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Coating and Surface Protection

Coatings are a layer that can be used to cover the surface of the substrate. In our daily life several products are coated for one reason or another. Several practices and process have been used to apply and maintain this layer. At IR4TD we are studying the science behind the application and inspection of several types of coatings. Such knowledge can lead to better coating application and surface finish, lower material waste, lower energy consumption, lower environmental impact, and better training tools.

At IR4TD we have the expertise in:

A spray is generally considered as a system of droplets immersed in a gaseous continuous phase. There are many occurrences of spray phenomena in power and propulsion applications, industrial applications, and nature.  Sprays are produced as a result of atomization, which is defined as the disintegration of liquid into dropletsAtomization of a liquid into discrete droplets can be brought about by the use of diverse mechanism like aerodynamic, mechanical, ultrasonic, or electrostatic forces. For example, the breakup of a liquid into droplets can be achieved by the impingement with a gas in two-fluid atomization, by centrifugal forces in rotary atomization, by ultrasonic vibration utilizing a piezoelectric transducer in ultrasonic atomization, or by electrostatic/electromagnetic fields in electrostatic/electromagnetic atomization.

When a liquid is sprayed, it forms ligaments due to the interaction of the surface tension and the air resistance. The surface tension breaks the liquid jet into individual droplets that are capable of holding themselves together at their velocities. Very large droplets once formed will split further if the surrounding ambient resistance overcomes the surface tension. In the vast majority of industrial processes air assisted atomizers are used, where compressed air supplies the required energy for atomizing the liquid.

IR4TD has expertise in all forms of spray atomization and application.

When paint is applied to any substrate, it is necessary to functionalize or cure it by the addition of heat or energy. This energy is typically added by infrared radiation or convection ovens. For automotive assembly plants, paint curing consumes 20% of the total plant energy, making it the second highest energy consumption operation after the paint booths. This high energy consumption is due, in part, to process inefficiencies and a lack of understanding of paint materials and their chemistry. At the IR4TD, we study curing to:

  • Lower the energy consumption
  • Lower the environmental impact of the process

This research targets:

  • Novel, selective heating regimes such as radio frequency, microwave and ultraviolet radiation
  • Novel additives to enhance absorption of energy in selective spectral ranges
  • Energy analysis and process optimization
  • Mitigation of volatile organic compounds (VOC's) and greenhouse gases

Paint is used to protect, beautify, or provide a texture to a specimen or product surface. It is common practice to apply multiple paint layers to achieve an attractive finish. Surface preparation, paint application and then curing of paints are used to assure proper coverage and functionalization of the paint. The presence of defects in painted layers will reduce or degrade its appearance and perhaps its integrity. 

It is very difficult to eliminate paint defects due to the complexity of paint processes. These defects can be traced back to process, chemistry or object related issues. Hence, defect detection and inspection procedures and systems are essential to produce defect-free products. Although these procedures have been based mainly on visual examinations, the use of automated systems would increase dramatically process efficiencies and productivities.  The IR4TD is examining such automated systems that will:

  • Provide statistical information for defects and points of origin
  • Reduce decision time in case of repeated defects
  • Identify preventive maintenance schedules depending on defect’s severity

These systems target research and development to:

  • Develop novel remote detection systems for both surface and subsurface defects
  • Develop novel image processing techniques
  • Develop data storage and data mining techniques

During the painting of automobiles, machinery and consumer products, up to 50% of the paint sprayed toward a surface does not coat it; rather, it becomes overspray in the air that cannot be exhausted to the plant atmosphere because of its environmental characteristics. To efficiently capture this overspray, the IR4TD created a truly innovative and unique technology called “Vortecone”. In comparison to other overspray capture technologies, Vortecone saves 30-55% on energy consumption, has capture efficiencies as high as 99.996%, can actually decrease the relative humidity of the air exiting the system as compared to that entering, uses 30-50% less water during operation, and almost eliminates the need for any cleaning of the capture system.

Vortecone is an example of IR4TD"s computational and engineering design ingenuity. Ongoing research aims to further improve it.


For more information please contact us