The high temperatures (> 400øC) of many industrial processes within the petrochemical, electricity generating and other sectors are well known to cause embrittlement and cracking of metal surfaces. The primary mechanism is the diffusion of impurities such as carbonitrides and alternative metallic solid phases towards grain boundaries in the metal structure. Failure to receive prior warning of materials failure in this manner results in several days of plant downtime which can cost over 75 kECU per day within the petrochemical industry. Current methods of grain boundary analysis, including metallography and electron spectroscopy techniques, are laboratory based and involve the removal of samples., which in itself requires downtime. There are no existing techniques available which can operate on-line. Laser induced breakdown spectroscopy (LIBS) involves vaporisation by a pulsed laser of a mg amount of surface material to create an energised plasma. Emission spectra from this plasma can be analysed to detect the presence of most elements, and LIBS has been developed for a number of analytical applications within the nuclear and steel industries, and also for analysis of soils and geological samples. This project will develop LIBS as an on-!ine technique for the mapping of elemental composition in the region of grain boundaries at heat affected zones. Several problems are presented; - Satisfactory spatial resolution must be achieved. Ideally a resolution at sub-micron level is necessary, but there are limits to the minimum achievable laser spot size. Lateral approaches will be used to obtain a useful 2D resolution -The spectrometer will be subject to a strong thermal radiation flux from the exposed hot sample surface. Ruggedisation will be required in order to protect the components of the spectrometer. - Interpretation of results is a complex procedure, particularly as chemical composition must be deduced from elemental composition at a particular point. Advanced data processing and intelligence features will be developed in order to aid interpretation of the spectra and decrease the skill level required for operation to that of non-expert users. The project will involve; initial specifications; laboratory experiments; development of control/alignment systems; signal processing and intelligence features; design, development and construction of prototypes; and an end-of-project testing programme. The consortium assembled for this project include two SMEs who will be involved in design and development of the prototype spectrometer, a laser system sales company with knowledge of end user requirements, a research institute with specific expertise in LIBS, a research institute with expertise in data processing and intelligence, and a large end user within the petrochemical industry. Use of the spectrometer by end users in the petrochemical, electricity and other industries will have significant benefits, particularly in terms of reduced downtime. It is estimated that the total economic impact of the project on the EU economy in the five years after market introduction will be in excess of 455 MECU.
Funding SchemeCSC - Cost-sharing contracts
12489 13.9 Berlin
SO45 6YY Hythe - Southampton
SO41 8AL Lymington