At present the commonly used polishing method has the following several kinds: <BR>1.1 the mechanical buffing <BR> mechanical buffing is after the cutting, the material surface plasticity distortion removes polishes the double wedge is obtained the slick polishing method, generally uses the oilstone strip, the sheep whorl, the sandpaper and so on, by the manual operation primarily, the peculiar part like solid of revolution surface, may use the turnplate and so on auxiliary means that the surface quality requests the method which high may use ultra researches in thorough detail throws. Ultra researches in thorough detail throws is uses specially made the grinding tool, in includes the grinding compound to grind throws in the fluid, squeezes, in the work piece is processed on the surface, makes the high speed rotary motion. May achieve Ra0.008 Mu m using this technology the surface roughness, is in each polishing method is highest. The optical lens mold often uses this method. <BR>1.2 the chemical polishing <BR> chemical polishing is lets the material the part concave part preferential solubility which the surface microscopic protrudes in the chemical mediator, thus obtains slick. This method's principal advantage does not need the complex equipment, may polish the shape complex work piece, may simultaneously polish many work pieces, the efficiency is high. Chemical polishing's core question is the polishing solution configuration. The chemical polishing obtains the surface roughness is several 10 Mu m generally. the <BR>1.3 electrolysis polishes the <BR> electrolysis polishing basic principle and the chemical polishing is the same, namely depending on the selective dissolved material surface small projecting portion, causes the surface to be smooth. Compares with the chemical polishing, may eliminate the cathodic reaction the influence, the effect is good. The electrochemistry polishing process divides into two steps: <BR> (1) the macroscopic leveling dissolution product proliferates to the electrolyte, material surface geometry rough drop, Ra > 1 Mu m. <BR> (2) the glimmer smooth anodic polarization, the superficial radiance enhances, Ra < 1 Mu m. the <BR>1.4 ultrasonic wave polishes <BR> to put in the work piece in the grinding compound suspending liquid and puts in together in the supersonic wave field, depends upon the ultrasonic wave the vibration function, causes the grinding compound in work piece surfacing polishing. The ultrasonic machining macroscopic strength is small, will not cause the work piece to distort, but the work clothes manufacture and the installment will be difficult. The ultrasonic machining may with chemistry or the electro-chemical means union. In the solution corrodes, in the electrolysis foundation, exerts the ultrasonic wave vibration agitation solution again, causes the work piece surface dissolution product to be separated from, the superficial nearby corrosion or the electrolyte are even; The ultrasonic wave can also suppress the corrosion process in the liquid cavitation, favors the surface luminously. the <BR>1.5 fluid polishes <BR> fluid polishing is the abrasive washout work piece surface which the dependence high speed flowing liquid and carries achieves polishing the goal. The commonly used method includes: Grinding compound spraying processing, spouting of liquid processing, hydrodynamics attrition and so on. The hydrodynamics attrition is by the hydraulic pressure actuation, causes to carry the abrasive the liquid medium high speed reciprocation to wind through the work piece surface. The medium mainly uses is comparing the low pressure obscene good special compound (polymer shape material) and mixes the grinding compound to make, the grinding compound may use the silicon carbide powder. the <BR>1.6 magnetism attrition polishes <BR> magnetism attrition polishing is uses the magnetic grinding compound to form the grinding compound under the magnetic field function to brush, to work piece abrasive machining. This method processing efficiency is high, the quality is good, the working condition easy to control, the working condition is good. Uses the appropriate grinding compound, the surface roughness may achieve Ra0.1 Mu m. <BR> polishing which said in the plastic mold processing the surface polish which requests with other professions in has the very big difference, strict, mold's polishing should be called the mirror surface processing. It not only to polishes itself to have the very high request, and to the superficial smoothness, evenness as well as the geometry precision also has the very high standard. The surface polish only requests to obtain the luminous surface generally then. The mirror surface processes the standard divides into four levels: AO=Ra0.008 Mu m, A1=Ra0.016 Mu m, A3=Ra0.032 Mu m, A4=Ra0.063 Mu m, as a result of methods and so on electrolysis polishing, fluid polishing is very difficult the accuracy control components the geometry precision, but method and so on chemical polishing, ultrasonic wave polishing, magnetism attrition polishing surface qualities cannot meet the requirements, therefore precision mold's mirror surface processing by mechanical buffing primarily. <BR>2.1 mechanical buffing main routine <BR>, if wants to obtain the high grade polishing effect, most importantly must have the high grade oilstone, the sandpaper and the diamond grinds polishing tools and the auxiliary and so on paste. But polishes the procedure the choice to be decided after the earlier period processing the surface