 x (C + N), the maximum amount is 0.70%, titanium is strong carbide and nitride former, which helps prevent chromium from being consumed.
| C | Mn | P | S | Si | Ni | Cr | Mo | Ti | N | Fe | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 316Ti | 0.08 | 2.00 | 0.045 | 0.030 | 1.0 | 10-14 | 16-18 | 2-3 | 5x(C+N)-0.7 | 0.1 | Balance |
316Ti Stainless Steel Mechanical Properties
| Tensile Strength(Mpa) | Yield Point(Mpa) | Elongation(%) | Hardness, HRB | |
|---|---|---|---|---|
| 316Ti | 515 | 205 | 35 | 86 |
316Ti Stainless Steel Equivalent Grades
| AISI | UNS | DIN | EN | JIS | GB |
|---|---|---|---|---|---|
| 316Ti | S31635 | 1.4571 | X6CrNiMoTi17-12-2 | SUS316Ti | 1Cr18Ni12Mo2Ti |
316Ti Stainless Steel Physical Properties (Room Temperature)
| Density | Melting Point | Specific Heat | Thermal Conductivity | Coefficient Of Expansion | Electrical Resistivity | Elastic Modulus |
|---|---|---|---|---|---|---|
| G/Cm3 | （℃） | [J/(Kg·K)] 0~100 ℃ | [W/(M·K)] 100 ℃ | （10 – 6/K） 0~100 ℃ | NΩ.M | KN/Mm2 |
| 7.99 | 1398~1427 | 500 | 16.3 | 16.6 | 720 | 193 |
Corrosion Resistance
316Ti stainless steel has excellent corrosion resistance due to Titanium and Molybdenum element addition, It can withstand many organic and diluted mineral acids depending on the temperature and concentration of the solution. 316Ti may suffer from uniform corrosion in strong mineral acids, like hot concentrated nitric acid, or hot strong alkaline solutions.
Due to its titanium content, the risk of sensitization for intergranular corrosion is strongly reduced when compared to other austenitic chromium-nickel standards grades with normal carbon content.
316Ti is prone to chloride-induced stress corrosion (SCC) cracking at temperatures over about 50 °C depending on the applied stress and the chloride concentration in the environment. Prior cold deformation of the structure under load increases the risk of stress corrosion cracking.
Heat Treatment
316Ti stainless is a single-phase austenitic (face-centered cubic) stainless steel at all temperatures up to the melting point. Solution treatment or annealing can be done by rapid cooling after heating to 1900- 2150°F (1040-1175°C).
The alloy can not be hardened by heat treatment. The alloy is nonmagnetic in the annealed condition.
Oxidation Resistance
316Ti alloy exhibits excellent resistance to oxidation and a low rate of scaling in air atmospheres at temperatures up to 1600-1650°F (870-900°C). The performance of ATI 316Ti stainless is slightly inferior to that of Type 304 stainless steel, which has higher chromium content (18% vs. 16% for Type 316Ti).
Like other molybdenum-bearing alloys, 316T stainless is subject to catastrophic oxidation at high temperatures in stagnant air atmospheres.
Welding
316Ti has excellent weldability as other austenitic stainless steel grades and is suitable for the full range of conventional welding methods (like MMA, MIG, MAG, TIG, SAW, LBW, or RSW), except gas welding.
316Ti stainless steel often is welded autogenously. If filler metal must be used for welding Type 316Ti, it is advisable to utilize the low carbon Types 316L or E318 filler metals. Contamination of the weld region with copper or zinc should be avoided since these elements can form low melting point compounds, which in turn can create weld cracking.
To fully restore the corrosion resistance of the weld seam, the weld discoloration should be removed by pickling and passivation.
Typical Applications
- Screening application in marine environment
- Pulp and Paper Equipment
- Heat exchangers
- Propeller shafts, Fittings
- Exterior Architectural Components in Marine Coastal Areas
Disadvantages of 316Ti Stainless Steel
While 316Ti stainless steel has many advantages, it also has its drawbacks. One of the main disadvantages is its cost. Due to its high titanium and molybdenum content, this type of steel can be much more expensive than other types of steel.
Another potential drawback is that 316Ti stainless steel may not be suitable for use in certain environments or applications. For example, it may not hold up well when exposed to extremely high temperatures or corrosive chemicals.
In addition, because 316Ti stainless steel contains more alloying elements than other types of stainless steel, it is more difficult to machine and weld. For projects involving this material, this can result in additional labor costs and longer lead times.
Although 316Ti stainless steel is highly resistant to corrosion and contamination, it is still susceptible to rust if not properly maintained. Regular cleaning and maintenance are essential to prevent surface rust.
Despite these drawbacks, many industries continue to choose 316Ti stainless steel because it offers greater strength and durability than other materials on the market today.
316Ti, 316, 316L And 316H Comparison
316 is the basic grade of this group, 316L has a low carbon content of 316, dual certified 316/316L is required for actual uses, 316H carbon element range from 0.04 to 0.1%, 316Ti stainless steel is grade to add titanium based on 316 stainless steel.
| Carbon – Max | N | Titanium | Tensile Strength, Min, Mpa | Yield Strength, Min, Mpa | |
|---|---|---|---|---|---|
| 316 | 0.080 | 0.1 | – | 515 | 205 |
| 316H | 0.04 – 0.10 | – | – | 515 | 205 |
| 316L | 0.030 | 0.1 | – | 485 | 170 |
| 316Ti | 0.08 | 0.1 | 5 X (C + N) Min, 0.70 Max | 515 | 205 |
But 316Ti is not as common as 316 and 316L stainless steel use, although with a higher carbon content, 316Ti has no advantage on mechanical properties, in many cases, 316/316L dual certification is the possible alternative grade of 316Ti.
316Ti stainless steel resist temperatures around 600-900°C, high temperature service (above 1000° F), but compared to 316H, there is no advantage in using 316Ti for high temperature.
316Ti, 1.4571 Comparison
| Standard | Grade | C | Mn | Cr | Ni | Mo | N | Other |
|---|---|---|---|---|---|---|---|---|
| ASTM A240 | 316Ti | ≤0.08 | ≤2.00 | 16.0-18.0 | 10.0-14.0 | 2.00-3.00 | ≤0.10 | Ti 5x (C+N) – 0.70 |
| EN 10088-2 | 1.4571 | ≤0.08 | ≤2.0 | 16.5-18.5 | 10.5-13.5 | 2.0-2.5 | Mo 2.00 – 2.50 Ti 5 X C – 0.70 |
316Ti Stainless Steel Forms
Related References
- ASTM A240/ASME SB240, Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
- ASTM A480, Standard Specification for General Requirements for Flat-Rolled Stainless and Heat-Resisting Steel Plate, Sheet, and Strip
- EN 10088-2, Stainless steels. Technical delivery conditions for sheet/plate and strip of corrosion-resisting steels for general purposes
- EN 10088-3, Stainless steels. Technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products of corrosion-resisting steels for general purposes
- EN 10088-4, Stainless steels. Technical delivery conditions for sheet/plate and strip of corrosion-resisting steels for construction purposes
- EN 10088-5, Stainless steels. Technical delivery conditions for bars, rods, wire, sections and bright products of corrosion-resisting steels for construction purposes
- ASTM A249, Standard Specification for Welded Austenitic Steel Boiler, Superheater, Heat-Exchanger, and Condenser Tubes
- ASTM A213, Standard Specification for Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes
- ASTM A312, Standard Specification for Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes
- ASTM A276, Standard Specification for Stainless Steel Bars and Shape