CK616床頭箱的機(jī)械加工工藝及工裝設(shè)計(jì)-鏜孔夾具含4張CAD圖,ck616,床頭,機(jī)械,加工,工藝,工裝,設(shè)計(jì),鏜孔,夾具,cad 外文資料 Difficult-to-machine material cutting technology Difficult to define the processing of materials and the specific species, the passage of time and different professional areas, for example, commonly used in aerospace industry super heat-resistant alloys, titanium alloys and carbon fiber composite materials are difficult in the field of materials processing. Aerospace industry, engineering and technical personnel to carry out the research and development of processing technology has been developed for use in the field of machine tools and processing methods. In recent years, multi-purpose mechanical products, high functional very strong momentum of development, the requirements necessary to achieve the miniaturization of parts, Micronized. In order to meet these requirements, the materials used must have high hardness, high toughness and high wear resistance, and with these features the processing of materials is particularly difficult, and therefore also difficult for the emergence of new materials. Difficult-to-machine materials such as the development of the times and in different areas of expertise and the emergence of its unique processing technology with the times and fields of research and development and continue to develop. On the other hand, with the advent of information society, it is hard cutting materials technical information can also be exchange via the Internet, therefore, the future of the difficult-to-machine materials such as cutting data will be even more substantial information, processing efficiency is bound to further enhance the In this paper, a difficult-to-machine material cutting at the core, to introduce the technology developments in recent years. In the field of difficult cutting materials In machining, the tool wear occurs normally include the following two forms: (1) arising as a result of mechanical action of wear and tear, such as the collapse edge or abrasive wear, etc.; (2) due to thermal and chemical effects arising from wear and tear, such as bonding, diffusion, corrosion and other wear and tear, as well as cutting edge by the softening, melting and breaking generated, thermal fatigue, thermal cracking and so on. When cutting hard materials, in a very short period of time that the above-mentioned tool wear, which was caused by the processing of materials that exist in more factors to tool wear. For example, the most difficult-to-machine materials are characterized by relatively low thermal conductivity, heat generated when cutting difficult-proliferation, resulting in a high temperature a sharp-edged cutting tools, cutting-edge effects of the apparent heat. This tool will affect the outcome of the binder material at a high temperature drop in bond strength, WC (WC) particles, such as easy to separate, in order to speed up the tool wear. In addition, the difficult-to-machine materials composition and tool material certain components in the cutting reaction under high temperature conditions, analysis of there into, off, or to generate other compounds, which will speed up the formation of edge collapse phenomenon, such as tool wear. In the cutting of high hardness, high toughness is processed materials, cutting edge high temperature, will also appear and when cutting hard materials similar tool wear. Such as high hardness steel cutting and cutting of steel compared to the general, a greater cutting force, tool less than rigid blade, such as would give rise to the phenomenon of collapsing, so that tool life unstable and will shorten the tool life, especially the processing of the workpiece to generate a short chip materials ,wear crescent depression will be produced in the vicinity of cutting edge that the tool breakage often occur in a short period of time. Ultra-heat-resistant alloys in the cutting, because of the