condition, like the machine-finishing, the electric spark machining, rub processing and so on. Mechanical buffing's general process is as follows: <BR> (1) throws thickly after the mill, the electric spark, rubs and so on craft surfaces to be possible to choose the rotational speed carries on polishing in 35 000 - 40 000 rpm revolving surface buffing machines or the ultrasonic wave grinder. The commonly used method has use diameter PHI 3mm, the WA # 400 wheel elimination white electric spark level. Is the manual oilstone attrition, strip oilstone coaling painter's shop for lubricant or cooling agent. The use order generally is #180 ~ #240 ~ #320 ~ #400 ~ #600 ~ #800 ~ #1000. Many mold manufacturers choose for the save time from the #400 start. <BR> (2) half fine throws half fine throws mainly uses the sandpaper and the petroleum. Sandpaper's serial number is in turn: #400 ~ #600 ~ #800 ~ #1000 ~ #1200 ~ #1500. In fact the #1500 sandpaper only uses to be suitable for the hard molding tool steel (above 52HRC), but is not suitable for the pre-hard steel, because will like this possibly cause the pre-hard steel stock surface burn. <BR> (3) fine throws fine throws the main use diamond to grind the paste. If or grinds the paste with the polishing feltless polishing bob mix diamond abrasive powder to carry on attrition, then the usual attrition order is 9 Mu m (#1800) ~ 6 Mu m (#3000) ~3 Mu m (#8000). 9 Mu m diamonds grind the paste and the polishing feltless polishing bob may use for to remove #1200 and the #1500 number sandpaper stay behind send the shape polishing scratches. Then uses to stick the felt and the diamond grinds the paste to carry on polishing, the order is 1 Mu m (#14000) ~ 1/2 Mu m (#60000) ~1/4 Mu m (#100000). <BR> accuracy requirement above 1 Mu m (including 1 Mu m) the polishing craft a clean polishing indoor then carries on the mold Processing workshop. If carries on the preciser polishing essential absolute pure space. The high precise glazed surface which the dust, the smog, after a leather meal and the mouth froth has the possibility to discard several hour work, obtains. in the <BR>2.2 mechanical buffing must pay attention question <BR> should pay attention to the following several points with sandpaper polishing: <BR> (1) needs to use the soft wooden bat or the bamboo stick with sandpaper polishing. When polishing disc or spherical surface, uses the soft wooden bat to be possible the better coordinate disc and the spherical surface radian. But hard wooden staff likely cherry, is suitable for smooth superficial polishing. Repairs and maintains wooden staff's terminal to enable its to maintain with the steel stock surface shape tallies, like this may avoid the wooden staff (or bamboo strip) the acute angle contact steel stock surface creates the deep scratch. <BR> (2), when uses in exchange the different model the sandpaper, the polishing direction should transform 45 ° ~ 90 °, after like this preceding kind of model sandpaper polishing, stays behind the stripe shadow then distinguishes. Before trading the different model sandpaper, must use 100% pure cottons to moisten takes the ethyl alcohol and so on cleaning liquid to carry on careful cleaning to the glazed surface, because a very small gravel keeps the entire polishing work which the surface can destroy goes. Changes into from sandpaper polishing when the diamond grinds paste polishing, this clean process is similarly important. Before polishing continues carries on, all pellets and the petroleum must completely clean clean. <BR> (3) to avoid abrading and the burn work piece surface, when uses #1200 and the #1500 sandpaper carries on polishing must be specially careful. Therefore has the necessity to load a light load as well as to use two step polishing law to carry on polishing to the surface. Carries on when polishing with each kind of model's sandpaper should carry on two polishing along two different directions, between two directions each time rotates 45 ° ~ 90 °. <BR> diamond attrition polishing should pay attention to the following several points: <BR> (1) this kind of polishing must carry on under the light pressure is specially as far as possible polishes the pre-hard steel stock and with grinds time thin paste polishing. When uses #8000 grinds paste polishing, the commonly used load is 100~200g/cm2, but must maintain this load accurate very difficult to achieve. For easier to achieve this point, may make one on the wooden staff thin and the narrow handle, for instance adds sheet copper; Or slices a part on the bamboo strip to cause it to be softer. This may help the control polishing pressure, guaranteed that the mold surface pressure excessively will not be high. <BR> (2), when the use diamond grinds polishing, is not only the active face request is pure, worker's both hands must careful clean. <BR> (3) each time polishes the time not to be long, the time is shorter, the effect is better. If the polishing process will carry on long will have created “the cedrat” and “the pitting”. <BR> (4) to obtain the high grade polishing effect, easy to give off heat the polishing method and the tool should avoid. For instance: Buffs polishing, buffs the quantity of heat which produces to be very easy to create “the cedrat”. <BR> (5) works as when polishing process stop, guaranteed that the work piece surface pure and careful elimination all abrasives and the lubricant are important, afterward should spray a mold antirust coat in the surface. because <BR> the mechanical buffing mainly depends