Localizing micro-defects on rough metal surfaces

• In this paper we present a study of reflectance measurements to a direct metrological problem. Our aim is to estimate progressive surface wear by detecting minute defect development in surface microtopography on Ra 0.7 μm rough stainless steel surfaces subject to mechanical wear from hard particle deposits on a metal bar. The investigation was carried out by using a standard CMOS digital camera with a macro objective. It demonstrates how surface scattering measurements can provide a viable alternative in circumstances where traditional roughness measurement techniques fail to deliver the expected results and, due to certain restraints, laboratory-type surface measurements are not applicable either. Our work is based upon measuring variations in the amount and direction of scattered light, reflected from the inspected surfaces, featuring microirregularities. We will show that it is possible to identify the extent of surface flaws by statistically evaluating the recorded brightness information. The developments in this paper can provide basis for a future quality control system devoted to on-line surface measurements of micro components.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Produktionsteknik, arbetsvetenskap och ergonomi (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Production Engineering, Human Work Science and Ergonomics (hsv//eng)

TEKNIK OCH TEKNOLOGIER  -- Nanoteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Nano-technology (hsv//eng)

Keyword

surface roughness

defect assessment

reflectance

light scattering

digital camera

TECHNOLOGY

TEKNIKVETENSKAP

SRA - Produktion

SRA - Production

Publication and Content Type

ref (subject category)

kon (subject category)