Wed, 04 January, 2023
Working as part of the GEOHEX project, TWI has developed a new functional electroless nickel-phosphorous plating (ENP) composite coating for use in the demanding environments associated with geothermal energy.
ENP coatings are used in industries ranging from aerospace and construction to electronics, and oil and gas. These coatings are favoured for their exceptional tribological and mechanical properties including high hardness, antifouling, anti-scaling, and good resistance to wear and corrosion, making them suitable for geothermal applications too.
Controlling the microstructure of ENP coatings allow these properties to be fine-tuned, tailoring the alloy chemistry, post-plating heat treatments and more to enhance specific functionalities as required. The incorporation of nanoparticles into the coatings can further enhance these functionalities to improve hydrophobicity, coefficients of friction, and more.
The developments afforded by the work of TWI allows for the creation of coatings with specific properties according to requirements of the final application, whether antifouling, resistance to corrosion and wear or hydrophobicity is required (see figures below).
Figure 1. Representative images of ENP-PTFE composite coating. (left) A back scattered electron (BSE) image of the cross-section of the duplex coating on a steel substrate (1: steel substrate; 2: Ni-P undercoat; 3: Ni-P-PTFE topcoat); dark features in the topcoat correspond to PTFE functional nanoparticles. (right) High resolution BSE image of the Ni-P matrix with embedded PTFE nanoparticles.
Figure 2. Static water contact angle measurement on Ni-P-PTFE composite coating demonstrating its hydrophobic nature.
The GEOHEX project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 851917