踏板组件的冲压模具设计【含CAD图纸、文档资料】
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踏板
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毕业设计(论文)外文资料翻译设计(论文)题目: 踏板组件(B)冲压模具设计 学生姓名: 学 院: 机械与电气工程学院 专 业: 材料成型及控制工程 班 级: 学 号: 指导教师: 外文出处: 年2月27日1外文资料翻译译文(约3000汉字):模具设计手册伊凡娜苏奇14-8 表面清洁制造的金属零件可能含有润滑剂、车间污垢和灰尘、磨料、材料碎片和大量其他杂质或污染物的残留物。通常,这些零件必须清洁,以便为某些其他精加工过程(如喷漆或其他涂层应用)准备表面。选择合适的清洗方法必须考虑到许多因素。首先,必须确定要清除的脏物或污染物的类型,因为清除油脂所需的表面清洁方法与清除金属碎屑所需的方法不同。必须考虑成品零件的表面要求,要避免损害产品的某些特殊特性。例如,某些金属板五金件的开口不应去毛刺,因为一侧的粗糙度对其安装很重要。此外,在考虑到特定公司或工厂的清洁能力的情况下,必须针对后续的精加工过程对问题进行评估。这有几种零件清洁方法,每种方法使用不同的原理,每种方法适用于不同的清洁应用范围。有些通过机械手段清除要去除的元素;另一些则使用化合物、蒸汽或电解质、超声波、盐浴和其他变化来解决。下面列出了这些清洗过程的主要类别。14-8-1机械清洗机械清洗利用磨料和其他物体的机械作用,用于研磨、抛光、抛光、喷砂清理或喷丸处理等过程。磨料颗粒可以是干燥的,也可以是包含在液体中的,并应用于零件表面。机械清洁中使用的其他物体可以是任何东西,如碎布、玻璃珠或抛光剂。这种清洁方法可用于清除污垢、铁锈、飞边、零件去毛刺或仅用于表面粗加工以进行后续精加工。实际操作程序取决于特定部分和预期结果。振动清洗常用于小型金属冲压件,这些零件与以小石子或类似材料为形式的磨具混合,放置在振动或旋转的大滚筒中。零件和研磨元件的同时移动能够去除毛刺、平滑表面,并在一定程度上精加工边缘和去除其锐度。较大尺寸的零件可以通过一个设备擦洗他们的表面,通过与砂带接触这种研磨方法来去毛刺和表面清洁。喷砂清理使用磨料颗粒,将其推到要清理的零件上。它是一种用于黑色和有色金属锻件和铸件或焊接件等的清洗方法。喷丸与喷砂的不同之处在于,喷丸的清洁作用仅仅是对其提高材料疲劳强度的补充。这种类型的表面处理也能消除否则会产生应力腐蚀开裂的拉伸应力。在喷丸处理中,靠在零件上的物体不是由磨料引起的,它们通过产生大量的浅凹痕来攻击表面,这使得该过程很容易与材料表面的冷加工相媲美。所有的注重尺寸的零件都要用玻璃珠清洁表面。作为一种清洁方法,它优于在液体中使用研磨泥浆。玻璃珠清洁可用于准备喷漆、钎焊、焊接和其他类似的制造工艺。它产生哑光饰面,因此也可用于装饰目的。用玻璃珠清洁的一个决定性的优点是,在清洁表面时,不会去除可测量的尺寸量。14-8-2碱性清洗最常用的工业清洗方法是碱性清洗,其作用基本上是物理和化学的,辅之以表面活性剂、乳化剂、分离剂、皂化剂和润湿剂的组合,所有这些都会清洗部件。溶液可以通过搅拌来加热。可溶解的污垢颗粒被冲走。固体颗粒从零件中分离出来,允许在底部的污泥中沉淀,或通过过滤和类似程序从溶液中漂浮并去除。碱性清洗可用于清除蜡类固体、金属颗粒、油、油脂、灰尘和其他污染物。该工艺的应用是将零件浸泡在液体中或通过喷雾或乳化。这样的清洗过程通常要经过水洗和干燥循环。14-8-3电解清洗该工艺是一种特殊类型的浸没清洗,工艺中包含电极。直流电通过溶液传导,待清洗部分作为阳极,而电极作为阴极。有些工艺交替使用阴极-阳极名称。在清洗周期中,氧气在阳极处的净化作用可能进一步有助于操作。这种类型的清洁可用于除锈、准备磷化、铬酸盐处理、喷漆,特别是电镀,后者要求更高的清洁度。14-8-4乳化液清洗这一过程使用两种基本材料,它们彼此不溶,例如水和油,并结合一种能够迫使它们乳化的乳化剂。这种类型的清洗用于严重污染的零件,通常在循环后进行碱性清洗,以最终去除非常微小的污染物。乳化剂有两种:(1)有助于在水中形成由溶剂组成的乳状液,和(2)有助于在溶剂中形成由水组成的乳液的乳化剂。常用的乳化剂有非离子聚醚、烃磺酸盐、胺皂、胺盐、甘油或多元醇。溶剂通常来源于石油,如环烷烃(煤油)。14-8-5溶剂清洗这种清洗方法包括将溶剂应用于有机污染物,如油或油脂,以试图将它们从零件表面去除。有时,为了去除零件表面的溶剂,这种清洗必须进行碱洗。这种清洗也可用于去除电镀零件上的水。溶剂可以是石油基(如石脑油、矿油或煤油)或氯化烃(三氯甲烷、三氯乙烯、二氯甲烷)或醇(异丙醇、甲醇、乙醇)。其他溶剂包括但不限于苯、丙酮和甲苯。清洁机制主要适用于有机污染物,如油脂或油。这些杂质很容易溶解和去除,或从零件表面冲洗掉。14-8-5-1蒸汽脱脂溶剂蒸汽脱脂是溶剂清洗的一个专业分支。它使用氯化或氟化溶剂去除油脂、蜡或油等杂质。将要脱脂的物体放在一个罐中,在这个罐中有一种溶剂是煮沸的。物体通过蒸汽的作用而脱脂,蒸汽比空气重,从而使后者从油箱容积中排出。到达上部冷却器区域后,这些加热的蒸汽冷凝并滴回到加热的地方。14-8-6酸洗酸洗使用含有有机酸、矿物酸和酸盐的各种溶液,与润湿剂和洗涤剂结合用于钢铁的清洗。这种C倾斜法可以用来除去油、油脂、氧化物和其他污染物,而不需要额外加热。酸浸洗和酸洗是非常相似的工艺,酸浸洗是更积极的处理,用于清除锻件或铸件和各种半成品的氧化皮。无机酸和无机盐很多,它们形成无机(矿物)酸溶液或酸盐溶液或酸溶剂混合物。这些清洗液的有机成分可以是草酸、酒石酸、柠檬酸、乙酸和其他酸,以及酸盐,例如硫酸钠、氟化氢盐或磷酸钠。此过程中使用的溶剂可以是乙二醇或单丁基(和其他)醚。14-8-7酸洗金属材料的酸洗去除了零件表面的氧化物或结垢。它也可用于去除其他污染物,方法是将零件浸入酸的液体溶液中。这种溶液的成分、温度和成分的选择可能不同,最常见的酸洗液是硫酸。在需要镀锌前蚀刻的地方使用盐酸。不锈钢的酸洗采用硝酸-氢氟酸。酸洗的机理是氧化皮穿透裂纹,酸洗液与金属发生化学反应。为了使酸洗液不腐蚀基底金属,加入了以明胶、面粉、胶水、石油污泥等物质形式存在的抑制剂。缓蚀剂可以减少铁表面的损失,减少氢脆的范围,同时保护金属不受点蚀的影响,点蚀可能发生在酸洗过度的地方。14-8-8 盐浴除垢盐浴除垢工艺用于除垢,必须先进行酸洗或酸浸洗才能彻底除垢。盐浴除鳞可分为三类:氧化型、还原型和电解法。该模式甚至可以与前两个过程一起使用。氧化型盐浴除鳞是最常用的除垢方法,因为它的简单性,即使电解法提供更大的除垢能力。还原法的优点是盐浴温度较低。去除的水垢与除鳞盐一起,形成不溶性污泥,必须用机械方法去除。因此,这些杂质可以沉淀在一个平底锅中,然后放在那里收集。14-8-9超声波清洗当超声波能量应用于氯化烃溶剂溶液、水和表面活性剂或任何其他清洁溶液类型时,将促进清洁过程、清除各种污染物。它可用于在材料中去除薄颗粒,或清除复杂部件、贵金属、或封闭单元,并用于清除需要极度清洁的地方。超声波工艺的缺点是成本高,这是因为设备的初始成本和维护成本要高得多。然而,这种类型的清洁被发现是有益的,因为以前只有手工清洁方法。14-9表面涂层选择表面涂层时,应考虑其必须覆盖的基本金属。一些涂层被用作防止磨损、腐蚀、氧化以及许多其他原因的保护。表面涂层在基本金属本身和环境之间形成屏障,有时对其稳定性有害。有涂层可以改变摩擦性能,增强零件的美观性。各种涂层可用于各种应用,但最常用于保护基本金属(基本产品)免受外部影响。