FAQ 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?

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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