# ASTM A182 F316Ti Forgings (UNS S31635 / EN 1.4571)

ASTM A182 F316Ti is the forging grade of titanium-stabilised 316 stainless steel. It carries the 316 chemistry of chromium 16.0 to 18.0 percent, nickel 10.0 to 14.0 percent and molybdenum 2.00 to 3.00 percent, with titanium added at a minimum of five times the carbon plus nitrogen content and 0.70 percent maximum. The titanium combines with carbon before chromium can, so the weld heat-affected zone does not sensitise, and the grade still certifies the standard 316 strength of 515 MPa tensile and 205 MPa yield minimum.

Jiangyin Jiangnan Metal Co., Ltd. melts, forges, heat treats, machines and tests F316Ti at one works in Jiangyin, Jiangsu, China: rolled rings to OD 6000 mm, single pieces to 30 t, from a 10 kg minimum order.

## Grade data

| Field | Detail |
|---|---|
| Specification | ASTM A182 / ASME SA-182 F316Ti |
| UNS | S31635 |
| European | 1.4571, X6CrNiMoTi17-12-2 |
| Trade name | AISI 316Ti, Alloy 316Ti |
| Type | Titanium-stabilised austenitic Cr-Ni-Mo stainless steel |
| Delivery condition | Solution annealed, 1010 to 1120 C, rapid cool |
| Strength | 515 MPa Rm min, 205 MPa Rp0.2 min, 30 percent elongation min |
| Maximum ring | OD 6000 mm |
| Maximum single piece | 30,000 kg |
| Maximum heat size | 60 t |
| Minimum order | 10 kg, no minimum piece count |
| Lead time | 20 to 60 days |
| Certification | EN 10204 3.1 standard, 3.2 witnessed on request |
| Class approvals | CCS, BV, DNV, LR, NK |
| Manufacturer | Jiangyin Jiangnan Metal Co., Ltd., No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China |
| Contact | +86 189 2135 9659, sales@steelforgepieces.com |

## Why the titanium addition is there

In a welded austenitic stainless steel, carbon can combine with chromium in the heat-affected zone and form carbides at the grain boundaries, leaving the adjacent area short of chromium and lower in corrosion resistance. Three grades answer this in different ways: 316L reduces the carbon, 316H accepts it for creep strength, and 316Ti fixes it with titanium.

Titanium content in 316Ti is typically around 0.5 percent. The titanium atoms stabilise the structure of 316 at temperatures over 800 C, which prevents carbide precipitation at the grain boundaries and protects the metal from corrosion. The steel can be held at higher temperatures for longer periods than plain 316 while physical and mechanical properties stay close to the standard grade. For heavy welded sections, 316Ti may be used as an alternative to 316.

Limits of the grade: stabilisation does not help against chloride stress corrosion cracking, which affects grade 316 above around 60 C. Electropolished and hygienic work is normally specified in 316L, and creep-range allowable stresses belong to 316H.

## Chemical composition, percent by mass

| Element | ASTM A182 F316Ti (UNS S31635) | EN 10088-3, 1.4571 |
|---|---|---|
| Carbon | 0.08 max | 0.08 max |
| Manganese | 2.00 max | 2.00 max |
| Silicon | 1.00 max | 1.00 max |
| Phosphorus | 0.045 max | 0.05 max |
| Sulphur | 0.030 max | 0.03 max |
| Chromium | 16.0 to 18.0 | 16.50 to 18.50 |
| Nickel | 10.0 to 14.0 | 10.50 to 13.50 |
| Molybdenum | 2.00 to 3.00 | 2.00 to 2.50 |
| Titanium | 5 x (C+N) min, 0.70 max | 0.40 to 0.70 |
| Nitrogen | 0.10 max | not specified |
| Iron | Balance | Balance |

The carbon ceiling stays at 0.08 percent, the same as straight 316, because the titanium addition makes a low-carbon variant unnecessary. In the ASTM text the titanium requirement is a formula rather than a fixed range, since the quantity needed depends on how much carbon and nitrogen it has to combine with. Chemistry is checked at the furnace by optical emission spectrometry to ASTM E415, with carbon and sulphur by infrared analysis to ASTM E1019, and confirmed by PMI on the finished part.