即使是组件内的两个金属部件也能够通过形成电偶电池来相互影响,这如果选择不当,基本材料可能对其涂层产生不利的反应。因此,在选择涂层的保护类型和保护量时,必须考虑对形成电偶的可能性的评估。这涉及到涂层的性质是朝其下面的金属阴极还是阳极。例如,即使镍对铁是阴极的,而锌是阳极的,钢也可以通过镍或锌涂层免受其他影响。镍通过成功地阻止外部腐蚀环境对材料的影响来保护钢,为此,这种涂层必须没有气孔。锌比钢更容易腐蚀,而腐蚀性反应的副产物,氧化锌,相当大,损害腐蚀过程并保护涂层材料。许多金属能够形成氧化膜,当其稳定时,作为该特定材料的保护涂层。铝氧化物在酸性环境中生长,在那里形成厚的保护层,但一旦碱性合金阳极氧化,涂层收缩,变薄,坚硬,稳定。一些氧化剂,如锡、锌、钛和其他的氧化剂,可以通过额外的化学或电化学处理来稳定,这将使它们成为基本金属材料的保护层。这种保护的成功取决于对原电池过程的正确分析,在此过程中,阳极溶解的金属必须受到相等和相反的阴极反应的保护。14-9-1电镀电镀过程实际上应该被称为电离,因为它利用电镀零件和电镀材料之间的电偶原理将材料颗粒转移到零件表面。在这一过程中,直流电被施加到金属盐溶液中,在该溶液中沉积待涂覆的零件。这些部分通过连接到能源的负端,承担起阴极或负极的作用。大型部件悬挂在连接电源负极的铜棒上,小部件(如垫圈或螺栓)放置在金属丝篮中。涂层金属本身充当阳极,并以板、棒或挤压形状添加到镀液中。当受电流影响时,阳极金属材料缓慢电离,其粒子进入镀液。这些离子向阴极极化部分移动,在阴极极化部分表面以金属晶体的形式沉积。某些类型的金属涂层工艺要求对涂层浴进行加热,有时添加液体搅拌作用以提高薄膜的均匀性。涂层的发展速度取决于电流强度和镀液温度。如果镀液温度更高或电流的安培数更大,则涂层过程变得更快。但是,如果强度过高或溶液温度过高,涂层会变得粗糙和不充分。电流必须是低电压的(通常几伏就足够了),但强度必须相当高,每平方英尺涂层表面的电流为0.1到2安培或更多。有机化合物有时被添加到镀液中,它们的微量在很大程度上改变了涂层的性能。它们的影响主要是朝向美观的外观,随后对涂层表面进行平滑处理,使其具有光泽。这些严格意义上的光学增强被它们提供的防腐保护减弱所抵消。几乎所有的金属都可以用现代方法和现代技术作为涂层进行电镀。然而,对于一些人来说,这个过程是如此昂贵,以至于它仍然只是一个技术上的好奇心。最常见的四种镀锌工艺是:l酸性电偶涂层,其中金属以阳离子形式存在于简单的盐溶液中,例如硫酸盐、硫酸盐、氟硼酸盐或氯化物的溶液中。该工艺用于镍、铜、锌和锡涂层的应用。l复杂的碱性氰化物浴,带有阴离子形式的金属颗粒,连接到溶液的氰化物部分。这种类型的镀液用于铜、镉、锌、银和金涂层的应用。l复杂酸浴,其中阴极沉积通过中间阶段实现,或作为阴极膜。铬酸就是一个例子,它能形成单重铬酸盐离子。l金属的碱性浴,形成两性氧化物,如锡酸钠浴,含有锡酸钠或锡酸盐,用羟基离子来稳定。2外文资料原文(与课题相关,至少1万印刷符号以上):Handbook of Die DesignIvana Suchy14-8 SURFACE CLEANINGMetal parts, as manufactured, may contain residues of lubric ants, shop dirt and dust, abrasives, splinters of materials, and a host of other impurities or contaminants. Often these parts have to be cleaned in order to prepare the surface for some other finishing process, such as painting or other coating application. The proper cleaning method of such parts must be well chosen, with many factors in mind. First, the type of soil or contaminant to be removed has to be identified, since a different method of surface cleaning is needed for removal of grease than for metal chips. The surface requirements of the finished part must be taken into account in order not to use a method which may become detrimental to some special feature of the product. As an example, openings for certain sheet-metal hardware should not be deburred, as the roughness of one side is important for its installation. Further, the problem has to be assessed with regard to the subsequent finishing processes, while bearing in mind the cleaning capacities of the particular company or plant. There are several methods of parts cleaning, each using a different principle and each being applicable to a different range of cleaning applications. Some attack the elements to be removed by mechanical means; others use chemical compounds or steam or electrolytes or ultrasound, salt baths, and other variations. Main categories of these cleaning processes are listed below.14-8-1 Mechanical CleaningMechanical cleaning utilizes a mechanical action of abrasives and other objects, which are used in processes such as those of grinding, polishing, buffing, blast cleaning, or shot peening. Abrasive particles may be either dry or as contained in a liquid and applied against the surface of the part. Other objects used in mechanical cleaning may be anything from rags up to glass beads or buffing compounds. This type