With the development of processing industries, modern tool materials toward high-precision, high-speed cutting, dry machining and cost other direction. Tungsten carbide knives excellent performance is more occasions alternative to other tool materials. It is a tool material from refractory metal compounds and metal binder made by powder metallurgy. Tungsten carbide knives hardness is HRA89 ~ 94, much higher than the high-speed steel, and has good chemical stability and heat resistance.
From the microscopic point of view, is not rigid but crystal elastomers. And because the composition of different atomic structure of crystals and crystal, its ability to rigid, flexible, crystal strength and impact energy transfer is completely different. When tungsten carbide knives under attack, the impact energy spread from the point of impact to the depths of the material. With the improvement of the impact energy received on the same material impact velocity of the more difficult it is passed to the depths of the material. When reaches a certain impact velocity between the impact energy will gather at a certain distance from the contact point within the lattice, making the atomic vibrations increases. Tungsten carbide knives on macro behave as soft metal like processing properties. At this point the impact velocity is the speed of this critical phase change material superplastic phenomenon produced. At this time cutting this material is ultra-high-speed cutting of critical and must speed. With the cutting speed increases, the underlying chip thickness gradually thinning superplasticity. This is tungsten carbide knives mechanism of deformation at ultra-high speed cutting chips and nature.
In the ultra-high-speed cutting of tungsten carbide knives, metal chips underlying tissue appeared transformation superplasticity phenomenon. Due to the emergence of superplastic deformation force significantly reduced, no hardening, bending deformation of the specimen increased. Many physical phenomena, ultra high-speed cutting, in fact, the transition from plastic to metal material superplastic kind. The main mechanism of action is superplastic metallic materials. As long as the chip after deformation rate and temperature reaches a certain height, the chip will be able to show the underlying transformation superplasticity phenomenon. Therefore, cutting force decreased deformation of the workpiece is reduced, the surface temperature is low, no processing sclerosis. Of course, different metal materials, phase change transition superplastic strain rate and temperature also varies.