High Hardness Tools Selection Guide
This product has been discontinued and removed from our shelves.
As science and technology continue to advance, engineering materials with high hardness and durability improve. Traditional turning techniques can hardly fulfill the machining of some of these materials. Coated tungsten carbide, ceramic, and PCBN materials are used to take advantage of high temperature hardness, wear resistance, and thermal-chemical stability. The outstanding properties of these hardmetal cutters are used to increase productivity and effectiveness when it comes to machining.
The parameters of hardmetal cutters and requirements to the process system
- The selection of turning parameters. The higher the hardness of a work piece, the slower the cutting speed should be. The appropriate cutting speed should be controlled under 80-200 m/min when using hardmetal cutters. The common speed should in the range of 10-150 m/min. The cutting speed should keep under 80-100 m/min when adopting large cutting depth or interrupted cutting material with high hardness intensely. Generally, the cutting depth is between 0.1-0.3 mm. Machining work pieces with low surface roughness should choose a small cutting depth. Certainly the value cannot be as low as possible. It should suit the condition. The feed rate is generally between 0.05-0.25 mm/r, the specific value need take the surface roughness and productivity into account. When the surface roughness Ra=0.3-0.4 μm, it is more economical using hardmetal cutters.
- Requirements to process system. There is nothing special for turning or turning center when using hardmetal cutters to hard turning except for choosing appropriate cutting tool. The cutter can be applied to hard turning as long as the stiffness of turning or turning center is enough and the precision and surface roughness would meet requirements. Common methods to keep turning operation stable and continuous are adopting rigid clamping device and medium rake cutter. It is feasible for hard turning only if work pieces can keep location, support and rotation under stationary condition.
After years of researching and exploring, we have made great progress in hardmetal cutters. However, the application is still limited. There are some possible reasons:
- The manufacturer and operator are not familiar with the effectiveness of hardmetal cutters. It is generally considered that hard material can only be used for grinding and the cost is too high. In the beginning, the cost of hard turning cutters are higher than normal carbide cutters, the price of PCBN is more than ten times. However, the average cost is lower than grinding and the profit is much higher than carbide cutters.
- There is much to study on the machining mechanism of hardmetal cutters.
- The technical standard is insufficient to guide production.
In order to generalize the high efficiency and green techniques, we need to continue researching machining mechanisms, training on the knowledge of machining operation of hardmetal cutters, success cases, and carry out strict operation specification.