Background The automotive industry relies on a wide range of materials, ranging from polypropylene body parts to multilayer alloy coatings on engine components, to meet stringent consumer and legal requirements.
Driving Forces for New Materials in the Automotive IndustryEnvironmental legislation on VOCs, chlorinated solvents and low-toxicity processes coupled with improved impact safety standards has led to the introduction of many new materials. In addition consumer demands have necessitated new methods of achieving superb cosmetic appearance and toughness with near zero reject rates.
Analytical Techniques used to Investigate Materials-Related Automotive ProblemsX-Ray Photoelectron Spectroscopy (XPS), Imaging Time-of-Flight Secondary Ion Mass Spectrometry (ToFSIMS) and 3DP-a surface topography technique have been used to investigate problem in areas such as Lubrication, Wear, Paint defects and Electrical component failure.
Where Surface Analysis Has Assisted Auto ManufacturersExamples of investigations:
· Coating conformation and integrity determination
· Contamination analysis and quantification
· Improved production processes
· Component failure analysis
· 'Trouble shooting'
· Product development
Cratering Problems in Paint FilmsRecent advances in extremely high gloss paint finishes has placed exceptionally stringent cleanliness specifications during the robotic painting process. A de-wetted area or a sub-micron sized contamination particulate embedded in the gloss coat mirror finish can reflect a bright spot of light under suitable illumination conditions producing an unacceptable cosmetic appearance.
In this case study, the formation of craters in an automotive coating has been investigated by ToFSIMS.
Mass spectral data, acquired from an area within the crater, provides evidence of PTFE (polytetrafluoroethylene) as the cause of localised de-wetting which results in crater formation during paint application.
ToFSIMS imaging clearly shows the presence and position of PTFE in the de-wetted area (cyan). Organic species from the paint layer are shown in red.
Identification of the contaminant allowed its origin in the manufacturing line to be traced and remedial action taken to prevent recurrence.
Examples of Work Undertaken by CSMA in the Automotive Industry Examples of work undertaken by CSMA in the automotive industry include:
· Analysis of Wax Vapours by GCMS
· XPS Analysis of Ceramic Fabric
· Analysis of Four Bearing Samples
· Investigation of Top-Coat Preparation to Assess Potential for Silicone Contamination
· ToF-SIMS Investigation into the Cause of the Haziness within an Acrylic Laminate Screen.
· XPS Studies into the Variable Adhesion of Metal Shims to Painted back Plates of Brake Pads
· An Investigation of Poor Paint Adhesion on Moulded Car parts
· An XPS and ToF-SIMS Study of Seal Disbondment in Rear Quarterlight Windows for Automobiles.