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Industrial Optical Diagnostic for on-line Control in Thermal spraying


During the project two main changes in technical program have been incorporated to improve the effective potential exploitation. These changes, included in the revised project at the mid term, consist into:
1) Prototype CCD cameras, suitable for the demanding project specifications to the sensor device, appeared in 99. Therefore they were adopted as basic sensor, replacing the original fast pyrometer. This new approach improves the sensor performance (particles speed and size are measured, besides temperature);
2) In running tests, it has been demonstrated that a on-line process control is meaningless, as no feedback algorithm can correlate in feedback the process variable with the process quality.
Therefore a product control approach has been followed: the diagnostic system will be exploitable as stand-alone device for system validation and calibration purpose as well as a on-off system to enable production.
Due to these changes the following deliverables have been fulfilled:
1) Data base on thermal spray processing;
2) Experimental data base on influence of process parameters on process quality;
3) Prototype of diagnostic system able to measure the particles temperature, velocity and size in thermal spray;
4) Prototype of on-line monitoring system for thermal spray process, adequate for ON-OFF product control;
5) SW for automatic data acquisition, treatment, analysis;
6) Technical requirements and recommendations for process control industrial implementation.
Objectives and comment
Thermal Spraying (TS) is a rapidly growing part of
materials engineering with applications in more than 35
modern industrial areas: mechanics (high- and lowfriction coefficient coatings in dry of lubricated
friction, wear resistant coatings); electrical field
(conducting or insulating coatings, magnetic coatings);
thermal field (thermal barriers, thermal conducting
coatings); chemistry (protective coatings, corrosion
resistant coatings); medicine (coatings for prosthesis
and implants). An actual world market of Thermal Spraying
is about 1 billion ECU, with the previewed annual 15%
increase to the end of decade.
To satisfy constantly restricting demands for process
versatility, efficiency and cost the Project is committed
to update TS with the intelligent system of on-line
control capable to provide an automatic closed-loop
process operation. Proposed R&D activity is to realise
the following development plan:
to transfer the modern powerful diagnostic method of
high-temperature media - laser reflectometry into actual
conditions of TS technologies;
to work out the universal technique for real-time
diagnostics of sprayed material (temperature and density)
and substrate (temperature) for the characteristic TS
processes (Flame Spray, Plasma Spray, Wire Arc Spray,
High Velocity Oxygen Fuelling, High Pressure Spray,
to construct an industrial type equipment (remote
optical sensors, fibre delivery system, data acquisition
and treatment unit, feed-back controller) and required
software to provide real-time monitoring of spray and
substrate in course of TS;
to accomplish industrial validation of the control
system for different TS processes and various coating
materials (metals Ni, Mo, W, alloys Ni-Cr, Ni-Co,
composites Al-Si-Polyamide, Ni-Graphite, ceramics Al203,
TiO2, Chromium Carbide and biomaterials Calcium Carbide
and Hydroxyapatite).
The expected achievements concerning the intended endusers due to Project realisation:
reduced costly, time- and materials- consuming preperformance trials (for 20-50%);
increased products quality (15-20%, anti-corrosion and
refurbish coatings deposited by WAS, abradables and solid
lubricants deposited by HVOF, biomaterials deposited by
diminished product loss due to non-conformity (up to
20% for an advanced spraying enterprise);
reduced losses of powder materials, (in average for 15-
20%; the actual cost is up to 450 ECU/kg for regular
powder and up to 700 ECU/kg for certified powder);
decrease energy and water consumption (7-10%);
ameliorated production environment by diminishing
powder evaporation (15-20%), plasma torch heat exceed
(10-15%), noise due to gas overrun (from 120-130 dB down
to 90 dB), ozone generation (to obey 200-250 kg/m3);
better work conditions for the personnel due to reduced
hand-held operations and staff contacts with hazardous
production atmosphere.
The expected annual benefit of process control
implementation may be estimated as 300-400 kECU for an
average Spraying SME, which leads to a total European
benefit about 45-50 MECU.
In general, the developed and validated control equipment
concerns three large industrial markets: Thermal Coating
Products (250-300 MECU) - a considerable improvement of
products quality are expected and new coating
combinations become possible;
Thermal Spraying Equipment Production (100-lS0 MECU) -
the system of process control is to be integrated into
the updated coating workstations;
Diagnostic Equipment Fabrication (100-150 MECU) - the
achieved innovations shall be transferred into another
diagnostic systems applied for different high-temperature
or plasma technologies.
The Project Co-ordinator and end-users will undertake an
active dissemination policy. The scope of potential
industrial users and targeted groups for dissemination
will be provided in course of the Project via partners
regular consumers and collaborators, sale departments,
contact with correlated projects.
The commercial version of process control equipment will
be available on the market 2 years after the completion
of the Project.

Funding Scheme

CSC - Cost-sharing contracts


Topcoat Srl
Zona Industriale Fraz.
64030 Montefino

Participants (6)

7,Rue De L'avouerie 7
4000 Liege
United Kingdom
Eastern Avenue, Gloucester Plating Works
GL4 3DN Gloucester
Z.i. Du Colombier
12220 Montbazens
Permanova Lasersystem AB
30,Krokslatts Fabriker
431 37 Molndal
86,Calle Gabiria 86 Poligono Ventas
20305 Irun
Université de Perpignan
52,Avenue De Villeneuve
66860 Perpignan