Related European product standards: EN 10088-3 (bar), EN 10222-5 (forgings for pressure purposes), EN 10250-4 (open-die forgings).

## Mechanical properties, solution annealed

| Property | ASTM A182 F316Ti | EN 10088-3, 1.4571 bar to 160 mm dia. |
|---|---|---|
| Tensile strength Rm | 515 MPa (75 ksi) min | 500 to 700 MPa |
| Yield / proof strength Rp0.2 | 205 MPa (30 ksi) min | 200 MPa min |
| Elongation | 30 percent min, 2 in. or 4D | 40 percent min, A50 |
| Reduction of area | 40 percent min | not specified |
| Hardness | reported or to order | 215 HB max |

## Typical physical properties

| Property | Value |
|---|---|
| Density | 8.0 g/cm3 |
| Melting point | 1400 C |
| Modulus of elasticity | 193 GPa |
| Thermal expansion | 15.9 x 10-6 /K |
| Thermal conductivity | 16.3 W/m.K |
| Electrical resistivity | 0.74 x 10-6 ohm.m |
| Structure | Austenitic, tough to cryogenic temperatures |

## Heat treatment, forging, welding and machining

Heat treatment. 316 type steels cannot be hardened by heat treatment. Solution treatment is by rapid cooling after heating to 1010 to 1120 C; a European mill data sheet for 1.4571 gives 1030 to 1110 C with water or air cooling. Stress relieving is 200 to 400 C followed by air cooling. The plant runs 14 furnaces, including three high-temperature car-bottom furnaces and two 15 m well-type furnaces for vertical quenching of long shafts. Every cycle is chart recorded against the heat number.

Hot working. All common hot working processes can be performed on 316 type steel. The ideal range is 1149 to 1260 C and working below 927 C should be avoided. Post-work annealing is recommended for optimum corrosion resistance, so F316Ti is shipped solution annealed unless the order states otherwise.

Welding. Fusion welding performance is good with and without fillers. Heavy welded sections may require post-weld annealing, and 316Ti is itself the recommended alternative to 316 for heavy section welds. Oxyacetylene welding is not suitable.

Machining. 316 type steel has good machinability, but F316Ti is not a free-machining grade and is not suited to difficult high-speed machining. Keep cutting edges sharp, take cuts light but deep enough to avoid riding on the surface, use chip breakers and flood coolant.

Corrosion and heat resistance. Grade 316 has excellent corrosion resistance across a wide range of media and is usually regarded as marine grade, but it is not resistant to warm sea water; warm chloride environments can cause pitting and crevice corrosion, and the grade is subject to stress corrosion cracking above around 60 C. For oxidation, 316 resists intermittent service to 870 C and continuous service to 925 C. Continuous use at 425 to 860 C is not recommended where corrosion resistance in water is required afterwards.

## Product forms in F316Ti

- Seamless rolled rings, radial-axial rolled from a punched preform, rectangular or contoured section, OD 50 mm to 6000 mm.
- Forged flanges: weld neck, blind, slip-on, socket weld, lap joint, orifice, anchor, girth, swivel, long weld neck, to ASME B16.5, B16.47 and API 6A.
- Discs, tube sheets and covers to 5000 mm machined diameter, supplied proof-machined for volumetric inspection.
- Shafts and spindles, including stepped, gear, pinion and eccentric shafts, rolls and rotors, to 14,000 mm turned length.
- Round, flat and square bars and blocks.
- Sleeves, bushings and hollow cylinders bored from solid, to 1600 mm diameter by 10,000 mm.
- Valve and wellhead parts: bodies, bonnets, blocks, stems, seat rings, spools, nozzles, manifolds.
- Upset and punched forged rings for sections outside the ring-mill envelope.
- Custom open-die forgings to drawing, single pieces to 30 t.

