臥式磁性研磨機(jī)床的夾具設(shè)計(jì)含6張CAD圖
臥式磁性研磨機(jī)床的夾具設(shè)計(jì)含6張CAD圖,臥式,磁性,研磨,機(jī)床,夾具,設(shè)計(jì),cad
附錄1
外文資料1：
Machining surface quality
Mechanical Parts destruction , the general always start from the surface layer of quality. Surface quality research purpose is to master various technological factors on the surface quality of the law, for the use of these layer. Product performance, in particular its reliability and durability, to a large extent , depends on the surface laws to control the machining process,and ultimately improve the surface quality, enhance product performance goals.
一．Effects of surface roughness factor
（一）Cutting the influence of surface roughness factor
1.Tool geometry Reproducibility
Tool relative to the work piece for Feed Movement, in the surface layer leaving a residue cutting area, its shape when the cutter geometry Reproducibility. Reduced feed rate, the main angle, and vice angle increases Corner Radius, may reduce residual height. In addition, the increase appropriate tool in the past to reduce the cutting of plastic deformation, reasonable choice lubricant and improve the quality of grinding tool to reduce the cutting of plastic deformation and inhibit tumor knife and stabbed the production scales, Surface roughness is reduced value of the effective measures.
2.The nature of the work of piece material
Plastic materials processing, from knives to metal extrusion produced plastic deformation. Moreover, chip tool and work piece forced separation of tear, the surface roughness values increase. Work piece material toughness better, the plastic deformation of metals bigger, and the rougher surface. Processing of brittle materials, his chip was broken granular; as chip and the collapse of the broken surface left many Mas, roughen the surface.
3.Cutting dosage
（二）Grinding effects of surface roughness factor
As machining surface toughness when the formation process, grinding the surface roughness also formed by the geometry factors and plastic deformation of metals to decide. Grinding surface roughness effects of the main factors: the size wheel, wheel of hardness, Grinding Wheels, Grinding radial velocity grinding feed mill volume and the number of light, the work piece circumference feed rate and axial feed rate, cooling lubricant.
二．The impact of the surface layer of the physical and mechanical properties of factors
In machining, cutting force due to the work piece and cutting hot, so that the surface layer of metal physical properties have changed, the most important change is the surface layer of metal micro hardness changes microstructure changes and the emergence of residual stress. As grinding as the plastic deformation and thermal cutting edge than the more serious cutting, thus grinding the surface layer above the physical mechanical properties of three changes to be very high.
（一）Hardened the surface of the work piece
1.The hammer-harden and its evaluates the parameter
The process of cutting force role for the plastic deformation, so that the lattice distortion, distortion, the grain between the shear slip. Grain elongated and fibrosis, or even broken, which will make the surface layer of metal hardness and strength. This phenomenon known as cold-hardening. Surface layer metal reinforcing findings will increase resistance to deformation of the metal, reducing the metal plastic. Metal of the physical nature will also change. Cold work sclerosis by the metal-at the high-energy state of instability, only one possible,.Metal instability it is necessary to the relatively stable state of transformation, a phenomenon known as dilution . Weakening the role of the size depends on the level of temperature, duration of temperature and the length of the degree of strengthening. As the metal in the process, and also by the heat, and therefore, after processing the metal surface depends on the final nature of strengthening and weakening of the combined results.
2、 The impact of the cold-hardening main factors
Cutting edge radius increased, the surface of the metal compression increased, exacerbated plastic deformation, resulting in enhanced Chilled. Tool flank wear increased flank with the processing of surface friction intensified, plastic deformation increased, resulting in enhanced Chilled. Cutting speed increases, tool and work piece role shorten the time so that the plastic deformation expand the depth decreases, Chilled depth decreases. Cutting speed increases, cutting heat in the surface layer of shortening the time for music, Chilled level will increase. Feed rate increases, cutting force also increased, the surface of the plastic deformation of metal intensified, Chilled greater role. Work piece material greater plasticity, the more serious Chilled phenomenon.
