Soft qualitative brittleness and the organic crystal treatment of low melting point

Keywords: 　 of Polishing of Grinding 　 of Organic Crystal 　 in recent years, organic crystal material with its than inorganic crystal more of actor nonlinear optical property and low unripe long cost and more and more be taken seriously. Because have bigger nonlinear coefficient, tall fight scathing threshold value, fast noise to answer time and facilitating element design, the crucial material that organic crystal material is expected to make prospective photoelectron parts of an apparatus or appliance and get applied extensively. However, current organic crystal is mostly qualitative soft, sex is fragile and melting point is very low, treatment is more difficult, affected application consequently. The article with organic nonlinear ketone of 2 benzene armour is optical crystal object, discussed on the foundation of the experiment soft qualitative, brittleness and low melting point is the cut of organic crystal, abrade with polishing method. Ketone of 2 benzene armour (Benzophenone) calls benzene acyl ketone again, its structural formula is C13H10O, have sweet rose flavour, not dissolve at water, the organic dissolvent such as easy dissolve Yu Chun, aether, acetone, benzene. Basically use in organic synthesis and medical industry normally, yi Ke serves as a kind of flavor. Its written guarantee crystal often presses next having in normal temperature two kinds of brilliant, among them α melting point is 48. 1 ℃ , density is 1. 146 G/cm3, β melting point is 26 ℃ , density is 1.

108 G/cm3. The crystal that the article involves all is α model, belonging to orthogonal brilliant is, the space nods group of accord with to be P21P21P21, brilliant afterbirth constant is respectively: A0 ＝ 1.