of cleaning method may be used for removal of dirt, rust, flash, for deburring of parts, or just for roughing of the surface for subsequent finishing. The actual procedure depends on the particular part and the expected outcome. Vibration cleaning is frequently used for small metal- stamped parts, where these are mixed with abrasives in the form of small stones or similar materials and placed in large drums, which are either vibrating or rotating. The simultaneous movement of parts and abrasive elements is capable of remov ing burrs, smoothing the surface, and to some degree finishing the edges and removing their sharpness. Larger-sized parts are deburred and surface-cleaned by an abrasive method of running them through an equipment which scrubs their surface by contact with an abrasive belt. Blast cleaning uses abrasive particles, propelling them against the part to be cleaned. It is a cleaning method used with ferrous and nonferrous forgings and castings or to clean weldments, and so on. Shot peening differs from blast peening in that its cleaning action is merely an addition to its actual purpose of improving the fatigue strength of the material. This type of finishing is also capable of relieving tensile stresses that would otherwise produce stress-corrosion cracking. In shot peening, the objects propelled against the part are not of abrasive origin.They attack the surface by creating a multitude of shallow indents, which makes the process easily comparable to cold working of the material surface. Cleaning of the surface with glass beads is used for parts of all sizes. As a cleaning method, it surpasses that using an abrasive slurry within a liquid. Glass bead cleaning may be utilized in preparation for painting, brazing, welding, and other similar manufacturing processes. It produces a matte finish, for which reason it may also be used for decorative purposes. A definitive advantage of cleaning with glass beads is that while the surface is being cleaned, no measurable amount is removed.14-8-2 Alkaline CleaningThe most often used industrial cleaning method is alkaline cleaning, the action of which is basically physical as well as chemical, aided by combinations of surfactants, emulsifiers, separating agents, saponifiers, and wetting agents all attacking the part to be cleaned. The solution may be heated or agitated in motion by stirring. Dissolvable particles of dirt are washed away. Solid particles are separated from the part and allowed to either settle in the fom of sludge to the bottom or be floated away and removed from the solution by means of filtering and similar procedures. Alkaline cleaning may be used for removal of wax-type solids, metallic particles, oil,grease, dust, and other contaminants. The application of the process is by immersion in liquid or by spraying or emulsification. Such a cleaning process is often followed by a water rinse and a drying cycle.14-8-3 Electrolytic CleaningThis process is a specialized type of immersion cleaning, with the inclusion of electrodes within the process. A direct current is conducted through the solution, where the part to be cleaned serves as the anode while the electrode acts as the cathode. Some