（二）Surface layer material microstructure changes
1.Grinding burn
When grinding the surface layer temperature phase transition temperature above, the occurrence of metal surface microstructure changes, metal surface so that the strength and hardness reduction, and associated with the residual stress generated, or even micro-crack. This phenomenon known as grinding burn. In the grinding hardened steel, the following three possible burn: tempering burns, burns quenching, annealing burns.
2.Improving ways of grinding burn
Grinding heat caused grinding burn is the root cause, it improved from grinding burn two ways: First, as far as possible to reduce the grinding heat generated; Second is to improve the cooling conditions as possible, to produce less heat into the work piece.
（三）Surface residual stress
1.The residual stress generated reasons
（1）Cutting the surface layer of metal with plastic deformation.The metal surface hematocrit increased only because of the plastic deformation on the surface of metal , while the metal surface of the hematocrit increases, volume expansion, we will inevitably be linked with it by the metal layer prevents, so on the surface of the metal layer of residual stress and the metal layer have residual tensile stress.
（2）Machining, cutting area there will be a lot of cutting heat generated;
（3） Different organizations have different optical density, also have different hematocrit.
If the surface layer of metal produced changes in the microstructure, hematocrit metal surface changes will inevitably be linked with the base metal obstacles, which will have a residual stress.
2.The main components work surface machining processes ultimate method of choice.
Parts final major work surface machining processes essential method of choice, for at the end of the working processes left by the surface residual stress will have a direct impact on the use of machine parts performance. Choose parts final major work surface machining processes, shall consider the main parts of the surface of specific working conditions and possible failure modes. AC load ,machine parts on the surface of the local micro-cracks because of the role of stress so that the original crack expanded, finally led to parts fracture. Improve resistance from parts of fatigue damage point o view. The final surface processes should choose the surface residual compressive stress of processing methods.
中文譯文1
機(jī)械加工表面質(zhì)量
機(jī)械零件的破壞，一般是從表面層開始的。產(chǎn)品的性能，尤其是它的可靠性和耐久性，在很大程度上取決于零件表面層的質(zhì)量。研究表面質(zhì)量的目的就是為了掌握中各種工藝因素對(duì)加工表面質(zhì)量影響的規(guī)律，以便運(yùn)用這些規(guī)律來控制加工過程，最終達(dá)到改善表面質(zhì)量、提高產(chǎn)品使用性能的目的。
1、 影響表面粗糙度的因素
