Summary: Make in the light of the mould, repair and problem of the finishing in be being protected beforehand, put forward to use technology of laser frit Fu, undertake to mould surface laser is handled, this technology and photograph of groovy mould finishing technology are compared, have workpiece to be out of shape small, coat quality is stable, exterior hardness, wearability, corrosion resistance raises advanced good point significantly. Keyword: Rehabilitate of surface of mould of laser frit Fu protects foreword to be in modern production, the mould already became large quantities of quantities to produce one of important tooling that all sorts of industrial product and daily expense life taste. As the rapid development of mould industry, the scale that introduces the product that the mould shapes is increasing ceaselessly, also increasing ceaselessly to the demand of the breed of the mould and amount. The pressure of the respect such as the labor power that brings to reduce a large number of production moulds, material resources, resource, use advanced technology to improve mould finishing quality, be in thereby most the service life that the mould prolongs on economic foundation, can reduce the cost of goods not only, raise economic benefits, also reduced resource of finite to the earth material at the same time use up, show important social beneficial result. As the flying development of exterior project technology, the technology of finishing, method, craft also is being improved ceaselessly and innovate, traditional mould finishing technique is like plating of v, brush, thermal spraying to wait, the processing layer that produces as a result of them and metallic matrix are united in wedlock for machinery mostly, adhesion is poorer, and the it is certain to fight fatigue intensity to have influence to workpiece, be restricted certainly on application. Technology of laser frit Fu is a kind of new and high finishing technology, it is used stimulate energy of beam of light, make makings frit Fu forms Tu Fucai at workpiece surface to fight abrasion layer or be fought grind the booked function such as the layer, improve the service life of workpiece. Compare with traditional methodological photograph, this technology has workpiece to be out of shape small, machine effect to lead quality of tall, surface layer to stabilize, exterior hardness, wearability, corrosion resistance raises advanced good point significantly. The experiment of Fu of frit of laser of technology of Fu of 1 laser frit studies only then at 20 centuries 70 time, be in successfully reaction engine impeller piece on with laser besmear Fu face of cobalt radical alloy raised its wearability significantly. Laser frit Fu is a kind of of technology of material surface modified important method, it is to use high-energy laser bundle (104-106 W/cm2) in metallic surface irradiation, fuse quickly through what Tu Fucai expects, expand and rapid and caky, cooling rate achieves 102-106 ℃ / S, in Fu of frit of base material surface one has the stuff of special physics, chemistry or mechanical function, make a kind of new composite material thereby, what lack in order to make up for matrix place is high-powered. Laser frit Fu can ask according to the operating mode of workpiece, the metal that designs all sorts of frit Fu part or metalloid, preparation heat-resisting, be able to bear or endure corrode, wear-resisting, fight the oxidation, surface cladding that fight exhaustion or has character of smooth, report, magnetism. In technology of laser frit Fu, outside affecting the element of coat quality to remove besmear Fu material and base material, if craft parameter protects size of diameter of aeriform sort and discharge, pulverous discharge and the power of position sending pink, laser, pulverous nozzle, scanning speed and wait to also confrontation from temperature of anxious quantity, warm-up the quantity has distinct effect. 2 application citing applies technology of laser frit Fu to handle mould appearance, can be the exterior modified of pair of production moulds that already processed semifinished product already, also can be the exterior rehabilitate of the mould of normal invalidation after a certain quantity of to was being experienced figuration, the fact proves, want to grasp mould tatty pattern correctly only, inside cycle of mould service life, undertake exterior protection is handled in time, can the extension of utmost the service life of the mould. The choice of the parameter of affirmatory, craft of the option that uses key of technology of laser frit Fu to depend on Tu Fucai expecting, technique. Frit Fu material includes to wait from material of fusibility alloy material, composite material, pottery and porcelain, these material have exceedingly good wear-resisting, corrosion resistance can, use with pulverous form normally. The function characteristic of material of Fu of of all kinds frit sees next tables. Laser frit Fu technique and technological process: 1. Alloy is the same as footwork, it is to point to use send makings system technically to send into laser action area directly in the material of alloy of process lieutenant general of laser frit Fu, below the action of laser base material and alloy fuse at the same time, cool next crystallization forms alloy frit cladding. This method process is simple, alloy overall material utilization factor is high, it is good to can charge a sex, implement automation easily, in actual production more use. Its technological process is: → warm-up → sends pretreatment of base material surface makings laser the heat treatment after fused → . 