模具专业毕业设计（论文）外文翻译-冷冲模具使用寿命的影响及对策.doc

冷冲模具使用寿命的影响及对策冲压模具概述冲压模具-在冷冲压加工中，将材料（金属或非金属）加工成零件（或半成品）的一种特殊工艺装备，称为冷冲压模具（俗称冷冲模）。冲压-是在室温下，利用安装在压力机上的模具对材料施加压力，使其产生分离或塑性变形，从而获得所需零件的一种压力加工方法。冲压模具的形式很多，一般可按以下几个主要特征分类： 根据工艺性质分类 （1）冲裁模 沿封闭或敞开的轮廓线使材料产生分离的模具。如落料模、冲孔模、切断模、切口模、切边模、剖切模等。 （2）弯曲模 使板料毛坯或其他坯料沿着直线（弯曲线）产生弯曲变形，从而获得一定角度和形状的工件的模具。 （3）拉深模 是把板料毛坯制成开口空心件，或使空心件进一步改变形状和尺寸的模具。（4）成形模 是将毛坯或半成品工件按图凸、凹模的形状直接复制成形，而材料本身仅产生局部塑性变形的模具。如胀形模、缩口模、扩口模、起伏成形模、翻边模、整形模等。根据工序组合程度分类（1）单工序模 在压力机的一次行程中，只完成一道冲压工序的模具。（2）复合模 只有一个工位，在压力机的一次行程中，在同一工位上同时完成两道或两道以上冲压工序的模具。 （3）级进模（也称连续模） 在毛坯的送进方向上，具有两个或更多的工位，在压力机的一次行程中，在不同的工位上逐次完成两道或两道以上冲压工序的模具。冲冷冲模全称为冷冲压模具。 冷冲压模具是一种应用于模具行业冷冲压模具及其配件所需高性能结构陶瓷材料的制备方法，高性能陶瓷模具及其配件材料由氧化锆、氧化钇粉中加铝、镨元素构成，制备工艺是将氧化锆溶液、氧化钇溶液、氧化镨溶液、氧化铝溶液按一定比例混合配成母液，滴入碳酸氢铵，采用共沉淀方法合成模具及其配件陶瓷材料所需的原材料，反应生成的沉淀经滤水、干燥，煅烧得到高性能陶瓷模具及其配件材料超微粉，再经过成型、烧结、精加工，便得到高性能陶瓷模具及其配件材料。本发明的优点是本发明制成的冷冲压模具及其配件使用寿命长，在冲压过程中未出现模具及其配件与冲压件产生粘结现象，冲压件表面光滑、无毛刺，完全可以替代传统高速钢、钨钢材料。 冷冲模具主要零件冷冲模具是冲压加工的主要工艺装备，冲压制件就是靠上、下模具的相对运动来完成的。加工时由于上、下模具之间不断地分合，如果操作工人的手指不断进入或停留在模具闭合区，便会对其人身安全带来严重威胁。（一）模具的主要零件、作用及安全要求 1工作零件凸凹模是直接使坯料成形的工作零件，因此，它是模具上的关键零件。凸凹模不但精密而且复杂，它应满足如下要求：（1）应有足够的强度，不能在冲压过程中断裂或破坏（2）对其材料及热处理应有适当要求，防止硬度太高而脆裂。 2定位零件定位零件是确定坯件安装位置的零件，有定位销（板）、挡料销（板）、导正销、导料板、定距侧刀、侧压器等。设计定位零件时应考虑操作方便，不应有过定位，位置要便于观察，最好采用前推定位、外廓定位和导正销定位等。 3压料、卸料及出料零件压料零件有压边圈、压料板等。 压边圈可对拉延坯料加压边力，从而防止坯料在切向压力的作用下拱起而形成皱褶。压料板的作用是防止坯料移动和弹跳。顶出器、卸料板的作用是便于出件和清理废料。它们由弹簧、橡胶和设备上的气垫推杆支撑，可上下运动，顶出件设计时应具有足够的顶出力，运动要有限位。卸料板应尽量缩小闭合区域或在操作位置上铣出空手槽。暴露的卸料板的四周应设有防护板，防止手指伸入或异物进入，外露表面棱角应倒钝。 4导向零件导柱和导套是应用最广泛的一种导向零件。其作用是保证凸凹模在冲压工作时有精确的配合间隙。因此，导柱、导套的间隙应小于冲裁间隙。导柱设在下模座，要保证在冲程下死点时，导柱的上端面在上模板顶面以上最少5至10毫米。导柱应安排在远离模块和压料板的部位，使操作者的手臂不用越过导柱送取料。 5支承及夹持零件它包括上下模板、模柄、凸凹模固定板、垫板、限位器等。上下模板是冷冲模具的基础零件，其他各种零件都分别安装固定在上面。模板的平面尺寸，尤其是前后方向应与制件相适应，过大或过小均不利于操作。 有些模具（落料、冲孔类模具）为了出件方便，需在模架下设垫板。这时垫板最好与模板之间用螺钉连接在一起，两垫板的厚度应绝对相等。垫板的间距以能出件为准，不要太大，以免模板断裂。 6紧固零件它包括螺钉、螺母、弹簧、柱销、垫圈等，一般都采用标准件。冷冲模具的标准件用量较多，设计选用时应保证紧固和弹性顶出的需要，避免紧固件暴露在表面操作位置上，防止碰伤人手和妨碍操作。 冷冲模具的发展改革开放以来，随着国民经济的高速发展，市场对冷冲模具的需求量不断增长。近年来，冷冲模具工业一直以15%左右的增长速度快速发展，冷冲模具工业企业的所有制成分也发生了巨大变化，除了国有专业模具厂外，集体、合资、独资和私营也得到了快速发展。 随着与国际接轨的脚步不断加快，市场竞争的日益加剧，人们已经越来越认识到产品质量、成本和新产品的开发能力的重要性。而冷冲模具制造是整个链条中最基础的要素之一，冷冲模具制造技术现已成为衡量一个国家制造业水平高低的重要标志，并在很大程度上决定企业的生存空间。近年许多冷冲模具企业加大了用于技术进步的投资力度，将技术进步视为企业发展的重要动力。一些国内模具企业已普及了二维cad，并陆续开始使用ug、pro/engineer、i-deas、euclid-is等国际通用软件，个别厂家还引进了moldflow、c-flow、dynaform、optris和magmasoft等cae软件，并成功应用于冲压模的设计中。以汽车覆盖件模具为代表的大型冲压模具的制造技术已取得很大进步，东风汽车公司模具厂、一汽模具中心等模具厂家已能生产部分轿车覆盖件模具。此外，许多研究机构和大专院校开展模具技术的研究和开发。经过多年的努力，在模具cad/cae/cam技术方面取得了显著进步；在提高模具质量和缩短模具设计制造周期等方面做出了贡献。虽然中国冷冲模具工业在过去十多年中取得了令人瞩目的发展，但许多方面与工业发达国家相比仍有较大的差距。例如，精密加工设备在冷冲模具加工设备中的比重比较低；cad/cae/cam技术的普及率不高；许多先进的模具技术应用不够广泛等等，致使相当一部分大型、精密、复杂和长寿命冷冲模具依赖进口。 随着科学技术的不断进步,现代工业产品的生产日益复杂与多样化,产品性能和质量也在不断提高,因而对冷冲压技术提出了更高的要求.为了使冷冲压技术能适应各工业部门的需要,冷冲压技术自身也在不断革新和发展.冷冲压技术的发展思路就是尽可能地完善和扩充冷冲压工艺的优点,克服其缺点.