processes alternate the cathode-anode designation. The cleansing action of oxygen, which develops at the anode during the cleaning cycle, may further aid the operation. This type of cleaning may be used for removal of rust, in preparation for phosphating,chromating, painting, and especially for electroplating, the latter demanding a higher degree of cleanliness.14-8-4 Emulsion CleaningThis process uses two basic materials, insoluble within each other, such as water and oil, combined with an emulsifying agent capable of forcing them to emulsify. This type of cleaning is used with heavily soiled parts, and the cycle is usually followed by alkaline cleaning for final removal of very minute contaminants. Emulsifiers are of two types: (1) emulsifiers that aid the formation of emulsion which consists of a solvent in water, and (2) emulsifiers that aid the formation of emulsion which consists of water in solvent. Frequently used emulsifiers are nonionic polyethers, hydrocarbon sulfonates, amine soaps, amine salts, glycerols, or polyalcohols. Solvents usually are of petroleum origin,such as naphthenic hydrocarbons (kerosene).14-8-5 Solvent CleaningThis cleaning method consists of an application of solvents to the organic contaminants such as oils or grease, in an attempt to remove them from the surface of parts. Sometimes such cleaning has to be followed by an alkaline wash, in order to remove the solvent itself from the part surface. This type of cleaning may also be used for removal of water from electroplated parts. Solvents may be either petroleum-based (such as naphtha, mineral spirits, or kerosene)or chlorinated hydrocarbons (trichloroethane, trichloroethylene, methylene chloride) or alcohols (isopropanol, methanol, ethanol). Other solvents include but are not restricted to benzol, acetone, and toluene. The mechanism of cleaning is applicable mainly to contaminants of organic origin, such as grease or oils. These impurities may be easily solubilized and removed, or washed off the part s surface.14-8-5-1 Vapor Degreasing. Vapor degreasing with solvents is a specialized branch of solvent cleaning. It uses chlorinated or fluorinated solvents for removal of soils such as grease, waxes, or oil. The objects to be degreased are placed within a tank, where a solventis boiled. Objects are degreased by the action of vapors, whichbe ing heavier than airdisplace the latter from the volume of the tank. On reaching the upper cooler zones, these heated vapors condense and drip back down where they are reheated.14-8-6 Acid CleaningAcid cleaning uses various solution containing organic acids, mineral acids, and acid salts,combined with a wetting agent and detergent for cleaning of iron and steel. Such a C leaning method may be used to remove oil, grease, oxide, and other contaminants without additional application of heat.Acid cleaning and acid pickling are quite similar processes, with acid pickling being much more aggressive treatment, used for removal of scale from forgings or castings and from various half- finished mill products. Mineral acids and salts are numerous, forming either inorganic (mineral) acid solutions or solutions of acid salts or acid-solvent mixtures. Organic