Skip to main content

Continous high rate liquid phase epitaxy of textured coated conductors


Objectives and content:

The primary objective of this proposal is to develop a novel process for the continuous high rate production of low cost high critical current coated superconductors on metal and ceramic substrates. The proposed programme addresses longer term scientific and technica1 objectives.

At the end of the project there will be:
1) new scientific knowledge in areas relating to high rate production of coated conductors, and;
2) novel patented technology developed to a prototype level for exploitation by European industry. The technique is based on the recent observation of very high growth rates of ReBCO (eg SmBa2Cu307 a) from a supersaturated flux by liquid phase epitaxy (LPE). The key feature of the new process is a patented method to obtain and maintain a high super saturation of the rare earth elements in solution at the superconductor growth interface. This enables the growth rate to be increased by orders of magnitude over both conventional melt processing and competing solution growth techniques. The method also provides novel 'boundary layer' control of liquid supply to the growing super-conducting layer.

Coated conductor research has three distinct components: (i) the substrate, (ii) the buffer layer and (iii) the superconducting layer. As a consequence a number of research topics have to be studied within this programme.

The new scientific knowledge generated will include improved understanding of: (i) extreme super saturation of the BaCuOflux with multiple rare earth elements, (ii) high rate epitaxial growth of ReBCO, including transient and steady state growth, (iii) novel control of the boundary layer in liquid supply to the substrate, (iv) innovative processes for buffer layer formation, (v) high power dynamic V-I testing for power engineering applications, and (vi) irradiation enhancement and high field measurement of the critical current of coated tapes for application in magnet technology.

The new technology developed will include, (i) novel patented high temperature LPE techniques, including a lower risk design that depends on delivery of the supersaturated liquid via a stationary porous plug and a higher risk design that depends on a rotating mandrel, (ii) development of precision porous ceramic components, (iii) differential atmosphere control of melting equilibria by dynamic partial pressure metering and electrochemical control, (iv) novel substrate materials, and (v) stress control coating.

It is expected that commercial equipment based on the new technology developed will be available within three years of the termination of the project. The equipment will be able to supply European industry with: (1) continuous lengths of "coated conductor" for applications involving magnet technology, also (2) large area "coated ceramic shaped elements" for current lead and fault current limiter applications. BE97-4489

Funding Scheme

CSC - Cost-sharing contracts


University of Cambridge
Pembroke Street
CB2 3QZ Cambridge
United Kingdom

Participants (4)

Atominstitut der Österreichischen Universitäten
1020 Wien
United Kingdom
Capenhurst Technology Park
CH1 6ES Chester
Kullinggade 31
Via R. Cozzi 53
20125 Milano