在冷冲压技术的发展过程中,应注意以下几方面：(1)冷冲压技术的发展过程中应正确地确定工艺参数及冷冲模具工作部分的形状与尺寸,提高冲压件的质量、缩短新产品试制周期,应在加强冲压成形理论研究的基础上,使冲压成形理论达到能对生产实际起指导作用,逐步建立起一套密切结合生产实际的先进的工艺分析计算方法.国外已开始采用弹塑性有限元法对汽车覆盖零件的成形过程进行应力应变分析和计算机模拟,以预测某一工艺方案对零件成形的可能性和可能出现的问题。(2)加快产品更新换代,克服模具设计周期长的缺点.应大力开展模具计算机辅助设计和制造(cad/cam)技术的研究.在我国,目前要特别注意加强多工位级进模cad/cam技术的研究。(3)满足大量生产需要以及减轻劳动强度.应加强冷冲压生产的机械化和自动化研究,使一般中、小件能在高速压力机上采用多工位级进模生产,达到生产高度自动化,进一步提高冲压的生产率。(4)扩大冷冲压生产的运用范围.使冷冲压既适合大量生产,也适合小批量生产;既能生产一般精度的产品,也能生产精密零件.应注意开发如精密冲裁(特别是厚料精冲)、高能成形、软模成形、施压和超塑性加工等新成形工艺,还要推广简易模(软模和低熔点合金模)、通用组合模、数控冲床等设备的运用。此外,对冲压板料性能的改进,模具新材料、模具新加工方法的开发也应进一步加强。冷冲模具使用寿命的影响及对策冷冲模具的使用寿命是以冲制出的工件数量来计算的。影响冷冲模寿命的因素很多。主要有模具结构设计、制造模具所用凸模和凹模的材料、模具的热处理质量与表面强化、冲模零件的制造精度和冷冲压材料的选取。除此之外，还有冲模的安装、调整、使用以及维修等。1模具设计对寿命的影响(1)排样设计的影响排样方法与搭边值对模具寿命的影响很大，过小的搭边值，往往是造成模具急剧磨损和凸、凹模啃伤的重要原因。从节约材料出发，搭边值愈小愈好，但搭边值小于一定数值后，对模具寿命和剪切表面质量不利。在冲裁中有可能被拉人模具问隙中，使零件产生毛刺，甚至损坏模具刃口，降低模具寿命。因此，在考虑提高材料利用率的同时，必须根据零件产量、质量和寿命，确定排样方法和搭边值。(2)凹模结构的影响对容易产生应力集中而开裂的凹模结构，可以采用组合结构或镶拼结构，以及预应力结构，从而提高模具使用寿命。(3)间隙的影响当间隙过小时，压缩挤压利害，摩擦力增大，磨损增大，侧面的磨损加剧，冲裁后卸料和推件时，材料与凸、凹模之间的摩擦还将造成刃口侧面的磨损比端面的磨大大，同时也容易造成凸、凹模温度很高，把金属碎屑吸附在刃口侧面，形成金属瘤，使凸、凹模出现崩刃或胀裂现象。因此，过小的间隙对模具寿命极为不利。间隙太大，会增加凸模与凹模端面边缘的集中应力，致使压应力急剧增加，于是刃口边很快屈服变形而失去棱角。因此又增加了冲裁力，进而使刃口边更快磨损，降低模具寿命。但为了减小凸、凹模的磨损，延长模具使用寿命，在保证冲裁件质量的前提下，设计时适当采用较大间隙是十分必要的。(4)模具导向结构对寿命的影响可靠的导向对于减小工作零件的磨损，避免凸、凹模啃伤是非常有效的。特别对无问隙或小问隙冲裁模、复合模和多工位级进模更为重要。为提高模具寿命，必须根据工序和零件精度要求，正确选择导向形式和导向精度，所选择导向精度应高于凸、凹模的配合精度。(5)冷冲压材料选取的影响冷冲压材料应满足制件的设计要求和冲压工艺要求，否则容易损伤模具，降低模具使用寿命。冷冲压材料表面质量不好，冲压时制件易破裂，也易擦伤模具。冷冲压材料塑性不好，变形量小，冲压时制件易破裂，也易擦伤模具。另外，材料的厚度公差应符合国家标准。因为一副冲模适用于一定材料的厚度，成形、弯曲、翻边、引伸模具的凸、凹模结构间隙是直接根据材料厚度来确定的。所以材料厚度不均匀，会导致废品产生和模具损坏。2模具材料对模具寿命的影响模具材料对模具寿命的影响是模具材料性质、化学成分、组织结构、硬度和冶金质量等的综合反映。其中，材料性质和热处理质量影响最为明显。模具材料性质对模具寿命的影响是很大的。如将同一种工件，使用不同的模具材料做弯曲试验，试验结果：用9mn2v材料，其寿命为5万次；用crl2mov渗氮，其寿命可达40万次。因此，在选用材料时，应根据制件的批量大小，合理选用模具材料。模具工作零件的硬度对模具寿命的影响也很大。但并不是硬度愈高、模具寿命愈长。这是因为硬度与强度、韧性及耐磨性等有密切的关系。有的冲模要求硬度高，寿命长。如采用t10钢制造冲模，硬度为5458hrc，只冲几千次，制件毛刺就很大。如果将硬度提高到6064hrc，则刃磨寿命可达23万次。但如果继续提高硬度，则会出现早期断裂。有的冲模硬度不宜过高，如采用crl2mov制造凹模硬度为5862hrc时，一般寿命为23万件，失效形式是崩刃和开裂以及如果将硬度降到5458hrc，寿命提高到56万件，但硬度降低到5053hrc会出现凹模刃口易磨钝现象。由此可见，模具硬度必须根据材料性质和失效形式而定。应使硬度、强度、韧性及耐磨性、耐疲劳强度等达到特定冲压工序所需要的最佳配合。3模具的热处理质量与表面强化对寿命的影响模具的热处理质量对模具的性质与使用寿命影响很大。实践证明，模具工作零件的淬火变形与开裂，使用过程中早期断裂，虽然与材料的冶金质量、锻造质量、模具结构及加工有关，但与模具的热处理关系更大。根据模具失效原因的分析统计，热处理不当引起的失效占50 以上。实践证明，高级的模具材料必须配以正确的热处理工艺，才能真正发挥材料的潜力。模具工作零件表面强化处理的目的，是获得外硬内韧的效果，从而得到硬度、耐磨性、韧性、耐疲劳强度的良好配合。模具表面强化处理方法很多，表面处理的新技术工艺发展很快。除氮碳共渗和离子氮化、渗硼、渗铌、渗钒、表面镀硬铬和电火花强化外，化学气相沉积(cvd)和物理气相沉积(pvd)已逐步采用。经cvd和pvd处理后，模具表面覆盖一层超硬物质，如tic、tin等。硬度极高、耐磨性、耐蚀性、抗黏合性很好，可提高模具寿命几倍到几十倍。4冲模零件的制造精度对模具寿命的影响冲模制造的精度与使用寿命关系很大，特别是模具表面粗糙度对模具影响很大。如用crl2mov钢制造落料模，如果表面粗糙度值r =16 m时，其寿命为3万件左右。如经精抛光，表面粗糙度值r =04 m，寿命可提高到45万件。因此，对模具工作零件表面，一般都要经过磨削、研磨、抛光等精加工和精细加工。5其他方面对模具寿命的影响(1)压力机的精度不高，也易使冲模损坏。(2)冲模在压力机上安装的正确与否及操作者的技术水平高低，对模具寿命也有很大影响。(3)冲模的保管和维护好坏，以及使用润滑剂的情况，也影响模具使用寿命。6结语在实际生产中，对于薄板冲模使用，很少出现非正常磨损的情况。