（1） 切削加工影響表面粗糙度的因素
1、刀具幾何形狀的反映
刀具相對(duì)于工件作進(jìn)給運(yùn)動(dòng)時(shí)，在加工表面留下了切削層殘留面積，其形狀是刀具幾何形狀的反映。減小進(jìn)給量、主偏角、副偏角及增大刀尖圓弧半徑，均可減小殘留面積的高度。此外，適當(dāng)增大刀具的前角以減小切削時(shí)的塑性變形程度，合理選擇潤滑液和提高刀具刃磨質(zhì)量以減小切削時(shí)的塑性變形和抑制刀瘤、鱗刺的生成，也是減小表面粗糙度的值的有效選擇。
2、工件材料的性質(zhì)
加工塑性材料時(shí)，由刀具對(duì)金屬的擠壓產(chǎn)生了塑性變形，加之刀具迫使切屑與工件分離的撕裂作用，使表面粗糙度值加大。工件材料韌性愈好，金屬的塑性變形愈大，加工表面就愈加粗糙。加工脆性材料時(shí)，其切屑呈碎粒狀，由于切屑的崩碎而在加工表面留下許多麻點(diǎn)，使表面粗糙。
（2） 磨削加工影響表面粗糙度的因素
正像切屑加工時(shí)表面粗糙度的形成過程一樣，磨削加工表面粗糙度的形成也是由幾何因素和表面金屬的塑性變形來決定的。影響磨削表面粗糙度的主要因素有：砂輪的粒度、砂輪的硬度、砂輪的修整、磨削速度、磨削徑向進(jìn)給量與光磨次數(shù)、工件圓周進(jìn)給速度與軸向進(jìn)給量、冷卻潤滑液。
2、 影響加工表面層物理機(jī)械性能的因素
在切削加工中，工件由于受到切削力和切削熱的作用，使表面層金屬的物理機(jī)械性能產(chǎn)生變化，最主要的變化是表面層金屬顯微硬度的變化、金相組織的變化和殘余應(yīng)力的產(chǎn)生。由于磨削加工時(shí)所產(chǎn)生的塑性變形和切削熱比刀刃切削時(shí)更嚴(yán)重，因而磨削加工后加工表面層上述三項(xiàng)物理機(jī)械性能的變化會(huì)很大。
（一）表面層冷作硬化
1、冷作硬化及其評(píng)定參數(shù)
過程中因切削力作用產(chǎn)生的塑性變形，使晶格扭曲、畸變，晶粒間產(chǎn)生剪切滑移，晶粒被拉長和纖維化，甚至破碎，這些都會(huì)使表面層金屬的硬度和強(qiáng)度提高，這種現(xiàn)象稱為冷作硬化。表面層金屬強(qiáng)化的結(jié)果，會(huì)增大金屬變形的阻力，減小金屬的塑性，金屬的物理性質(zhì)也會(huì)發(fā)生變化。被冷作硬化的金屬處于高能位的不穩(wěn)定狀態(tài)，只要有可能，金屬的不穩(wěn)定狀態(tài)就要向比較穩(wěn)定的狀態(tài)轉(zhuǎn)化，這種現(xiàn)象稱為弱化。弱化作用的大小取決于穩(wěn)定的高低、溫度持續(xù)時(shí)間的長短和強(qiáng)化程度的大小。由于金屬在冷作硬化過程中同時(shí)受到力和熱的作用，因此，加工后表層金屬的最后性質(zhì)取決于強(qiáng)化和弱化的綜合作用結(jié)果。
2、影響冷作硬化的主要因素
切屑刃鈍圓半徑增大，對(duì)表層金屬的擠壓作用增強(qiáng)，塑性變形加劇，導(dǎo)致冷硬增強(qiáng)。刀具后刀面磨損增大，后刀面與被加工表面的摩擦加劇，塑性變形增大，導(dǎo)致冷硬增強(qiáng)。切削速度增大，刀具與工件的作用時(shí)間縮短，使塑性變形擴(kuò)展深度減小，冷硬層深度減小。切削速度增大后，切削熱在工件表面層的作用時(shí)間也縮短了，將使冷硬程度增加。進(jìn)給量增大，切削力也增大，表層金屬的塑性變形加劇，冷硬作用加強(qiáng)。工件的塑性愈大，冷硬現(xiàn)象就愈嚴(yán)重。
（二）表面層材料金相組織變化
1、 磨削燒傷
當(dāng)被磨工件表面層溫度達(dá)到相變溫度以上時(shí)，表層金屬發(fā)生金相組織的變化，使表層金屬強(qiáng)度和硬度降低，并伴有殘余應(yīng)力產(chǎn)生，甚至出現(xiàn)微觀裂紋，這種現(xiàn)象稱為磨削燒傷。在磨削淬火鋼時(shí)，可能產(chǎn)生以下三種燒傷：回火燒傷、淬火燒傷、退火燒傷。
2、 改善磨削燒傷的途徑
磨削熱是造成磨削燒傷的根源，故改善磨削燒傷有兩個(gè)途徑：一是盡可能地減少磨削熱的產(chǎn)生；二是改善冷卻條件，盡量使產(chǎn)生的熱量少傳入工件。
三、表面層殘余應(yīng)力
（一）產(chǎn)生殘余應(yīng)力的原因
1、切削時(shí)在加工表面金屬層內(nèi)有塑性變形發(fā)生，使表面金屬的比容加大，由于塑性變形只在表層金屬中產(chǎn)生，而表層金屬的比容增大，體積膨脹，不可避免地要受到與它相連的里層金屬的阻止，因此就在表面金屬層產(chǎn)生了殘余應(yīng)力，而在里層金屬中產(chǎn)生殘余拉應(yīng)力。
2、切削加工中，切削區(qū)會(huì)有大量的切削熱產(chǎn)生。
3、不同金相組織具有不同的密度，也具有不同的比容，如果表面層金屬產(chǎn)生了金相組織的變化，表層金屬比容的變化必然要受到與之相連的基體金屬的阻礙，因而就有了殘余應(yīng)力產(chǎn)生。
4、 零件主要工作表面最終工序加工方法的選擇
零件主要工作表面最終工序加工方法的選擇至關(guān)重要，因?yàn)樽罱K工序在該工作表面留下的殘余應(yīng)力將直接影響機(jī)器零件的使用性能。選擇零件主要工作表面最終工序加工方法，須考慮該零件主要工作表面的具體工作條件和可能的破壞形式。在交變載荷作用下，機(jī)器零件表面上的局部微觀裂紋，會(huì)因拉應(yīng)力的作用使原生裂紋擴(kuò)大，最后導(dǎo)致零件斷裂。因此從提高零件抵抗疲勞破壞的角度考慮，該表面最終工序選擇能在該表面產(chǎn)生殘余壓應(yīng)力的加工方法。
附錄2
外文資料2
The magnetic machining technology
