The residues embedded in the substrate surface in grit-blasted specimens can be examined by SEM ( http://www.sciencedirect.com/science/article/pii/S0301679X02000099 Hydrodynamic profiling and grit blasting of low-carbon steel surfaces, Tribology International, Volume 35, Issue 4, April 2002, Pages 271–281) (or http://researchbank.swinburne.edu.au/vital/access/manager/Repository/swin:2185?queryType=vitalDismax&query=In+residues+embedded+in+the+substrate+surface+in+grit-blasted+specimens+can+be+examined+by+SEM&y=23&x=21)
Could residues embedded in the substrate surface in grit-blasted specimens be examined by optical microscopy or any other method?