Cutting Quality of the Kitchen-knife (Part 1)

Deformation in a Piece of Fuse cut by Kitchen-Knife

Abstract

The cross-section of the kitchen-knife having the thin cutting edge were observed and photographed by means of travelling microscope.
It was observed that the very edge of the kitchen-knife was not formed by two blade surfaces but formed by two other surfaces. The angle contained by these two surfaces that formed the edge was larger than that which should be formed by the two surfaces of the blade. In the cross-section of the kitchen-knife the angle contained by the line of the sharp edge surface and the line connecting the very edge point and the intersecting point of the lines of the blade surfaces was larger than the angle contained by the dull edge line and the connecting line stated above.
The strains induced in the piece cut by the kitchen-knife were measured on both sharp edge side and dull edge side. It was detected that the deformation on the sharp edge side was greater than that on the dull edge side.