high-temperature materials high hardness, cutting a lot of stress on the blade tip, which would have resulted in plastic deformation of cutting edge; At the same time, as a result of hardening the border wear and tear caused by more serious. As a result of these characteristics, it requires users to cut hard materials must be carefully chosen varieties of cutting tools and cutting conditions in order to obtain the desired processing results. The tool shape of cutting Difficult-to-machine material In cutting difficult-to-machine materials, the best shape of the tool can give full play to the performance of tool materials. Materials selection and processing difficult to adapt the characteristics of the anterior horn, posterior horn, into the angle of cutting tool geometry and appropriate to deal with a sharp edge, to improve the accuracy and extended cutting tool life have a great impact, therefore, must respect the shape of the tool not be taken lightly. However, with the promotion of high-speed milling technology applications, has recently been the gradual introduction of small depth of cut so as to reduce the cutting load and to increase the use of inverse milling feed rate, and hence to the shape of cutting edge design ideas have changed. Processing of difficult materials when drilling and increase drilling monoceras, grinding to a cross, is to reduce the torque and an effective way of cutting heat, which can be cut with the cutting surface of the contact area to a minimum range, This extended cutting tool life and improve the conditions of very favorable. Bit in the drilling, the cutting heat can easily stay in the vicinity of the cutting edge, but it is very difficult for Chip in cutting difficult-to-machining materials, the more prominent of these issues, we must give adequate attention to. In order to facilitate Chip, usually in the back has a bit of cutting edge liquid cooling vents may be adequate supply of water-soluble cooling liquid mist cooling agent, so that Chip has become more smooth, on the cutting edge in this way the cooling effect is also very satisfactory. In recent years, has developed some good lubrication properties of the coating material, the material coating the surface of the drill, the use of its processing of the 3 ~ 5D shallow holes, dry drilling methods available. The finishing hole has always been the way the use of boring, but recently has been gradually cut from the traditional approach of continuous change for the introduction of such intermittent cutting contour cutting approach that Chip to improve performance and extend tool life are more favorable. Therefore, this intermittent cutting tool used in the design of boring out immediately after the auto parts are used in the CNC machining. Processing in the screw holes, is also cutting the use of helical interpolation method used for cutting thread milling cutter has a large number of the market. As mentioned above, such a cutting from the original for the conversion to the intermittent cutting, CNC cutting with the understanding of the deepening carried out, this is a gradual process. The use of such cutting means cutting hard materials, they can maintain the smooth cutting of, and conducive to extend the tool life. Difficult cutting conditions for materials processing Difficult cutting conditions for materials processing has always been set lower than that with the improvement of tool performance, high-speed high-precision CNC machine tools, as well as the introduction of high-speed milling and other methods, at present, difficult process of cutting material has entered the high-speed machining, tool period of long-lived. Now, using a small depth of cut so as to reduce the load of cutting edge tool, which can increase the cutting speed and feed rate of processing has become difficult to cut the best way of processing materials. Of course, the choice difficult to adapt to the