Precision machining technology for hard alloy parts

Precision machining technology for hard alloy parts

Hard alloy is an alloy material made from hard compounds of refractory metals and bonded metals through powder metallurgy process. One or more types of carbides and alloys composed of bonded metal drills are often called hard alloys. Precision parts processing plants cannot do without hard alloys.

Cutting is one of the commonly used methods for cutting hard alloy rods, plates, and wires. For grooves or cuts below 1mm, diamond ultra-thin cutting pieces are commonly used for processing.

Diamond resin based cutting blades, with the outer ring as the resin bonded abrasive working layer and the central part made of high-strength and high rigidity metal material, are mostly used for cutting grooves and cutting with medium and large cutting depths.

In the process of turning hard alloy components, the hardness of the tool itself must be higher than the hardness of the workpiece being processed. Therefore, currently, the tool materials for turning hard alloy components are mainly high hardness and high heat resistant non-metallic adhesives CBN and PCD (diamond).

1. For hard alloy parts with a hardness less than HRA90, BNK30 material CBN tool is selected for large allowance turning, and the tool does not break or burn. Hard alloy components with a hardness greater than HRA90 are generally ground using CDW025 material PCD cutting tools or resin bonded diamond grinding wheels.

2. When precision machining grooves above R3 on hard alloys, for those with large machining allowances, BNK30 material CBN cutting tools are generally used for rough machining first, and then ground with grinding wheels. For those with small machining allowance, grinding can be done directly with a grinding wheel, or PCD cutting tools can be used for contour machining.

3. When machining the crescent grooves of hard alloy rolling rolls, CDW025 material diamond carving milling cutters (also known as flying cutters or rotary milling cutters) are used.

For the milling process of hard alloy components, according to customer needs, CVD diamond coated milling cutters and diamond insert milling cutters can be provided for precision part processing, which can replace electrolytic corrosion and electric discharge processes, improve production efficiency and product quality. For example, CVD diamond coated milling cutters can micro mill hard alloys, and the surface roughness can reach 0.073 μ m.

Precision machining