但对于厚板冲模时则发现易出现非正常磨损，我们总是针对出现的问题进行研究总结。因为一副冷冲模，从设计、加工制造、装配、调试到安装、使用，都耗费了众多工时，同时冲模的凸、凹模使用的材料，大都是优质合金钢。因此，冲模的成本都是比较高的。所以在生产中了解影响冲模寿命的因素及采取相应的对策来指导生产，具有重大的现实意义。 die life of cold stamping die and mprovementsoverview of stamping die stamping die - stamping in the cold, the material (metal or non-metallic) processing into parts (or half) of a special technical equipment, called cold stamping die (commonly known as die). press - is at room temperature, using the die installed in the press to put pressure on the material to produce a separation or plastic deformation, and thus to obtain the necessary parts of a pressure processing method. stamping die in the form of many, the general categories according to the following main features: 1. according to the technical nature of (1) die along the closed or open contour the material are derived from mold. if blanking die, punch die, cut off the mold, cut mode, cutting mode, split mode, etc. (2) bending mode to blank or blank sheet along a straight line (curved line) to bend, deform, and thus obtain a certain angle and shape of the workpiece in the mold. (3) the drawing die is made of the blank sheet opening hollow, or hollow pieces of further changes to the shape and size of the mold. (4) die rough or semi-finished workpiece is convex according to plan, direct copy the shape of the die shape, the material itself, generate only local plastic deformation of the mold. such as the bulging mode, reducing the die, expansion die, forming die rolling, flanging mold, plastic mold. 2. according to the degree classification process combination (1) single process model in a press tour, just completed a die stamping process. (2) composite model is only one station, in a press tour, at the same station at the same time to complete more than two or two die stamping process. (3) progressive die (also known as the modulus of continuity) in the feeding direction, rough, with two or more of the station, at the press of a visit, work in different places on the completion of two or two successive road over stamping die process. chong called cold stamping die die-wide. cold stamping die is used in cold stamping die mold industry, and accessories required for high-performance structural ceramic materials, preparation methods, high-performance ceramic materials, molds and accessories from the zirconium oxide and yttrium aluminum powder increases, pr element composition, preparation is the solution of zirconia, yttria solution, praseodymium oxide solution, according to a certain percentage of alumina solution when mixed liquor, ammonium bicarbonate infusion, by co-precipitation synthesis of ceramic materials, molds and accessories needed for raw materials, reaction precipitate generated by the treatment, drying, calcining and accessories