Cemented carbide is an alloy material made of hard compound of refractory metal and bonding metal through powder metallurgy process. An alloy of one or more of the carbides and a bond metal is often called a cemented carbide.
Precision parts processing plants are even more inseparable from cemented carbide. Cutting is one of the common ways to cut cemented carbide bars, plates and wires. For grooving or cutting below 1mm, diamond ultra-thin cutting blades are often used for processing.
The diamond resin matrix type cutting blade, in which the outer ring belt is the resin bond abrasive working layer, and the central part is made of high-strength and high-rigidity metal material, which is mostly used for grooving and cutting of medium and large cutting depths. In the process of turning cemented carbide parts, the hardness of the tool itself must be higher than the hardness of the workpiece to be machined. Therefore, at present, the tool materials for turning cemented carbide parts are mainly made of high-hardness, high-heat-resistant non-metallic binders CBN and PCD (diamond). ) as the main.
- Carbide parts whose hardness is less than HRA90, choose BNK30 material CBN tool for large allowance turning, and the tool will not break or burn. Carbide parts with hardness greater than HRA90 are generally ground with CDW025 PCD tools or resin-bonded diamond grinding wheels.
- When machining the grooves above R3 for precision parts of cemented carbide, for those with large machining allowances, generally use BNK30 material CBN tools for rough machining, and then use grinding wheels for grinding. For small machining allowances, it can be directly ground with a grinding wheel, or a PCD tool can be used for profiling.
- When ribbing the crescent groove of the cemented carbide roll, the diamond engraving and milling cutter (also known as flying cutter, rotary cutter) of CDW025 material is used. For the milling processof cemented carbide parts, according to customer needs, CVD diamond coated milling cutters and diamond insert milling cutters can be provided for precision parts processing, which can replace electrolytic corrosion and EDM processes, improve production efficiency, and product quality, such as micro-milling of cemented carbide with CVD diamond-coated milling cutters, the surface roughness can reach 0.073 μm.