unique properties of materials processing tool material and tool geometry is also very important, and should seek the best tool of the cutting trajectory. For example, when drilling stainless steel and other materials, due to low thermal conductivity material, it is necessary to prevent a large number remain in the cutting heat on the cutting edge, for which the use of intermittent cutting as far as possible in order to avoid cutting edge and cutting surface friction heat, which will help to extend cutting tool life and ensure stability. With ball-end cutter machining of hard rough material, the tool should be very good shape and with the fixture, so that part can improve the cutting tool before the vibration clamping accuracy and rigidity, so that under conditions of high-speed rotation to ensure that each tooth feed rate to the maximum, but also to extend the tool life.  中文譯文 難加工材料的切削加工技術(shù) 難加工材料的界定及具體品種，隨時(shí)代及專業(yè)領(lǐng)域而各有不同，例如，宇航產(chǎn)業(yè)常用的超耐熱合金、鈦合金及含有碳纖維的復(fù)合材料等，都是該領(lǐng)域的難加工材料。宇航業(yè)的工程技術(shù)人員開展了加工技術(shù)的研究與開發(fā)工作，已經(jīng)研究出適合該領(lǐng)域使用的切削工具和加工方法。近年來，機(jī)械制品多功能、高功能化的發(fā)展勢(shì)頭十分強(qiáng)勁，要求零件必須實(shí)現(xiàn)小型化、微細(xì)化。為了滿足這些要求，則所用材料必須具有高硬度、高韌性和高耐磨性，而具有這些特性的材料其加工難度也特別大，因此又出現(xiàn)了新的難加工材料。難加工材料就是這樣隨著時(shí)代的發(fā)展及專業(yè)領(lǐng)域的不同而出現(xiàn)，其特有的加工技術(shù)也隨著時(shí)代及各專業(yè)領(lǐng)域的研究開發(fā)而不斷向前發(fā)展。 另一方面，隨著信息化社會(huì)的到來，難加工材料切削技術(shù)信息也可通過因特網(wǎng)互相交流，因此，今后有關(guān)難加工材料切削加工的數(shù)據(jù)等信息將會(huì)更加充實(shí)，加工效率也必然會(huì)進(jìn)一步提高，本文以難加工材料的切削加工為核心，介紹該技術(shù)近年來的發(fā)展動(dòng)向。 切削領(lǐng)域中的難加工材料 在切削加工中，通常出現(xiàn)的刀具磨損包括如下兩種形態(tài)：(1)由于機(jī)械作用而出現(xiàn)的磨損，如崩刃或磨粒磨損等；(2)由于熱及化學(xué)作用而出現(xiàn)的磨損，如粘結(jié)、擴(kuò)散、腐蝕等磨損，以及由切削刃軟化、溶融而產(chǎn)生的破斷、熱疲勞、熱龜裂等。 切削難加工材料時(shí)，在很短時(shí)間內(nèi)即出現(xiàn)上述刀具磨損，這是由于被加工材料中存在較多促使刀具磨損的因素。例如，多數(shù)難加工材料均具有熱傳導(dǎo)率較低的特點(diǎn)，切削時(shí)產(chǎn)生的熱量很難擴(kuò)散，致使刀具刃尖溫度很高，切削刃受熱影響極為明顯。這種影響的結(jié)果會(huì)使刀具材料中的粘結(jié)劑在高溫下粘結(jié)強(qiáng)度下降，WC(碳化鎢)等粒子易于分離出去，從而加速了刀具磨損。另外，難加工材料中的成分和刀具材料中的某些成分在切削高溫條件下產(chǎn)生反應(yīng)，出現(xiàn)成分析出、脫落，或生成其他化合物，這將加速形成崩刃等刀具磨損現(xiàn)象。 在切削高硬度、高韌性被加工材料時(shí)，切削刃的溫度很高，也會(huì)出現(xiàn)與切削難加工材料時(shí)類似的刀具磨損。如切削高硬度鋼時(shí)，與切削一般鋼材相比，切削力更大，刀具剛性不足將會(huì)引起崩刃等現(xiàn)象，使刀具壽命不穩(wěn)定，而且會(huì)縮短刀具壽命，尤其是加工生成短切屑的工件材料時(shí)，會(huì)在切削刃附近產(chǎn)生月牙洼磨損，往往在短時(shí)間內(nèi)即出現(xiàn)刀具破損。 在切削超耐熱合金時(shí)，由于材料的高溫硬度很高，切削時(shí)的應(yīng)力大量集中在刃尖處，這將導(dǎo)致切削刃產(chǎn)生塑性變形；同時(shí)，由于加工硬化而引起的邊界磨損也比較嚴(yán)重。 由于這些特點(diǎn)，所以要求用戶在切削難加工材料時(shí)，必須慎重選擇刀具品種和切削條件，以獲得理想的加工效果。 切削難加工材料的刀具形狀 在切削難加工材料時(shí)，刀具形狀的最佳化可充分發(fā)揮刀具材料的性能。選擇與難加工材料特點(diǎn)相適應(yīng)的前角、后角、切入角等刀具幾何形狀和對(duì)刃尖進(jìn)行適當(dāng)處理，對(duì)提高切削精度和延長刀具壽命有很大的影響，因此，在刀具形狀方面決不能掉以輕心。但是，隨著高速銑削技術(shù)的推廣應(yīng)用，近來已逐漸采用小切深以減輕刀齒負(fù)荷，采用逆銑并提高進(jìn)給速度，因此，對(duì)切削刃形狀的設(shè)計(jì)思路也有所改變。 對(duì)難加工材料進(jìn)行鉆削加工時(shí)，增大鉆尖角，進(jìn)行十字形修磨，是降低扭矩和切削熱的有效途徑，它可將切削與切削面的接觸面積控制在最小范圍之內(nèi)，這對(duì)延長刀具壽命和提高切削條件十分有利。鉆頭在鉆孔加工時(shí)，切削熱極易滯留在切削刃附近，而且排屑也很困難，在切削難加工材料時(shí)，這些問題更為突出，必須給以足夠的關(guān)注。 為了便于排屑，通常在鉆頭切削刃后側(cè)設(shè)有冷卻液噴出口，可供給充足的水溶性冷卻液或霧狀冷卻劑等，使排屑變得更為順暢，這種方式對(duì)切削刃的冷卻效果也很理想。近年來，已開發(fā)出一些潤滑性能良好的涂層物質(zhì)，這些物質(zhì)涂鍍?cè)阢@頭表面后，用其加工3～5D的淺孔時(shí)，可采用干式鉆削方式。 孔的精加工歷來采用鏜削方式，不過近來已逐漸由傳統(tǒng)的連續(xù)切削方式改變?yōu)椴捎玫雀呔€切削這類間斷切削方式，這種方式對(duì)提高排屑性能和延長工具壽命均更為有利。因此，這種間斷切削用的鏜削刀具設(shè)計(jì)出來后，立即被應(yīng)用于汽車零件的CNC切削加工。在螺紋孔加工方面，目前也采用螺旋切削插補(bǔ)方式，切螺紋用的立銑刀已大量投放市場。 如上所述，這種由原來連續(xù)切削向間斷切削的轉(zhuǎn)換，是隨著對(duì)CNC切削理解的加深而進(jìn)行的，這是一個(gè)漸進(jìn)的過程。采用此種切削方式切削難加工材料時(shí)，可保持切削的平穩(wěn)性，且有利于延長工具壽命。 難加工材料的切削條件 難加工材料的切削條件歷來都設(shè)定得比較低，隨著刀具性能的提高，高速高精度CNC機(jī)床的出現(xiàn)，以及高速銑削方式的引進(jìn)等，目前，難加工材料的切削已進(jìn)入高速加工、刀具長壽命化的時(shí)期。 現(xiàn)在，采用小切深以減輕刀具切削刃負(fù)荷，從而可提高切削速度和進(jìn)給速度的加工方式，已成為切削難加工材料的最佳方式。當(dāng)然，選擇適應(yīng)難加工材料特有性能的刀具材料和刀具幾何形狀也極為重要，而且應(yīng)力求刀具切削軌跡的最佳化。例如，鉆削不銹鋼等材料時(shí)，由于材料熱傳導(dǎo)率很低，因此，必須防止切削熱大量滯留在切削刃上，為此應(yīng)盡可能采用間斷切削，以避免切削刃和切削面摩擦生熱，這將有助于延長工具壽命和保證切削的穩(wěn)定。用球頭立銑刀對(duì)難加工材料進(jìn)行粗加工時(shí)，工具形狀和夾具應(yīng)很好配合，這樣可提高刀具切削部分的振擺精度和夾持剛性，以便在高速回轉(zhuǎn)條件下，保證將每齒進(jìn)給量提高到最大限度，同時(shí)也可延長工具壽命。