by high performance ceramic mold material superfine powder, and then after forming, sintering, finishing, they will have high-performance ceramic materials, molds and accessories. advantages of this invention is the invention made of cold stamping dies and parts and long service life, the process does not appear in the press and its parts and stamping die bond generated the phenomenon of stamping surface is smooth, no glitches, can replace traditional high-speed steel, tungsten steel. die with the main parts die stamping tools is the main process equipment, stamping rely on the relative movement under the mold completed. processing time because the upper and lower mold between the constant division and, if continued operation of the fingers of workers to enter or remain in the mold closed, there will certainly pose a serious threat to their personal safety. (a) of the mold main parts, function and safety requirements 1. working parts is a direct punch to blank forming the working parts, therefore, it is the key to mold parts. punch not only sophisticated and complex, it should meet the following requirements: (1) be of sufficient strength, can not be broken or destroyed during stamping. (2) should be appropriate to its material and heat treatment requirements, to prevent too high hardness and brittle fracture. 2. positioning parts positioning part is to determine the location of the parts installed blank, there are pins (board), gauge pin (plate), lead is sold, guide plate, knife set from the side, side pressure etc. design should be considered when positioning parts easy to operate and should not have had orientation, location to facilitate observation, preferably in the forward position, contouring to correct the pin location and positioning. 3. binder, unloading and discharging parts binder components are blank holder, binder board. blank holder pressure can drawing blank holder force, thereby preventing billets under the action of the tangential pressure arch formed folds. the role of pressure plate to prevent movement and bounce blank. top of the device, discharge boards role is to facilitate the pieces and clean up waste. them by the spring, rubber and equipment, putting on the air-cushion support, can move up and down, knocking out pieces of the design should have enough top output, movement to the limited spaces. stripper plate area should be minimized or closed position in the operating groove milling out empty-handed. exposure of the stripper plate should have protection around the plate, to prevent finger inserted into or foreign objects inside, exposed surface edges should be blunt down. 4. guide parts and guide sleeve guide pin is the most widely used part of a guide. its role is to ensure punch the punching clearance when