030 Nm, b0=1.

210 Nm, c0=0.

804 Nm, by northwest industry university crystal of key laboratory of caky technology state grows room use super-cooling fuse-element law to grow. The cut cut of 1 crystal is the first pace that crystal machines. The sort of existing crystal is very much, aviation science foundation funds a project. Function each different, accordingly cut method also differs because of its function difference. Normally, horniness crystal uses phone the fretsaw outside plating diamond piece cut; The crystal with hardness is medium and very high value uses phone the fretsaw inside plating diamond piece cut; To the crystal with perfect cleavage, appropriate is used divide the cut that crack a law; Water-solubility crystal (be like salt crystal) cut of law of commonly used waterline; Ultrathin crystal chip must use chemical cut technology. In addition, still cut of supersonic line patterning method, milling, Laser Cutting waits. Apparent, what what introduce in existing document data is qualitative the cut method of crystal of soft, brittleness, the object is NaCl more, the crystal such as KDP, the mechanical intensity of these crystal should compare crystal of ketone of 2 benzene armour to be gotten greatly much, consequently the method of place introduction does not suit ketone of 2 benzene armour the cut of a kind of organic crystal. In other words, up to now, have not see the cut method that concerns this kind of crystal introduces. We discover, the organic crystal such as ketone of 2 benzene armour pledges as a result of its soft, sex is fragile and melting point is low, use normally mechanical method cut often causes crystal disintegrate. The experiment makes clear, the waterline patterning method of low speed is an efficient way, its characteristic is the temperature gradient that cut process won't bring ministry of mechanical stress standoff, the blast that won't cause crystal consequently is cracked or cleavage, also won't cause the destruction of optical uniformity because of leftover stress. As a result of organic crystal not dissolve at water Yi Rong at organic dissolvent, appropriate organic dissolvent can be used when cut (like alcohol) replace water, the success of facilitating cut. Of the abrade crystal of 2 crystal abrade it is the indispensable link in crystal treatment process, it to crystal figuration, shorten the polishing time, quality that improves a treatment crystal is very important. Abrade abrasive and grind provided choice to answer in order to improve abrade efficiency, and won't give crystal abrade appearance cause too big damage to be a principle. The abrade model that chooses right stuff and open groove to solve crystal effectively to machine easy disintegrate appropriately, drop arris, cleavage to flake wait for a problem. In addition, because organic crystal is right response of difference in temperature is sensitive, easy craze, the environment that opposite constant temperature maintains in abrade process consequently is very important. The abrasive that chooses in the experiment has M of SiO2(40 μ , m) of 28 μ , m) of Al2O3(20 μ , m) of Cr2O3(4 μ , red cast pink (Fe2O3) , fluid of in suspension of 2 oxidation silicon, fluid of oxidation cerium polish. Place is vitreous millstones with millstones. Abrade operation: Put vitreous millstones smooth, go up abrasive a few, drip cool boiled water (room temperature) , the face that requires crystal place treatment again is put on abrasive, press crystal gently with handle gently, slow and mobile. Accomplish as far as possible in abrade process light, slow. Light, it is a consideration brilliant constitution is soft and fragile, if get power too big, add suffer force to all do not make very easily crystal craze; Slow, it is a consideration crystal melting point is low, particularly sensitive to difference in temperature, if shift is too rapid, heat of easy generation attrition causes crystal hot tearing or make abrasive built-in crystal, these go against crystal treatment. Because crystal is qualitative soft and fragile, impose rigidity of abrade phase abrasive bigger, how long can general have more than is needed achieve the optimal treatment result that uses abrasive. Rinse treatment face with clear water and observe crystal surface (range estimation or with microscope observation) , if its surface is rough degree is even and already comparatived with the size that wears bead, replacement finer abrasive undertakes abrade, particular operation requirement and the first process are same. The in machining a process existence of optical material destroys a problem. Destroy a cent to be the surface concave and convex layer and crackle layer two parts, concave and convex layer is the rough layer that the surface after showing the spare parts is machined has lesser span and tiny peak grain, this one but all sorts of instruments measure have the aid of directly piece; Crackle layer is in concave and convex layer under, it is optical material arises because of physico-chemical element to cannot measure a layer subtly directly. In the discovery in practice, want to concave and convex layer exists to have crackle layer surely only, and crackle layer does not have concave and convex layer certainly however, and crackle layer should be gotten greatly than concave and convex layer much. Because crystal of ketone of 2 benzene armour is qualitative soft, sex is fragile, because this is in what what produce in abrade process to destroy a layer especially crackle layer is bigger than general and optical material much, and grind bead to jump over havoc layer normally deeper also. This not only bring difficulty to follow-up treatment, return the optical quality that can affect crystal, cause crystal craze even. Accordingly, when crystal when the surface is very not rough, should be in choose granuality at the beginning the abrasive with fine, inferior hardness is advisable. Discovery is returned in abrade process, crystal is drossy the meeting is jumbly in abrasive, the surface of crystal of drossy meeting cut with rougher granuality of wh some of which. Have considering ketone of 2 benzene armour not dissolve at water Yi Rong the characteristic at organic dissolvent, reason experiment replaces water to undertake with alcohol solution abrade, such but alcohol of have the aid of grain drossy and rapid dissolve and take away; Because alcohol is easy,volatilize at the same time, can walk along attrition tropics. The result makes clear, this one practice can improve treatment efficiency greatly, but also brought a few issues at the same time: Because destroy the existence of the layer,be like, can make interior of crystal of infiltration of alcohol edge micro-crack causes crackle to increase; Solution of alcohol of ketone of 2 benzene armour forms crystallization in crystal surface, the change that causes crystal surface structure. Accordingly, how to perfect an operation after alcohol introduces in machining a process, avoid undesirable effect, still remain to study further. The makes pair of Yu Jing system polish of model of the choice of the polishing polish pink of 3 crystal, polish is very important. The granuality of polishing pink, hardness is the main factor that affects polishing result. Different crystal should use different polishing pink ability to obtain ideal surface roughness. The choice should notice when polishing model, when hardness is exorbitant, the optical face that gets high quality very hard; When hardness is too low, although exterior surface roughness has improvement, sex of Dan Jicheng form, parallelism becomes poor, make crystal surface easy the problem such as occurrence aperture. Polishing process and other crystal are similar, also divide for thick cast and essence of life casts two phase. Thick cast: Operation method and abrade likeness, powder of a few polish pours on flannelette polish model, drip water or rare alcohol, will abrade good crystal appearance is put on polishing pink slow shift. Polishing process requires meticulous, patience. Notable is, it is better that rare alcohol effect is used in polishing process, with thick alcohol pure even alcohol comes polishing can make optical face quality drops. Because at this moment abrasive is particularly fine, grind the grain below to also decrease greatly, the brilliant face certainly will in be in alcohol environment gets of alcohol erode, add crystal to suffer everywhere erode degree endless and identical, its will cause crystal to machine as a result a lot of small hole appear on the face, affect polishing result badly. And right amount alcohol can dissolve already grind the grain below to won't destroy crystal to machine a face again. Essence of life casts: Face of treatment of range estimation crystal is flowing, in glance gender, pervious to light the gender is better and when whole treatment face does not have apparent nick, can undertake essence of life is cast. The method with experiment useful and different process made an attempt. Cast with flannelette essence first: Stick flannelette it is on vitreous board, drop sail upstream, will pass again thick the crystal that cast makes the same score superpose, press gently with handle gently, slow and mobile. Polishing discovers after period of time, treatment face surface roughness is improved somewhat, but the surface appears a lot of subtle nick. Convert after pledget is soggy cast to crystal essence, the effect is good much. Think via the analysis, the fiber of flannelette passes treatment, thicker and hard, and the fiber of pledget comes loose, fine and soft, nature is more appropriate for this softer to processing quality of a material crystal. The discovery in the experiment, the former brilliant side that the surface of crystal of ketone of 2 benzene armour that has machined gives as growing is same, no matter be park air in the clean still water in medium, airtight container all irretentive long, its surface can change very quickly " wool " . Investigate its reason, because ketone of 2 benzene armour has,basically be bigger volatile, cause the appearance thick change. Accordingly, this kind although not easy deliquescence, but have stronger volatile organic crystal surface, must some kind of overburden protects ability to offer use actually. CNC Milling CNC Machining