Use the magnetic field generated by abrasive grinding pressure magnetic mechanical polishing surface finishing another new technology. Currently, the right components within a round face, cylindrical surface, plane. Molding and so on the surface of the complex shape of small and medium parts of the surface magnetic machining development and research. From the principle of speaking, it can be any geometric shape of the surface of precision finishing. Therefore, there is a broad prospect, will produce good economic and social benefits.
一．The magnetism grind of process principle
Given one pair of poles, between the two poles of a magnetic field formed, full of the energy and intensity generated magnetic induction. If a magnetic filled with both magnetic and has cutting ability of composite mill Magnetic Abrasive, Abrasive grains will closely ,and with the rules and form a "magnetic brush".
Magnetic Abrasive grains in the "magnetic brush", if home work piece, "magnetic brush" will be the magnetic "pressure" in the form of role in the work piece surface. In order to achieve the surface of the work piece machining, work piece also must give way to the campaign--rotation and axial vibration. With the work piece and Magnetic Abrasive grains relative movement between the produce, Magnetic Abrasive grains on the work piece surface rough, and the burr edge, corner are all magnetic induction intensity and the magnetic field lines were concentrated, so they were the first to be processed, to the removal of burrs and surface finishing purposes. Magnetic grinding process, the single abrasive the magnetic field, maintaining the magnetic field strength and tangential to the common role of friction, so abrasive to maintain stability in the process space. Implementation of the work piece surface grinding process. At the same time the processing region external magnetic abrasive grains because of the strength of the magnetic field,will automatically go to the work piece machining regional pool, filling in the pole between the work piece and in the processing, formed a complete and continuous processing.
（一）Abrasive grinding mechanism
In magnetic ground processing, magnetic powder abrasive grain is a grain group, by the magnetic field in magnetic pressure and the role to the work piece surface. Abrasive the force as mentioned above. According to the theory of precision cutting and Moldova rub theory, we can see the magnetic abrasive grinding machining and work piece surface contact sliding rub, squeeze, Characterizations and cutting phenomenon.Thus the magnetic grinding mechanism mainly include the following:
1.Trace Cutting and extrusion;
2.Multiple plastic deformation wear;
3.Corrosion friction and wear;
4.Electrochemical wear;
5.Abrasive Cutting trajectory.
