Electron Microscope technology to check for surface defects

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http://www.caradvice.com.au/135205/f...rface-defects/

Ford engineers use Scanning Electron Microscope technology to check for surface defects
By Brett Davis | August 29th, 2011

Ford engineers are using Scanning Electron Microscope (SEM) technology to observe their vehicle’s panel surfaces under fine detail to make sure there are no defects. The intricate investigation methods are usually used by forensic scientists and can detect surface defects well beyond what the naked eye can pick up.



The SEM technology allows Ford engineers to ensure critical materials are defect-free by giving them extra-close detailed imagery of any surface. To give you an idea of its power, the average human hair is around 0.07mm thick. The SEM scanner is able to provide details of objects under 0.000001mm in size.

The SEM scanner does this by using electron beams which are bounced off the material’s surface, rather than light waves like a more conventional microscope. Roger Davis from Ford of Europe’s materials engineering and testing department recently said,

“We need to investigate possible reasons why a development part may not meet our stringent requirements. In some cases that reason can be the smallest anomalies, something that can be found by using the Scanning Electron Microscope.

“The machine can magnify a part by up to 200,000 times and make it look quite surreal, but to the trained eye any defects become quickly apparent at these levels of magnification.”

Ford has begun using the scanners for development and testing of its materials that are used on new Ford vehicles.