components of these cleaning solutions may be oxalic, tartaric, citric, acetic, and other acids, with acid salts such as sodium acid sulfate, bifluoride salts, or sodium phosphates. Solvents used in this process may be ethylene glycol or monobutyl (and other) ethers.14-8-7 PicklingPickling of metal materials removes the oxides, or scale, off the surface of parts. It may be used for removal of other contaminants as well, by immersing the parts in a liquid solution of acid. Such a solution may vary in its composition, temperature, and selection of ingredients, the most common pickling bath being sulfuric acid. Hydrochloric acid is utilized where etching prior to galvanizing is needed. For pickling of stainless steel,nitric-hydrofluoric acid is used.The mechanism of pickling is that of a penetration of the scale through the cracks and chemical reaction of the pickling solution with the metal underneath. In order for the pickling solution not to attack the base metal, inhibitors in the form of gelatin, flour, glue, petroleum sludge, and other substances are added. Inhibitors can minimize the loss of iron surface and reduce the range of hydrogen embrittlement while protecting the metal from pitting, which may occur where pickling becomes excessive.14-8-8 Salt Bath DescalingThe salt bath descaling process is used for removal of scale and it must- for a complete removalbe followed by acid pickling or acid cleaning. Salt bath descaling may be divided into three groups: oxidizing type, reducing type, and an electrolytic method. Thelatter may be used even in conjunction with the previous two processes. Oxidizing type of salt bath descaling is the most often used method of scale removal because of its simplicity, even though the electrolytic method offers greater scale-removing capabilities. The reducing methods advantage is lower temperatures of the salt bath. The removed scale, along with the descaling salts, forms an insoluble sludge, which must be taken out mechanically. For that reason such impurities are allowed to settle into a pan placed there for their collection.14-8-9 Ultrasonic CleaningUltrasonic energy, when applied to the solution of chlorinated hydrocarbon solvents or to water and surfactants or to any other type of cleaning solution, will boost the cleaning process, removing various types of contaminants. It may be used for removal of fine particles embedded within the material, or for cleaning of complex parts, precious metals, or sealed units, and also for cleaning where extreme cleanliness is required. The disadvantage of the ultrasonic process is its high cost, which is due to the much higher initial cost of the equipment and its maintenance. However, this type of cleaning has been found beneficial where previously only hand-cleaning methods worked.14-9 SURFACE COATINGSurface coating should be chosen with regard to the application it has to serve, along with a consideration for the basic metal it has to cover. Some coatings are used as a protection against abrasion, corrosion, oxidation, and for a host of other reasons. Surface coating creates a barrier between the basic metal itself and the environment, sometimes detrimental to its