Below are the most frequently asked questions about SAF™ 2707 HD hyper-duplex stainless steel.

  • What is a hyper-duplex material?

    It is a duplex stainless steel grade with even better corrosion resistance than the super-duplex grade SAF™ 2507. That is why we call it 'hyper-duplex'. Generally, it behaves as a super-duplex stainless steel, but SAF™ 2707 HD can be used in much more aggressive environments. The nominal PRE value for SAF™ 2707 HD hyper-duplex stainless steel is min. 48 (valid for tube and pipe).

  • What is the chemical composition of SAF™ 2707 HD?

    Chemical composition (nominal), %
    Si Mn P
    Cr Ni Mo Others
    0.030 0.3 1.0 0.035 0.010 27 6.5 4.8 N=0.4
  • What product forms are available?

    Today, we can offer tubular products in SAF™ 2707 HD hyper-duplex stainless steel, with a focus on heat exchanger tubes.

  • Are there any matching welding consumables?

    Yes, welding products have been developed in parallel with the base material. Welding wire Exaton 27.7.5.L for GTAW (TIG) is available from ESAB.

  • Are the stress corrosion cracking properties of SAF™ 2707 HD similar to those of SAF™ 2507?

    Yes, results show that SAF™ 2707 HD is at least on the same high level or better than SAF™ 2507.

  • Can SAF™ 2707 HD be used as an alternative to nickel alloys?

    One of the targets with developing SAF™ 2707 HD hyper-duplex stainless steel has been to produce a duplex grade with performance on a similar level to nickel alloys. However, SAF™ 2707 HD is more attractive economically in terms of material and life cycle costs.

  • What references are available?

    SAF™ 2707 HD hyper-duplex stainless steel has been evaluated over the last couple of years in a variety of industrial heat exchanger applications, for example, refinery overhead condensers and seawater coolers.

  • Are there any papers or lectures available about the material?

    Lectures about SAF™ 2707 HD hyper-duplex stainless steel have been held at the Stainless Steel World Conference and Expo in Houston, USA and the NACE Conference in Nashville (TN), US.
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