Cemented carbide rotary files are mainly composed of high-hardness, refractory metal carbides (WC, TiC) micron powders, cobalt (Co), nickel (Ni), molybdenum (Mo) as binders. Or powder metallurgy products sintered in a hydrogen recovery furnace. The carbides, nitrides, borides, etc. of group ⅣB, ⅤB, and VIB metals are collectively called hard alloys because of their extremely high hardness and melting point.
Teach you principles of selection.
1 Selection of cross section shape of hard alloy rotary file
The cross-sectional shape of carbide rotary file cutter should be selected according to shape of filed part, so that two shapes are compatible. When filing inner arc surface, you should choose a semicircular file or a round file (small diameter workpiece); when filing inner corner surface, you should choose a triangular file; when filing inner right-angle surface, you can choose a flat file or a square file. When using a flat file to file inner right-angled surface, pay attention to make narrow surface (smooth edge) of file without teeth close to inner right-angled surface to avoid scratching right-angled surface.
2 Choice of file tooth thickness
The thickness of the teeth of file should be selected according to size of workpiece allowance, machining accuracy, material properties. Coarse-tooth files are suitable for machining workpieces with large allowance, low dimensional accuracy, large geometric tolerances, large surface roughness values, soft materials; otherwise, fine-tooth files should be selected. When used, it should be selected according to required machining allowance, dimensional accuracy and surface roughness of workpiece.
3 Selection of alloy file size specifications
Carbide rotary file size specifications should be selected according to size of the workpiece to be processed and machining allowance. When processing size is large and margin is large, file of large size should be used, and file of small size should be used on contrary.
4 Selection of file tooth pattern
The tooth pattern of tungsten steel grinder file should be selected according to nature of material to be filed. When filing soft materials such as aluminum, copper, mild steel, etc., it is best to use a single-tooth (milling tooth) file. The single-tooth file has large rake angle, small wedge angle, large chip pocket, chip is not easy to block, and cutting edge is sharp.