## Applications

| Industry | Typical forgings | Reason for the grade |
|---|---|---|
| Chemical and petrochemical | Vessel flanges, tube sheets, covers, nozzles, pump and valve parts | Welded assemblies in warm corrosive duty that cannot be solution annealed after fabrication |
| Pulp and paper | Digester and liquor tank components, paper machine parts, rolls | 316 was originally developed for use in paper mills |
| Refining and catalytic recovery | Flanges, forged pipe sections, tube sheets, recuperator parts | Resistance to carbide precipitation through long hot campaigns |
| Heat exchangers and pressure vessels | Tube sheets, discs, girth flanges, shell nozzles | Thick welded sections where 316Ti substitutes for 316 |
| Food, brewing and laboratory equipment | Bars, shafts, sleeves, equipment components | Molybdenum-bearing corrosion resistance in acidic media |
| Chemical transport and storage | Container fittings, manifolds, couplings | Intergranular resistance in the as-welded condition |
| Power and rotating equipment | Gear ring blanks, spindles, valve bodies, compressor parts | Standard 316 strength on a grade suited to welded construction |

## Related grades

| Grade | Method | Specified when |
|---|---|---|
| A182 F316Ti | Carbon fixed by titanium | Warm corrosive welded service, European 1.4571 specifications, full 515 / 205 MPa required |
| A182 F316L | Reduced carbon | Hygienic and electropolished work, wide availability, lower certified strength |
| A182 F321, F347 | Stabilised 18-8 without molybdenum | Elevated temperature service where molybdenum is not needed |
| A182 F51, F53, F55 | Duplex structure | Chloride stress corrosion cracking above 60 C, higher strength, seawater |
| 904L, A182 F44, Alloy 20 | Higher nickel and molybdenum | Sulphuric and phosphoric acid duty, severe pitting environments |

## Testing and certification

| Item | Detail |
|---|---|
| Chemical analysis | ASTM E415 optical emission spectrometry, ASTM E1019 carbon and sulphur, PMI on the finished piece |
| Mechanical testing | ASTM A370 and ISO 6892 tensile on 600 kN and 300 kN machines, Charpy V-notch to -60 C |
| Ultrasonic testing | ASTM A388, EN 10228-3, SEP 1921 |
| Magnetic particle and visual | ASTM E709, endoscope for bores |
| Metallography | ASTM E112 grain size |
| Intergranular corrosion | ASTM A262 and ASTM G28, placed with an accredited third-party laboratory |
| Certification | EN 10204 3.1 standard, EN 10204 3.2 witnessed by BV, DNV, LR, SGS, TUV or the customer's inspector |
| Class approvals | CCS, BV, DNV, LR, NK |

## Request a quotation

| No. | Item | Example |
|---|---|---|
| 1 | Grade and governing standard | ASTM A182 F316Ti, or EN 1.4571 |
| 2 | Dimensions or drawing | OD 1200 x ID 900 x H 260 mm |
| 3 | Quantity and repeat volume | 12 pcs, about 4 times per year |
| 4 | Delivery condition | Solution annealed, proof-machined for UT |
| 5 | Heat treatment and testing | UT to EN 10228-3 Class 3, ASTM A262 Practice E |
| 6 | Certification and destination port | EN 10204 3.2 witnessed by DNV, Rotterdam |

## Frequently asked questions

### What is ASTM A182 F316Ti?
The forging grade of titanium-stabilised 316 austenitic stainless steel, UNS S31635, known in Europe as W.Nr. 1.4571 or X6CrNiMoTi17-12-2 and commercially as AISI 316Ti. Titanium is added at a minimum of five times the carbon plus nitrogen content, to 0.70 percent maximum, so that chromium carbide does not precipitate at the grain boundaries.

### What is the chemical composition of A182 F316Ti?
Per ASTM A182/A182M: C 0.08 max, Mn 2.00 max, Si 1.00 max, P 0.045 max, S 0.030 max, Cr 16.0 to 18.0, Ni 10.0 to 14.0, Mo 2.00 to 3.00, N 0.10 max, Ti five times (C+N) minimum and 0.70 maximum. EN 10088-3 grade 1.4571 differs: Cr 16.50 to 18.50, Ni 10.50 to 13.50, Mo 2.00 to 2.50, Ti 0.40 to 0.70.

