Alleima® 3R65 for medical applications Tube and pipe, seamless

Standards

• ASTM: TP316L, TP316
• UNS: S31603, S31600
• EN Number: 1.4404, 1.4401
• EN Name: X2CrNiMo17-12-2, X5CrNiMo17-12-2
• W.Nr.: 1.4404, 1.4401
• DIN: X 2 CrNiMo 17 13 2, X 5 CrNiMo 17 12 2
• SS: 2348
• AFNOR: Z 2 CND 17.12, Z 6 CND 17.11
• BS: 316S11

Product standards

• ASTM F899, A213, A269, A312
• ISO 16061
• EN 10216-5
• BS 3605, BS 3606
• DIN 17456, 17458
• NFA 49-117, 49-217
• SS 14 23 48

Chemical composition (nominal)

Applications

Thick wall tubes applications:

Alleima® 3R65 is used in a wide variety of industrial applications. For the medical industry, Alleima® 3R65 is used for medical tools.

Thin wall tubes applications:

Biopsy punches, mammography machine, brooches, suspension for oxygen tank for hospital mobile beds, surgical and dental tools.

Corrosion resistance

General corrosion

Alleima® 3R65 has good resistance to:

• Organic acids at high concentrations and temperatures, with the exception of formic acid and acids with corrosive contaminants
• Inorganic acids, e.g. phosphoric acid, at moderate concentrations and temperatures, and sulfuric acid below 20% at moderate temperatures. The steel can also be used in sulfuric acid of concentrations above 90% at low temperature
• Salt solutions, e.g. sulfates, sulfides and sulfites

Intergranular corrosion

Alleima® 3R65 has a low carbon content and therefore better resistance to intergranular corrosion than other steels of type ASTM 316.

Pitting and crevice corrosion

Resistance of these types of corrosion improves with molybdenum content. Alleima® 3R65 has substantially higher resistance to attack than steels of type ASTM 304.

Stress corrosion cracking

Austenitic steels are susceptible to stress corrosion cracking. Stress corrosion cracking may occur if the steel is simultaneously exposed to the following:

• Tensile stresses
• Certain solutions, particularly those containing chlorides
• Temperatures above 60^oC (140^oF)

Such service conditions should therefore be avoided. Conditions when plants are shut down must also be considered, as the condensates which are then formed can develop a chloride content that leads to both stress corrosion cracking and pitting.

In applications demanding high resistance to stress corrosion cracking, austenitic-ferritic steels, e.g. SAF 2304 or SAF 2205 are recommended.

Gas corrosion

Alleima® 3R65 can be used in

• Air up to 850^oC (1560^oC)
• Steam up to 750^oC (1380^oF)

In flue gases containing sulfur, the corrosion resistance is reduced. In such environments Alleima® 3R65 can be used at temperatures up to 600-750^OC (1110-1380^OF) depending on service conditions. Factors to consider are whether the atmosphere is oxidizing or reducing, i.e. the oxygen content, and whether impurities such as sodium and vanadium are present.

Bending

Annealing after cold bending is not normally necessary, but this point must be decided with regard to the degree of bending and the operating conditions. Heat treatment, if any, should take the form of stress-relieving or solution annealing, see under "Heat treatment".

Hot bending is carried out at 1100-850°C (2010-1560°F) and should be followed by solution annealing.

Forms of supply

Seamless tube and pipe- Finishes and dimensions

Seamless tube and pipe in Alleima® 3R65 are supplied in dimensions up to 260 mm outside diameter in the solution annealed and white-pickled condition or in the bright-annealed condition.

Dimension range for tubes, thin wall

OD : 0.5 - 50.80 mm
Wall thickness : 0.1 - 3 mm
Fine tube tolerances :

• Wall thickness tolerance : +/- 10%
• OD tolerance : +/- 0.75% with a minimum of +/-0.02 mm
• Roughness
  for OD> 5mm Ra (outside) < 0.4 (by polishing)
  for ID>3.2mm Ra (inside)< 0.4 - this possibility depends on wall thickness/diameter ratio
  Specific roughness can be done on request
• Internal cleaning can not be done for inside diameter below 4 mm

All products supplied either in the annealed and cold worked condition to provide mechanical properties as required

Heat treatment

Tubes are delivered in the heat treated condition. If additional heat treatment is needed after further processing the following is recommended.

Stress relieving

850-950°C (1560-1740°F), 10-15 minutes, cooling in air.

Solution annealing

1000-1100°C (1830-2010°F), 5-20 minutes, rapid cooling in air or water.

Mechanical properties

Thin wall tubes

Alleima® 3R65 can be supplied in bright annealed or cold worked condition with R_m 860-1100 MPa

Thick wall tubes

For tube and pipe with wall thicknesses greater than 10 mm (0.4 in.) the proof strength may fall short of the stated values by about 10 MPa (1.4 ksi).

At 20°C (68°F)

Mechanical properties can be set according to your demands.

1 MPa = 1 N/mm²
a) R_p0.2 and R_p1.0 correspond to 0.2% offset and 1.0% offset yield strength, respectively.
b) Based on L₀ = 5.65√S₀ where L₀ is the original gauge length and S₀ the original cross-section area.

Impact strength

Due to its austenitic microstructure, Alleima® 3R65 has very good impact strength both at room temperature and at cryogenic temperatures.

Tests have demonstrated that the steel fulfils the requirements (60 J (44 ft-lb) at -196 ^oC (-320 ^oF)) according to the European standards EN 13445-2 (UFPV-2) and EN 10216-5.

At high temperatures

Physical properties

Density: 8.0 g/cm³ , 0.29 lb/in³

1) Mean values in temperature ranges (x10^-6)

Machining

Alleima® 3R65 has good machining properties. However the machining of Alleima® 3R65, as with other stainless steels, requires an adjustment of tooling data and machining method, in order to achieve satisfactory results. Compared to Sanmac® 316/316L, the cutting speed must be reduced by approximately 30-40 % when turning Alleima® 3R65 with coated, cemented carbide tools. Much the same applies to other operations.

Feeds should only be reduced slightly and with care.

Detailed recommendations for the choice of tools and cutting data are provided in the brochure S-02909-ENG. Data should be selected as for steel grade Sanmac® 316/316L, while taking into account the provisions above.

Welding

The weldability of Alleima® 3R65 is good. Welding must be carried out without preheating and subsequent heat treatment is normally not required. Suitable methods of fusion welding are manual metal-arc welding (MMA/SMAW) and gas-shielded arc welding, with the TIG/GTAW method as first choice.

For Alleima® 3R65, heat input of <2.0 kJ/mm and interpass temperature of <150°C (300°F) are recommended.

Recommended filler metals

TIG/GTAW or MIG/GMAW welding

ISO 14343 S 19 12 3 L / AWS A5.9 ER316L (e.g. Exaton 19.12.3.L)

MMA/SMAW welding

ISO 3581 E 19 12 3 L R / AWS A5.4 E316L-17(e.g. Exaton 19.12.3.LR)