accurate match. therefore, the guide posts, guide cover the gap should be less than the blanking clearance. guide post located next mold base, to ensure that the stroke bottom dead center, the lead column in the template on the face over the top for at least 5 to 10 mm. guide columns should be arranged far away from the module and the pressure plate in the area, so the operators arms do not get to take over the lead column material. 5. supporting and clamping the upper and lower parts which includes templates, die handle, fixed plate punch, plate, stopper, etc. up and down the template is the basis of the cold die parts, other parts are respectively fixed at the top. template plane size, especially around the direction to be compatible with the workpiece, too large or too small are not conducive to action. some molds (blanking, punching type mold) to the pieces of convenience, be set up under the mold plate. at this time the best and the template plate connected between the screw, the two plate thickness should be absolutely equal. plate spacing out the pieces to be able to prevail, not too much, so as not to break the template. 6. fastening parts which includes screws, nuts, springs, pins, washers, etc., are generally used standard parts. die more with the amount of standard parts, design choice and flexibility should be tightened to ensure the top out of the need to avoid exposure to the surface fastener operating position, the staff and impede operation to prevent bumps. die with the development of since reform and opening, with the rapid development of the national economy, the market demand with the growing die. in recent years, die with the industry has been around 15% growth rate of the rapid development of industrial enterprises with ownership die components also changed dramatically, in addition to the professional mold factory outside of state-owned, collective, joint ventures, wholly-owned and private has been a rapid development. as with the accelerating pace of international integration, the increasing competition in the market, it has been increasingly recognized product quality, cost, and new product development capacities. the cold die manufacturing is the most basic elements of the chain, one of the cold die manufacturing technology to measure a countrys manufacturing sector has become an important symbol of the level, and largely determine the viability of enterprises. die with enterprises to increase in recent years many technological advances for investment, technological progress will be seen as an important driving force for enterprise development. some domestic enterprises have popularized the two-dimensional mold cad, and gradually began to use ug, pro / engineer, i-deas, euclid-is and other international common