Friction and Wear Properties of Tungsten Carbide Cutting Tools

In each tungsten carbide cutting tool friction processes follow a similar law, namely the initial dynamic friction coefficient have experienced a rapid increase in the transition period from the initial value, and then remained relatively stable and fluctuated in a stable phase characteristics. Initially, under normal loading, the friction surface is only partially asperity contact, a smaller adhesive area, the contact surface of the molecular attraction is small, the friction coefficient is small; as rubbing process, interfere asperity gradually being polished, adhesion area increases, the molecular attraction also increases, resulting in friction coefficient increases. The whole process is the carbide friction contact surface mount constantly, then they continue to cut under shear stress process. Since the surface of Co phase peeling, crushing the sample surface caused by wear, local surface adhesion soon reach a dynamic equilibrium, causing the friction coefficient of the surface is maintained in a more stable range, called the stationary phase.

Tungsten Carbide Cutting Tool Selection

The amount of tungsten carbide cutting tools is reasonable or not choose between a good impact on the ability to play with the machine tool cutting potential in order to achieve high-quality, high yield, low cost and safe operation. Fine car, machining accuracy and surface roughness is higher, and the allowance is not uniform, so choose when cutting the amount of fine cars, should consider how to ensure that the processing quality and maximize productivity on this basis. Therefore, refined car should use a smaller (but not too small) on the back of cut and feed rate, and the use of high performance materials and reasonable tool geometry parameters, in order to improve the cutting speed as possible.

Tungsten Carbide Turning Angle Measurement Geometry

Type tungsten carbide turning into the straight cylindrical head turning, turning outer elbow, partial knives, cutting knives. Carbide Tool geometry measurements need be prepared in advance and require universal tools protractor to measure the turning station. Structure and method of use universal tools protractor station: turning protractor sets can more easily measure the turning angle geometry. It mainly consists of base, column, measuring units, positioning block, the size of the dial, the size of the piece of finger, nuts and other components. Wherein the base and column are the supporting body of the entire structure. Measuring tool on the table, try to be positioning block, may vary when the measuring table or counter-clockwise along together, and can be moved around in the measurement stage positioning block. Large nut rotation can move up and down the slippery body, so that the two pieces of the dial and the means to achieve the desired height. When used, by rotating the front or the bottom or side of the measuring station or thumb piece is measured elements fit closely with the tool, you can read the angle values are measured from the base or dial.

Tungsten Carbide Tools Chipbreakers

In carbide turning the breaker groove can affect the volume of chips become shaped portion, the triangular areas cut surface and the contact surface constituting the cutting edge, the main problem is the presence of energy in this region is sufficient to enable the chips to become a roll. Feed change from portrait to landscape when you feed, will change the flow of chips that had been flowing along the direction perpendicular to the cutting edge of the chip will be converted to tilt in the direction of flow of the blade. Then reduce the amount of rake angle is very small, but because only be provided by a shoulder tungsten carbide tools chipbreakers deformation energy of the chips greatly reduced, so the chip out of elongation, causing it wound to the tool or workpiece on. In this case the need to supplement the energy of the deformable portion, the shoulder can be efficiently used cemented carbide tools, the chipbreaker to get deformed.

Nano Tungsten Carbide Cutting Tool Al / SiCp Composite Material Mechanism

Tungsten carbide cutting tool AlSiCp nano composite material is divided into mechanism of tool wear mechanism analysis, a composite material removal mechanism and cutting parameters influence on tool wear three parts. Because of Al / SiCp SiC particulate material hardness (microhardness HV = 27GPa) higher than tungsten carbide (YG class tool material microhardness HV = 16 ~ 18GPa, nano-carbide WC-7Co microhardness HV = 22GPa), therefore, with tungsten carbide cutting tool Al / SiCp composites quickly when worn or damaged. Before and after the cutting tool flank and observed daily post-processing, there is found to the rake face bright visible white band can be seen under the microscope parallel to the flow direction of the chip grooves, since the chip contains a lot of SiC particles, in before flowing along the flank when the chips, the chip on the bottom of the SiC particles generated rake micro-cutting role in the formation of the grooves.

Nano Tungsten Carbide Cutting Tool Al / SiCp Composites

Tungsten carbide is a novel nano-materials, the grain size is about 200nm, like ordinary tungsten carbide does not have high brittleness, easy to chipping, impact intolerance disadvantage, has a high fracture toughness and a very high bending strength also has high hardness and good wear resistance, high thermal conductivity and low coefficient of friction, suitable for the production of tools, and has broad application prospects. However, application of nano tungsten carbide cutting tool Al / SiCp composites, has not been reported. Therefore, to explore the feasibility of application of nano tungsten carbide cutting tooling Al / SiCp has a very important practical significance.

Nano Tungsten Carbide Cutting Tool Manufacturing

Experiment with SPS (discharge plasma sintering method) successfully prepared nano tungsten carbide wc-7Co, using the intercept method WC grain size were tested, the results showed that the average particle size of nano-products of tungsten carbide WC-7Co at about 200 nm. When using nano-carbide WC-7Co making nano tungsten carbide cutting tools, tungsten carbide nano first round sintered WC-7Co rough cut with a knife Cutting block, then Japan and around the flank of the blade were used W40 , W10, W3.5, W1 diamond grinding coarse grinding, fine grinding, ultra-fine grinding and non-feed grinding on ELID (Electrolytic In-process Dressing, ELID) ultra-precision surface grinder, finally succeeded to obtain nano tungsten carbide WC-7Co knife block.