（二）Magnetic lapping processing technologies and advanced innovative
Magnetic abroad grinding technology has been successfully applied in many areas. If the stainless steel cylinder wall net grinding, as amended Super abrasive Grinding Wheel, grinding plastic lens, slender shaft ceramic processing, Bearing in Central and Raceway, hydraulic machinery used lubricating valves, gear pumps, ball valves, stainless steel household utensils, thread roller, Ball Screws, ball bearings Cage, disc brakes.
（三）Magnetic lapping processing technology popularization and application prospects
Magnetic lapping processing technology is constantly in recent years as a research and development of new technologies, mainly for various molding surface, dysphasia surface, small spiral surface and surface trench finishing and removes burrs. The current processing technology has been successfully applied to many hi--tech field, can not only realize remove burrs and improve the surface quality of parts, but only so much of the manual processing of finished parts to achieve automation, reduce the labor intensity, improvements to the working environment, but also substantially increased the productivity, stability, quality of processing. For example :The stainless steel cylinder wall net grinding, convex oval piston surface, within the trench and with the cross-with-the finished surface of demurring, hydraulic components , sewing machines Shaped small parts automobile engine parts, aerospace, medical equipment, electronic components and other mechanical tools various parts of precision machining, to replace the traditional and backward processing techniques and methods to improve the mechanical parts surface quality , resolve the current production of parts is not high surface quality problems.
However, as a magnetic polishing abrasive magnetic abrasive, China is still not in production,its use mainly rely on imports. Magnetic Abrasive Finishing led to the high cost of a serious constraint magnetic lapping processing technology in our application. This magnetic abrasive not only repeated use, import substitution magnetic abrasive, but also because of simple preparation technology , do not need high temperature and high pressure and cooling equipment, energy-saving and environmentally-friendly, low production costs, promote the use of very broad prospects, and is expected to make a good economic and social benefits.