completes artificially, therefore the polishing technology affects the polishing quality at present the primary cause. In addition, but also before the mold material, the polishing surface condition, the heat treatment craft and so on concerns. The high quality steel products are obtain the good polishing quality the prerequisite, if the steel products skin hardness uneven or in the characteristic has the difference, often will have the polishing difficulty. In the steel products each inclusion friendly kondow does not favor polishing. the <BR>3.1 different degree of hardness to polishes the craft the influence <BR> degree of hardness markup to cause the attrition the difficulty to increase, but after polishing the roughness reduces. As a result of degree of hardness markup, must achieve the polishing time which the low roughness needs to grow correspondingly. Simultaneously degree of hardness advances, polishes the excessive possibility to reduce correspondingly. the <BR>3.2 work piece surface condition to polishes the craft the influence <BR> steel products in the cutting machine-finishing stave process, the surface layer because of the quantity of heat, the internal stress or other factors damages, cutting parameter not, when will affect the polishing effect. After electric spark machining's surface is more difficult than after the standard machinery processing or the heat treatment surface to grind, therefore before the electric spark machining ended, should use the fine guiding rule electric spark to repair and maintain, otherwise the surface will form the hardened thin layer. If the electric spark finishes the guiding rule to choose improper, the heat affects the level the depth to be possible to reach 0.4mm most greatly. The hardened thin layer's solidity ratio matrix hardness is high, must remove. Therefore is best increases together the rough grinding processing, eliminates the damage surface layer thoroughly, constitutes a piece of average rough metal surface, provides a good foundation for the polishing processing. the <BR> abrade and the sand blasting difference <BR> abrade is the use high speed revolving impeller throws the small steel pill or the small hard pill hits high speed the components surface, therefore may except the components surface oxide layer. Simultaneously the steel pill or the hard pill high speed hit components surface, causes the components surface the crystal lattice distortion to distort, makes the skin hardness to advance, is carries on the cleaning up to the components surface one method, the abrade often uses for the casting surface the cleaning up or carries on strengthened processing to the components surface. the <BR> general abrade uses in the regular shape and so on, several throw the high and low about same place, the efficiency is high, the pollution is small. <BR> repairs, the ship-building industry, the abrade, the sand blasting is the universal use. But regardless of is the abrade or sand-blasts, is uses the compressed air the form. Certainly is not the abrade must with the impeller which revolves high speed may not. In repairs, the ship-building industry generally speaking, abrade (small steel pill) multipurpose before steel plate pretreatment (painting stain removal); (What the sand blasting repairs, ship-building industry with is ore) multipurpose in the formation ships or the partition, the function is removes steel plate's on old paint and the rust, paints. Is repairing, the ship-building industry, the abrade, the sand blasting leading role is increases the steel plate painting paint the adhesion. not only the <BR> casting cleaning up uses the abrade actually, carries on the drum clear granulated substance first generally regarding the big-ticket item, after is the casting rising head excision, places in the drum to roll, collides mutually by the components in the drum, majority of falls clear the first superficial granulated substance carries on the abrade or the rotoblast again. the <BR> abrade meatball size is 1.5mm. the <BR> research indicated that speaking of the destruction, when metallic material surface existence tensile stress the specific compressive stress wants easy many, when shows the delivering in person compressed stress, the material fatigue life enhances greatly, therefore, and so on easy endurance failure's part usually to use the rotoblast regarding the axis class to form the superficial compressed stress, enhances the product life, in addition, the metal metallic material to stretches is very sensitive, this is the material stretch strength ratio compressive strength low many reasons, this is also the metallic material (submits generally with the longitudinal strength, anti-pulls) expresses the material performance reason. <BR> we ride daily automobile's steel plate's working surface is strengthens with the rotoblast, may remarkable enhance the material the anti-fatigue strength. the <BR> abrade is leads impeller body revolving with the electrical machinery, depending on the centrifugal force function, (has the diameter in 0.2~3.0 meatball casts pill \ to cut pill \ stainless steel pill and so on) to throw to the work piece surface, enables the work piece the surface to achieve certain thick making, causes artistic which the work piece changes, or is changing the work piece the welding tensile stress is the compressed stress, enhances the work piece the service life. Uses in machinery's majority domains nearly, repairs shipbuilding \ automobile spare part \ airplane part \ arms tank surface \ bridge \ steel structure \ glass \ steel plate \ pipeline \ and so on. The sand blasting (pill) is takes the power with the compressed air spurts the diameter in 40~120 goal granulated substance or 0.1~2.0 about pill to the work piece surface, enables the work piece to achieve the similar effect. A pill grain of size is different, the processing effect which achieves is dissimilar. Key proposed: The rotoblast can play the strengthening similarly the role. Now the domestic equipment entered an erroneous zone, thinks only then the abrade to be able to achieve strengthened the goal. What the American \ Japan's enterprise uses in strengthening is throws the rotoblast and uses! Has each superiority respectively. For instance gear such work piece, the abrade the pill angle is unable to change likely, can only use the frequency conversion to change the initial velocity. But it processes the quantity is big, the speed is quick, but the rotoblast happen to is opposite in it, the abrade effect does not have the rotoblast effect to be good. the <BR> sand blasting is blows high speed using the compressed air the quartz sand carries on to the components surface the cleaning up one method. In the factory also calls the air sand blower, not only derusting, but may also while convenient the oil removing, to paint is useful. Commonly used in components surface stain removal; (Small wet sand which market sells to the components surface finish is this use, sand grains usually is corundum, medium is water); In the steel structure, the application high-strength bolt carries on the joint is one quite advanced method, because the excel in joint is uses between the junction plane the friction power transmission, therefore to unifies superficial the quality requirement to be very high, by must use the sand blasting to carry on processing to the union surface. <BR> spurts the sand to use in the shape being complex, easy to use the manual stain removal, the efficiency not to be high, the scene environment is not good, the stain removal is non-uniform. the <BR> common sand has each kind of specification sand blasting gun, so long as is not the specially small box body, may put the gun hits cleanly. the <BR> pressure vessel's complete set of products - shell cover uses the sand blasting way elimination work piece surface the oxide skin, the quartz sand diameter is 1.5mm~3.5mm.<BR> has one kind of processing is makes the carrier using the water, leads the emery to process the components, is one kind of sand blasting. the <BR> abrade and the sand blasting can have the cleanup decontamination to the work piece the goal, the goal prepare for under foreword, namely must guarantee the evil ways working procedure roughness request, also some to want superficial the uniformity, the rotoblast has the invigoration effect to the work piece, the sand blasting is not obvious. Generally the rotoblast is the small steel ball, the sand blasting is the quartz sand. According to various requirement, subtitle number. the <BR> precision casting is using the sand blasting, the abrade nearly daily. <BR> supplemented: the <BR>1. abrade and the sand blasting are the surface treatments, but was not says only then the casting only then abrade <BR>2. to sand-blast the major function is the superficial stain removal, except oxide skin and so on, after for instance heat treatment components, but the abrade function and the function were many: Not only stain removal, except superficial oxide skin, but also enhances the surface roughness, the elimination components machining burr, eliminates the components internal stress, after reducing the heat treatment, the components distort, enhance the components surface to be wear-resisting, <BR>3. and so on bearing ability use in the rotoblast the craft having many, for example: Casting, forging, after the machining, parts list place, after components heat treatment, the <BR>4. sand blasting and so on table place are mainly the manual controls, but the abrade automation and the semiautomatic multi-<BR>5. abrade uses the steel pill and the hard pill are not pills actually in the true sense, said accurately it is the small steel wire or the small steel stick, has after only used period of time, only then looks like likely the meatball, the so-called sand blasting's granulated substance has exposed, is also the river sand, with the structural purpose difference, only has not been the process sieve ratio which the sand blasting uses, are few including the putty, grain size specification. Certainly some professions also have the difference, what like ships profession abrade with what is the genuine steel pill, the sand blasting uses is the metal ore (is not river sand - quartz sand). <BR> supplements again (somewhat repeatedly, some conflicts): the <BR>1. pill and the granulated substance <BR> pill is generally sphere one kind does not have the edges and corners pellet. If the steel wire cuts the pill and so on; the <BR> granulated substance is refers to has the edges and corners sand grains, like brown corundum, white corundum, river sand and so on. <BR>2. spurts with throws <BR> to spurt is spurts by the compressed air as the power the granulated substance material or the pill material the material surface, achieves the elimination and certain roughness. <BR> throws is the pill material by high speed revolving when produces the centrifugal force method, the impact material surface, achieves the elimination and certain roughness.
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