The grinding balls samples should be prepared such way, that their properties will not changed as a result of mechanical or other processing.
The grinding on a surface grinding machine is the best way to prepare the grinding balls surface for hardness measures.
A special matrix has created for steel grinding balls. From 2 to 5 grinding balls placed in matrix and simultaneous polish them.
The grinding balls placed in the matrix and fixed there to avoid the area skewing under hardness measurement.
Surface grinding (surface polishing) includes the following movements: the cutting tool rotation – a grinding wheel PP 25A 250х40х76 25СМ, the grinding balls feeding by longitudinal and cross way, the grinding balls movement toward cutting grinding wheel.
Coolant supplies to the contact point of grinding balls and grinding wheel during surface grinding. Coolant helps to avoid the surface overheating and the hardness measurement results distortion.