Preparation of Non-Metallic Materials for Examination under an Optical Microscope.

Tests carried out show that the comparatively elaborate procedures necessary to produce thin polished sections can in many cases be satisfactorily replaced by more economical machining techniques. Considerable time and cost savings have been made possible by preparing monolithic specimens using a high-speed milling machine and microsections using a low-speed saw. This applies particularly to the use of the low-speed saw in quality control for components made of glass fiber reinforced polyesters. Another important application is the preparation of specimens of synthetic resin-impregnated graphite for corrosion resistance tests using a high-speed milling machine.