Exceed strong cutting tool the laser ablation treatment of three-dimensional profile

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To tool manufacturer, the three-dimensional profile that machines PCD, PCBN, hard alloy and cutting tool of pottery and porcelain (if decide the geometrical form of bits stage) it is a kind of unique challenge. These challenges restricted the dimension precision of the gain capacity that exceeds strong cutting tool and its profile. Discharge is machined (EDM) it is preparation exceeds strong cutting tool the treatment method with three-dimensional the most commonly used profile, but this method is put in a few blemish, if the limitation to tool electrode wear extent, treatment is periodic long, can machine conductor to wait only. Laser ablation treatment is a kind of EDM that has appeal quite replaces craft. Because this craft need not wear away to the tool,undertake compensating, can raise material purify rate again at the same time, because this suits very much,machine three-dimensional profile. In addition, laser ablation does not ask workpiece material has conductivity, because this is OK,treatment pottery and porcelain is mixed other non-conductive n material. The profile of mould of the station breaking bits that this method can use at treatment to exceed strong cutting tool, punch, and all sorts of geometry figure that fixed position and locking support with Yu Ga on cutting razor blade. Laser ablation is to carry burn off means or aerification kind from material of workpiece surface purify. When burn off is machined, stimulate beam of light to undertake burn off to workpiece surface along continuous method, as similar as typical sculpture or cutting treatment. Aerification treatment is to use laser pulse, the workpiece material aerification of specific place, form little sunken speech on workpiece thereby. Sunken antrum dimension is the function that stimulates dimension of beam of light and its focus diameter. The power of laser is greater, the sunken antrum measure that treatment gives is larger, material purify rate is higher also. However, this does not mean laser power to had been jumped over greatly more. Stimulate dimension of beam of light to still must consider to machine the other property of the machine tool certainly, and the surface that be mixed by the dimension precision of treatment profile is bright and clean spend a requirement. The laser of solid of diode pump riverside that center of the Spectra 820 that German Wendt company produces laser beam machining uses the position to secure, its stimulate beam of light to have very tall focusing precision, can form the focal diameter of 20 μ M, this means it to be able to machine a diameter to make an appointment with 20 μ M, deepness to restrict the sunken speech of 10 μ M. Sunken antrum deepness may affect treatment the surface is bright and clean degree. Pass the pulse mode of adjusting control laser, can control sunken antrum deepness. Wendt company was developed " accept rice selects a technology surely " algorithm will control laser pulse mode, the basis is machined the different characteristic of profile, the athletic way of X axis, Y axis and Z axis also each are not identical. The illuminant position of center of Spectra laser beam machining keeps changeless, be located in the workpiece that stimulates lower part of beam of light to move by process designing method. In typical laser beam machining, the mobile acceleration of workpiece exceeds 3g. Treatment dimension precision can amount to ± 0.

010 μ M, can obtain grind treatment with essence of life similar material purify rate and surface are bright and clean degree. With treatment parameter (be like speed of emery wheel diameter, emery wheel) constant change and the grinding treatment that affect each other are different, the treatment parameter of laser ablation is had can forecast a gender, and won't mutual influence. Material purify rate gets the control of laser pulse frequency and mode. As a result of every laser pulse metropolis aerification drops material of a small workpiece, the frequency of laser pulse is accordingly taller, material purify rate is higher also. The limits of frequency of programmed control pulse of center of Spectra laser beam machining is 0 - 100 KHz, to achieve good appearance bright and clean degree, use treatment of complete frequency limits normally. The surface is bright and clean degree of function that is laser pulse frequency and motion of machine tool axis, both all can ask to undertake adjustment according to the geometrical profile of cutting tool. Be led to affect to material purify by profile of treatment cutting tool or appearance of geometry of the stage that break bits very big. Spectra machining center uses a kind " circuitous " process designing technology comes purify workpiece material. When be being machined with this technology, the straight path around that stimulates the axis of workpiece edge Y below beam of light is mobile. When the terminus that stimulates beam of light to machine cutting tool profile, workpiece can go to below one to machine the position along X axis sideslip, begin to move along Y axis around again. Workpiece moves line by line continuously with this kind of means, till finish,machine to the ablation of whole face. Next, it is certain to stimulate axis of Z of edge of beam of light to drop height, undertake machining on next horizontal. In a word, the treatment means of Spectra machine tool is: Workpiece presses process designing method line by line translation, and stimulate beam of light to chase a layer to be down shift, till complete treatment gives whole profile. The insular state that if be gone up to have bits stage to design middling by treatment profile,sees is raised, should use optimized material purify strategy, machine cycle time in order to shorten. Typical material purify strategy includes " jump function " (namely from insular shape raised upper part is jumped over, in jump method comparing bypasses the treatment of raised place is used when way is shorter) and " shortcut function " (the shortest way that be planned to carry different geometry element namely by treatment software, although operate the program way of personnel staff,likelihood and this differs) . Once open these functions, they can move automatically. The hardness of workpiece material also can affect material purify rate. Nevertheless, although hard alloy, pottery and porcelain, PCD is mixed the hardness of PCBN material each are not identical, but its material purify is led mutual between the difference is not big, because,this is material hardness must six to one (if hard alloy is opposite at mild steel) , ability will be right material purify rate produces bigger effect. In laser ablation treatment, the surface is bright and clean degree (or exterior integrality) also have can charge a sex -- mention before no less than, focusing quality and laser power can control the appearance bright and clean degree. In addition, with Spectra software choice treatment parameter also is met influence surface is bright and clean degree. Develop mode and software character through frequency of power of adjusting control laser, pulse, arteries and veins, the treatment surface surface roughness of PCD and PCBN cutting tool can achieve Ra0.

2 μ M, the exterior surface roughness of hard alloy cutting tool can achieve Ra0.

45 μ M. Laser ablation is a kind of noveller treatment technology, in exceed hard data (include foregone the hardest diamond) three-dimensional profile nicety machines a domain to have development latent capacity extremely. CNC Milling