Chemical composition (nominal) %

Subject to agreement, material with extra low Co content can be supplied.

Forms of supply

Seamless tube and pipe

Tube and pipe are normally delivered in the solution annealed and white-pickled condition or in the bright-annealed condition. The size range can be seen from Fig. 1. U-tubes can be delivered on request.

Figure 1. Principal size range for seamless tube and pipe.

Mechanical properties

For tube and pipe with wall thickness 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)

1 MPa = 1 N/mm²
a) R_p0.2 and R_p1.0 corresponds 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.

The hardness (Vickers) is approximately 155
The impact strength (Charpy V) at -60 °C (- 75 °F) is min. 150 J (110 ft-lb)

At high temperatures

Physical properties

Density: 7.9 g/cm³, 0.29 lb/in³

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

1) (x10³)

Corrosion resistance

General corrosion

Sandvik 5R10 has good resistance in:

The risk of general corrosion in sulphuric acid during shut down periods has to be taken into account. Since Sandvik 5R10 is not alloyed with molybdenum, the grade can only tolerate low concentrations at limited temperatures. In naturally aerated sulphuric acid the corrosion rate is below 0.1 mm/year provided the temperature is not higher than 20°C (68^oF) in 5% solution.

Intergranular corrosion

Sandvik 5R10 has a relatively high carbon content. Thus, there is a certain risk of reduced intergranular corrosion resistance if the steel has become sensitised after e.g. improper heat treatment or welding. Sandvik 3R12 has a significantly lower carbon content and is therefore more safe regarding intergranular attack.

Pitting and crevice corrosion

The steel may be sensitive to pitting and crevice corrosion even in solutions of relatively low chloride content. Molybdenum alloyed steels have better resistance and the resistance improves with increasing molybdenum content.

Stress corrosion cracking

Austenitic steel is susceptible to stress corrosion cracking. This may occur at temperatures above about 60°C (140°F) if the steel is subjected to tensile stresses and at the same time comes into contact with certain solutions, particularly those containing chlorides. 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 conditions that lead to both stress corrosion cracking and pitting.

In applications demanding high resistance to stress corrosion cracking we recommend the austenitic-ferritic steel Sandvik SAF 2304.

Gas corrosion

Sandvik 5R10 can be use in

Creep behaviour should also be taken into account when using the steel in the creep range. In flue gases containing sulphur, the corrosion resistance is reduced. In such environments the steel can be used at temperatures up to 600-750°C (1110-1380°F) depending on service conditions.

Factors to consider are whether the atmosphere is oxidising or reducing, i.e. the oxygen content, and whether impurities such as sodium and vanadium are present.

Heat treatment

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

Stress relieving

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

Solution annealing

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

Welding

The weldability of Sandvik 5R10 is good. Suitable welding methods are manual metal-arc welding with covered electrodes and gas-shielded arc welding with the TIG and MIG methods as first choice. Preheating and post-weld heat treatment are not normally necessary.

Since the material has low thermal conductivity and high thermal expansion, welding must be carried out with a low heat input and with welding plans well thought out in advance so that the deformation of the welded joint can be kept under control. If, despite these precautions, it is foreseen that the residual stresses might impair the function of the weldment, we recommend that the entire structure be stress relieved. See under "Heat treatment".

As filler material for gas-shielded arc welding we recommend wire electrodes and rods Sandvik 19.9.L or 19.9.LSi. In manual metal-arc welding covered electrodes Sandvik 19.9.LR or 19.9.LRHD are recommended. If flux cored arc welding is preferred, electrodes Sandvik 19.9.LT or 19.9.LVT should be used. For high-temperature application the wire electrode Sandvik 19.9.Nb, 19.9.NbSi or covered electrode 19.9 NbR should be used. The corresponding flux cored arc welding electrode is 19.9.NbT.

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.

Applications

Sandvik 5R10 is used for a wide range of industrial applications with emphasis on high temperature processes. Typical examples are: heat exchangers, condensers, pipelines, cooling and heating coils in the chemical, petrochemical, fertiliser, pulp and paper and nuclear power industries, as well as in the production of pharmaceuticals, foods and beverages.