C8.

Project title: Development of a novel temperature history indicator based on phase transformation and nanotechnology

The idea of this project is built on a previous invention by Professor Lai and co-workers called Feroplug, which was patented in USA, UK and Europe by the British Technology Group. The Feroplug is a piece of specially designed duplex stainless steel which undergoes a phase transformation at elevated temperatures. The current idea is new and involves the use of two or more Feroplugs with different transformation kinetics to determine the temperature history of an object which had experienced a simple thermal cycle. The technique can be supplemented with a later development of the Feroplug called Sigmaplug and with Professor Lai and co-workers?recent research results that the grain growth characteristics of nano-particles of tin dioxide can be used to indicate temperature. In the latter case the project lies in the exciting new field of nanotechnology.

Unlike thermocouples, no cables or wires are needed in this new technique, making it particularly suitable for objects that need to be moved. It also does not have the disadvantage of techniques such as pyrometry that the result is affected by the surface emissivity of the object which can vary according to the extent of corrosion upon exposure to high temperature environments, or by the presence of particles in the light path between the object and the radiation detector.

It is expected that this project will contribute to the development of an innovative product with wide applications, particularly in industrial heat treatment furnaces. An international local company with a plant in Hong Kong is interested in this technique with a view to enhancing quality assurance in the heat treatment of metal slabs. Students taking this project may have the opportunity to gain some industrial experience by involving with collaborative plant trial experiments to be carried out at this company.

Supervisor/Associate Supervisors:
Prof Joseph K L Lai (apjoelai@cityu.edu.hk)/
Dr C H Shek (apchshek@cityu.edu.hk)

Suitable for: M.Phil./Ph.D.