臥式磁性研磨機床(夾具)的設(shè)計【含CAD圖紙+文檔】

壓縮包內(nèi)含有CAD圖紙和說明書,均可直接下載獲得文件，所見所得，電腦查看更方便。Q 197216396 或 11970985 外文資料1：Machining surface quality Mechanical Parts destruction , the general always start from the surface layer. Product performance, in particular its reliability and durability, to a large extent , depends on 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 laws to control the machining process, and ultimately improve the surface quality, enhance product performance goals.I. Effects of surface roughness factor Cutting the influence of surface roughness factor1、 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 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.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.Hardened the surface of the work piece2、 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.3、 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.Surface layer material microstructure changes1、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.1. 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.Surface residual stress1、 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.1、 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 of view. The final surface processes should choose the surface residual compressive stress of processing methods.中文譯文1 機械加工表面質(zhì)量機械零件的破壞，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加工表面質(zhì)量影響的規(guī)律，以便運用這些規(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 刀具相對于工件作進(jìn)給運動時，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，由刀具對金屬的擠壓產(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，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，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。由于磨削加工時所產(chǎn)生的塑性變形和切削熱比刀刃切削時更嚴(yán)重，因而磨削加工后加工表面層上述三項物理機械性能的變化會很大。（1） 、表面層冷作硬化（1） 冷作硬化及其評定參數(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，這些都會使表面層金屬的硬度和強度提高，這種現(xiàn)象稱為冷作硬化。表面層金屬強化的結(jié)果，會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)時間的長短和強化程度的大小。由于金屬在冷作硬化過程中同時受到力和熱的作用，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，對表層金屬的擠壓作用增強，塑性變形加劇，導(dǎo)致冷硬增強。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。切削速度增大，刀具與工件的作用時間縮短，使塑性變形擴展深度減小，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。工件的塑性愈大，冷硬現(xiàn)象就愈嚴(yán)重。a. 、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，表層金屬發(fā)生金相組織的變化，使表層金屬強度和硬度降低，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，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。（2） 、表面層殘余應(yīng)力1、 產(chǎn)生殘余應(yīng)力的原因5、 切削時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。6、 切削加工中，切削區(qū)會有大量的切削熱產(chǎn)生。7、 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，因為最終工序在該工作表面留下的殘余應(yīng)力將直接影響機器零件的使用性能。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，機器零件表面上的局部微觀裂紋，會因拉應(yīng)力的作用使原生裂紋擴大，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。