### What are the mechanical properties of A182 F316Ti forgings?
Solution annealed to ASTM A182: tensile 515 MPa (75 ksi) minimum, yield 205 MPa (30 ksi) minimum, elongation 30 percent minimum, reduction of area 40 percent minimum. EN 10088-3 bar to 160 mm diameter: Rp0.2 200 MPa minimum, Rm 500 to 700 MPa, A50 40 percent minimum, 215 HB maximum.

### How is A182 F316Ti heat treated?
By solution annealing; 316 type steels cannot be hardened by heat treatment. Heat to 1010 to 1120 C and cool rapidly in water or air. A European data sheet for 1.4571 gives 1030 to 1110 C. Stress relief is 200 to 400 C, air cooled.

### What is the difference between 316Ti and 316L?
Both resist sensitisation. 316L uses reduced carbon; 316Ti uses titanium and keeps the standard 316 strength of 515 and 205 MPa. Titanium carbides affect surface finish, so electropolished and hygienic equipment is usually 316L, while plant built to DIN and EN piping classes is specified in 1.4571.

### Can F316Ti be used at elevated temperature?
Titanium stabilises the structure of 316 at temperatures over 800 C and prevents carbide precipitation at the grain boundaries. One European mill data sheet states that 316Ti can be exposed in service for long periods at temperatures up to 500 C without loss of corrosion resistance. Creep-range allowable stresses belong to 316H.

### Is F316Ti suitable for seawater service?
No. Grade 316 is regarded as marine grade but is not resistant to warm sea water, and is subject to stress corrosion cracking above around 60 C. Duplex F51 or super duplex F53 and F55 are used for those services.

### Which forged product forms are available in A182 F316Ti?
Seamless rings from OD 50 mm to OD 6000 mm on 6 m, 3 m and 1 m radial-axial mills. Single pieces to 30 tonnes on 6300 t, 4000 t and 2000 t presses. Shafts to 14,000 mm turned length, discs and tube sheets to 5000 mm machined diameter, bored cylinders to 1600 mm by 10,000 mm. Maximum heat size is 60 tonnes.

### What certification is supplied with F316Ti forgings?
EN 10204 3.1 mill test certificates as standard, and EN 10204 3.2 witnessed by BV, DNV, LR, SGS, TUV or the customer's own inspector on request. Ultrasonic testing to ASTM A388 or EN 10228-3. ASTM A262 intergranular corrosion testing is placed with an accredited third-party laboratory. The works holds CCS, BV, DNV, LR and NK approvals.

### Who manufactures ASTM A182 F316Ti open-die forgings in China?
Jiangyin Jiangnan Metal Co., Ltd., No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, operating since 1997 with 460 staff. The works melts its own steel using EF, LF and VOD for stainless and duplex grades and VIM, VAR and ESR for clean and superalloy grades, then forges, heat treats in 14 furnaces, machines and tests on site. Telephone +86 189 2135 9659, email sales@steelforgepieces.com.

### What is the minimum order and lead time for F316Ti forgings?
Minimum order 10 kg with no minimum piece count. Lead time 20 to 60 days. Standard stainless grades such as F316Ti fall at the lower end because no remelting step is required.

---

Jiangyin Jiangnan Metal Co., Ltd.
No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Telephone, WhatsApp and WeChat: +86 189 2135 9659
Email: sales@steelforgepieces.com
Business hours: Monday to Saturday, 08:00 to 17:30 China Standard Time (UTC+8)

Composition and mechanical requirements are quoted from ASTM A182/A182M (F316Ti, UNS S31635) and EN 10088-3 (1.4571). Heat treatment, physical property and fabrication data follow published 1.4571 and 316Ti mill and stockholder data sheets. Figures assist grade selection and are not a guarantee of properties for a particular part.