2. Law of the buy before alloy, it is to show the alloy data that will await frit Fu is enclothed beforehand with regular method in material surface, use next stimulate beam of light to scan in alloy overburden surface, make whole alloy overburden and one part base material fused, the fused metal after stimulating beam of light to leave is fast and caky and the alloy frit cladding that forms metallurgy union in base material surface. Its technological process is: Pretreatment of base material surface → beforehand laser of → of warm-up of → of material of buy frit Fu fuses → postheat is handled. The craft parameter of laser frit Fu basically has: Area of speed of laser power, scanning, facula, quantity sending pink. Most mould is in the condition come off work of relatively abominable operating mode condition is made, the protective processing of mould surface appears very important. It is with forging die exemple, hot forging die uses 5CrNiMo commonly or steel of 5CrMnMo alloy tool is made, forging die works below high temperature and certain load condition, operating mode condition is abominable, requirement mould surface needs to have function of exhaustion of good high temperature strength, heat-resisting and wear-resisting property, use finishing technology of laser frit Fu to be able to realize a requirement. The basis heats up the real work circumstance of forging die, the material of exterior besmear Fu of affirmatory hot forging die is carbide compound and pulverous NiCrAl/Cr3C2, technique is the same as footwork for alloy. Specific technology unit process of cargo bandling is as follows: Pretreatment of surface of Fu of frit of ① base material heats base material surface to go to 300-450 ℃ left and right sides oily or go with organic clear lotion oily. Those who use face of base material of purify of gush sand preparation is rustily, make its shag is changed, benefit at adhering to pulverously. ② warm-up heats inside burner, the temperature with make base material surface heats constant, reduce the difference in temperature between base material and frit cladding appropriately with cladding of bring down frit cold shrink the stress of generation. ③ synchronism sends melt into of powdery laser frit to assure frit Fu quality, diameter of speed of power of right choice laser, scanning, facula and quantity sending pink, distributing in order to assure the smooth power density inside laser facula even, make the appearance of the appearance of powdery the later and decadent stage of a school of thought and facula and dimension photograph match, the later and decadent stage of a school of thought of strict control pink and base material, laser bundle 3 person the relative position between. When general power density is 103-108W/cm 2, frit Fu process is in 0. Finish inside 1-1s. The heat treatment after ④ is used heat preservation heats inside furnace, sufficient hind the refrigeration that let oven, in order to eliminate the leftover stress of frit cladding. Machining undertakes ⑤ machining checks finishing quality. Processing of Fu of frit of 3 conclusion laser is a kind of fast and caky technology, can acquire the superior organization property that acquires hard below condition evenly commonly, it does not have any limitation to the requirement of base material, can ask according to performance characteristics the part that designs coating is comprised, on relatively cheap material preparation gives performance exceedingly good the surface layer that has tall union strength, other finishing craft can not be likened to this. However, at present Fu technology still does not have laser frit to win large-scale application in industrial production, because return,basically be be put in the following problem and restrict its to develop. It is processing cost is high, the fixed assets of laser processing system and upkeep are used the photograph is taller to groovy v, thermal spraying, promotion application laser handles a technology, must improving productivity, reduce managing and specific power consumption, valuable data, raise performance characteristics substantially or solved the technical key that solves hard with other method the ability below the premise of the problem comes true. The 2 precision that are processing equipment and stability and the requirement that industrial production uses still have certain space, of the equipment in application be not being stabilized is one of causes that cause defect of quality of frit cladding existence. 3 it is to serve as new technology, the laser with still be had no relatively mature handles optimal craft parameter and coating part reasonable design appears, still need further exploration and research. Be based on same question, this technology is restricted naturally in the promotion on mould manufacturing industry. Although at present technology of laser frit Fu returns the issue that is put on a few application, but the progressively development that studies to laser theory and craft as people, believe in industry in not far regular in the future meeting mining gives its tremendous potential. CNC Milling
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