中文譯文2
磁性研磨加工技術(shù)
利用磁場(chǎng)中的磁性磨料所產(chǎn)生的磁磨壓力進(jìn)行磁性研磨加工時(shí)機(jī)械零件表面光整加工的又一新工藝。目前，已對(duì)零件的內(nèi)圓面、外圓面、平面、成形面等表面及幾何形狀復(fù)雜的中小型零件表面進(jìn)行了磁性研磨加工的開發(fā)研究。從原理上講，它可以對(duì)任何幾何形狀的表面進(jìn)行精密光整加工。因此，有著十分廣闊的應(yīng)用前景，必將產(chǎn)生良好的經(jīng)濟(jì)效益和社會(huì)效益。
一、磁性研磨的加工原理
給定一對(duì)磁極，在兩磁極間形成了一個(gè)磁場(chǎng)，就充滿磁能并且產(chǎn)生磁感應(yīng)強(qiáng)度。如果在磁極中填充一種既具有磁性又具有切削能力的復(fù)合磨料——磁性磨料，磨料磨粒將緊密地、有規(guī)則地排列起來，形成“磁刷”。
在磁性磨料磨粒的“磁刷”中，置入被加工工件，“磁刷”產(chǎn)生的磁力將以“壓力”的形式作用于工件表面上。為了實(shí)現(xiàn)對(duì)工件表面的加工，還必須給工件的運(yùn)動(dòng)方式——旋轉(zhuǎn)運(yùn)動(dòng)和軸向運(yùn)動(dòng)。隨著工件與磁性磨料磨粒間相對(duì)運(yùn)動(dòng)的產(chǎn)生，磁性磨料磨粒對(duì)工件表面產(chǎn)生磨削，實(shí)現(xiàn)工件表面的再加工。由于工件表面的粗糙不平處、毛刺以及棱邊、尖角等都是磁感應(yīng)強(qiáng)度大和磁力線幾種的部位，因而這些部位首先得到加工，從而達(dá)到去除毛刺和表面光整加工的目的。磁性研磨過程中，單顆磨粒在磁場(chǎng)作用力、磁場(chǎng)保持力和切向摩擦力的共同作用下，使磨粒穩(wěn)定地保持在加工間隙中，實(shí)現(xiàn)對(duì)工件表面的研磨加工。同時(shí)處在加工區(qū)域外部的磁性磨料磨粒由于受磁場(chǎng)力的作用，將自動(dòng)向工件加工區(qū)域匯集，填充于磁極和工件之間參與加工，形成一個(gè)完整和連續(xù)的加工過程。
二、磨粒的磨削機(jī)理
在磁性研磨加工中，磁性磨料是由微粉磨粒組成的磨粒群，在磁場(chǎng)中受到磁力的作用而壓向工件表面，磨料受力情況如前所述。根據(jù)精密切削理論和摩擦學(xué)理論，可以得知磨粒在磁性研磨加工中與工件表面產(chǎn)生接觸滑擦、擠壓、刻劃和切削等現(xiàn)象。因此磁性研磨的磨削機(jī)理主要包括以下幾方面：
1、微量切削與擠壓作用；
2、多次塑變磨損作用；
3、摩擦腐蝕磨損作用；
4、電化學(xué)磨損作用；
5、磨粒的切削軌跡。
三、磁性研磨加工技術(shù)的創(chuàng)新性與先進(jìn)性
國外的磁性研磨技術(shù)已經(jīng)成功地應(yīng)用在多個(gè)方面。如不銹鋼凈氣瓶的內(nèi)壁研磨，研磨修正超硬磨料砂輪，研磨塑料透鏡，細(xì)長軸類陶瓷加工，軸承環(huán)及內(nèi)外圈滾道，液壓機(jī)械用的滑閥、泵齒輪、球閥，家用不銹鋼器皿，螺紋壓輥，滾珠絲杠，滾動(dòng)軸承保持架，盤形制動(dòng)器。
四、磁性研磨加工技術(shù)的推廣應(yīng)用前景
磁性研磨加工技術(shù)是近年來不斷開發(fā)研究的一種新技術(shù)，主要用于各種成型表面、異型曲面、螺旋表面及細(xì)小溝槽表面進(jìn)行光整加工及去除毛刺。目前這一加工技術(shù)已成功地應(yīng)用于許多高新技術(shù)領(lǐng)域，不僅可以實(shí)現(xiàn)去毛刺、提高零件表面質(zhì)量，而且使許多原來只能用手工加工的零件的精加工實(shí)現(xiàn)自動(dòng)化，簡琴了工人的勞動(dòng)強(qiáng)度，改善了工作環(huán)境，也大幅度提高了生產(chǎn)效率，穩(wěn)定了加工質(zhì)量。例如：不銹鋼凈氣瓶的內(nèi)壁研磨，中凸變橢圓鋁合金活塞表面、帶有內(nèi)溝槽及內(nèi)交叉孔等內(nèi)表面的精加工的去毛刺，液壓元件、縫紉機(jī)異型小零件、汽車發(fā)動(dòng)機(jī)零件、航空航天、醫(yī)療器械、電子元件、各種刀具等機(jī)械零件的精密加工，以取代傳統(tǒng)落后的加工工藝和方法，提高機(jī)械零件的表面質(zhì)量，解決目前生產(chǎn)中零件表面質(zhì)量不高的難題。
然而，作為磁性研磨加工磨具的磁性磨具，目前在我國還不能生產(chǎn)，它的使用主要依靠進(jìn)口，導(dǎo)致磁性研磨加工的成本居高不下，嚴(yán)重制約了磁性研磨加工技術(shù)在我國的推廣應(yīng)用。這種磁性磨具不但可以多次重復(fù)使用，帶頭進(jìn)口磁性磨具，而且，因其制備工藝簡單、不需要高溫高壓和冷卻設(shè)備，因此節(jié)約能源，利于環(huán)保，生產(chǎn)成本低，推廣應(yīng)用前景十分廣闊，并且渴望取得良好的經(jīng)濟(jì)效益和社會(huì)效益。
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