Session Details
Session 11: Corrosion & Wear Deposit Coatings
Abstract Number:
100
XRF Technology has improved in recent years, allowing for thickness measurement of ultra-thin coatings such as conversion and pre-treatment coatings. These improvements and equipment options will be discussed.
Topics:
Automotive Industry
General Surface Finishing
XRF is a widely accepted non-destructive tool for measuring the thickness and composition of basically any type of metal coating. Typical measurable thickness ranges are on the order of 1-1000 microinches, or .03-25 microns. Recent improvements in detector technology have improved detection limits and consequently lowered the thickness range measurable for very thin coatings. Many metal finishers work with chromate and phosphate type conversion coatings, with alternatives based on zirconium (Zr) and titanium (Ti) becoming more popular over the last decade. All of these coatings are very thin and very difficult to measure with older XRF technology.
Bowman has optimized their XRF systems for maximum sensitivity for measuring conversion coatings with great accuracy and precision. This is possible with the latest in silicon drift detector (SDD) technology which comes standard with every Bowman model. With the ability to focus the x-ray tube with micro-spot precision, small or complex sample geometries can be easily measured. Alternatively, larger samples or Q-panels can be scanned in multi-point programs using the automated sample stage to test for coating uniformity. Different equipment options and performance data from conversion coating application studies will be presented and discussed.