Method for assessing the result of a surface treatment performed on a workpiece by particle blasting

A method for assessing a result of a surface treatment carried out on a workpiece by means of particle blasting, wherein the method comprises:

• (1) recording of an optical measuring method a surface machined by means of particle blasting in a spatially resolved manner and, in each case for spatially resolved measuring points, determining:
• a. a surface level, and
• b. a value of a local gradient with respect to adjacent measurement points;
• (2) comparing the determined surface level with a target level expected for an untreated workpiece at a measuring location of a measurement point, and determining a deviation, and either:
• (3a.1) identifying as measuring points not hit by a particle of the particle beam such measurement points for which:
• a. the determined surface level as per (1) a. is above a level located about a predetermined height threshold value lower than the target level, and
• b. the doted determined gradient as per (1) b. falls below a predetermined gradient threshold value;
• (3a.2) determining a portion of the surface that is not covered by the particle beam by dividing the number of measuring points identified as not hit by a particle of the particle beam as per (3a.1) by the total number of determined measuring points, and/or
• (3b) determining a distribution of the deviation and a Weibull distribution parameter thereof, wherein an excessively low hit of the workpiece with the particle beam is assumed when the Weibull parameter is below a predetermined value;
• wherein one of a white light interferometry, laser light section sensors, a stereo chamber system and/or a shape-by-shading method is used as the optical measurement method;
• and
• wherein the spatially resolved recording of the surface machined by means of particle blasting is carried out with the aid of an optical measuring device.