What is HELIX
Advancing in the knowledge of hydrogen absorption in high strength steels for energy application
The HELIX project aims to provide lower cost, high corrosion resistant, high strength steel and high diameter fasteners to the offshore wind industry to support the ever-increasing size of wind turbines, leading to higher productivity and supporting the development of larger foundations to support above 10MW OWT, and allow an easy assembly and disassembly of the whole structure.
HELIX will use advanced characterisation and traditional techniques under both atmospheric and immersion conditions to advance in the knowledge of hydrogen absorption in high strength steels under cathodic protection and in atmospheric conditions.
This knowledge will not only allow tailoring the steel and coating microstructure to achieve both excellent corrosion protection ability and low risk of hydrogen embrittlement, but also influence on policy and practice in the offshore wind sector.
HELIX will also identify the mechanisms of hydrogen absorption/desorption of the optimised steels, as well as develop coatings based on zinc flakes and different topcoat materials to protect the steel and to reduce hydrogen entry in service.
Increasing steel application competitiveness
Unlocking the full potential of the offshore turbines
The new European Green Deal plans to accelerate the use of electricity produced from renewables, developing the full potential of Europe’s offshore wind energy.
Offshore wind is set to play a central role and has the potential to become the largest source of electricity supply.
Several types of offshore structures are already used or in development. A great deal of offshore wind projects in Europe are being developed and installed capacity is expected to increase in the next years.
To increase efficiency and lower production costs, the offshore wind industry is focusing on the development of larger wind generators, in which the HELIX project contributes by providing more resistent high-strength steel fasteners.
What is hydrogen embrittlement?
Hydrogen enters into the material via adsorption through the surface. Once absorbed, it is trapped in different microstructural sites with different activation energy.
Hydrogen located in interstitial sites is called “diffusible hydrogen” and presents the lowest activation energy.
When the material is exposed to external stresses or residual stresses, diffusible hydrogen diffuses to zones of high stress, resulting in hydrogen embrittlement.