stability. There are coatings to alter the frictional properties and to enhance the an aesthetic appeal of the part. V arious coatings may be used for various applications but are most often chosen to protect the basic metal, the basic product, from outer influences. Even two metallic parts within an assembly are capable of attacking each other by forming a galvanic cell, the same way a basic material may react adversely to its coating if chosen improperly. Evaluation of the possibility of a galv anic couple formation must therefore be considered when choosing the type and amount of protection a coating should ofer.This involves a survey of whether the coating is in its nature cathodic or anodic toward the metal underneath it. For example, a steel may be protected from other influences by nickel or zinc coating,even though nickel is cathodic to iron and zinc is anodic. Nickel protects the steel by successfully blocking the influence of the outer corrosive environment on the material, for the purpose of which, such coating must be free of pores. Zinc provides protection by corroding more readily than steel, and a by-product of the corrosive reaction, zinc oxide, being quite sizable, impairs the corrosive process and protects the coated material. Many metals are capable of forming oxide films, whichwhen stabilizedact as a protective coating for that particular material. Aluminum oxides thrive in acidic atmospheres,where they form thick protective layers, but once the basic alloy is anodized, the coating shrinks, turning thin, hard, and stable. Some ox ides, such as those of tin, zinc, titanium, and others, could be stabilized by an additional chemical or electrochemical treatment, which will turn them into protective layers for the basic metal material. The success of such protection depends on proper analysis of the galvanic-cell process,during which an anodically dissolvable metal must be protected by an equal and opposite cathodic reaction.14-9-1 ElectroplatingThe electroplating process should actually be called galvanizing, since it uses the principle of a galvanic couple between the plated part and plating material to transfer particles of material to the surface of the part. In this process, a direct electric current is applied to a solution of metal salts in which the parts to be coated are deposited. These parts assume the role of the cathode, or negative pole, by being connected to the negative end of the source of energy. Large parts are left hanging off a copper bar attached to the negative pole of the source, and small items, such as washers or bolts, are placed in wire baskets. The coating metal itself acts as an anode, and it is added to the bath in the form of plates, bars, or extruded shapes. When affected by the electric current, the anodic metal material slowly ionizes, its particles entering the solution of the bath. These lttle ions travel toward the cathodic-polarized part, on whose surface they become deposited in the form of metal crystals. Some types of metal-coating processes require coating baths to be heated and sometimes a liquidstirring action is added to enhance the uniformity of th
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