Hardness of 9H (9H hardness 9 = corundum (sapphire) grinding hardness 1000 according to Rosiwal only the diamond is harder = 10H) Please note that this film is made from tempered real glass and deliberately left 1-2 mm of space to the edge of the smartphone. Since smartphone displays are slightly rounded and therefore the film cannot lie there, this distance was deliberately kept. This quenching causes the surface to solidify and the external dimensions of the component now change only comparatively little. However, the warmer core continues to contract even more strongly because the thermal expansion above the transformation point is significantly higher than below it. However, a workpiece treated in this way can no longer be cut in a non-destructive manner, as is possible with untre