software, individual manufacturers have also introduced moldflow, c-flow, dynaform, optris and magmasoft etc. cae software, and successfully applied in stamping die design. a car cover mold as the representative of a large stamping die manufacturing technology has made great progress, dongfeng motor corporation mold factory, mold manufacturers such as faw mold center has been able to produce some car cover mold. in addition, many research institutions and universities to carry out technology research and development of mold. after years of effort, in the mold cad / cae / cam technology has made remarkable progress; in improving quality and reducing mold die design and manufacturing cycle, and so contributed. although china die with the industry over the past decade has made remarkable development, but in many ways compared with the industrialized countries there is still a large gap. for example, the precision machining equipment, processing equipment in die with the relatively low proportion; cad / cae / cam technology penetration is not high; many advanced mold technology not widely so, resulting in a considerable number of large, sophisticated, complex and long die life with dependence on imports. with the continuous progress of science and technology, modern industrial production of increasingly complex and diverse, product performance and quality is ever increasing, thus the cold stamping technology put forward higher requirements. in order to adapt to the cold stamping technology industry needs, cold stamping technology itself also in innovation and development. cold stamping technology idea is to improve and expand as much as possible the advantages of the cold stamping process, to overcome its shortcomings. in the cold stamping technology development, should note the following aspects: (1) cold stamping technology process parameters should be properly identified and die with the work of some of the shape and size, to improve the quality of stamping parts and shorten the new product production cycle should be in strengthening the metal forming the basis of theoretical studies, to metal forming theory to practice can produce a direction, and gradually establish a close connection with the actual production of the advanced process of calculation. abroad have begun to use plastic finite element method, automobile parts forming process of the stress and strain analysis and computer simulation to predict the forming part of a process plan on the possibilities and potential problems. (2) to accelerate product replacement, mold design to overcome the shortcomings of a long cycle. should vigorously carry out computer-aided design and manufacture of molds (cad / cam) research. in my country, paying particular attention to strengthening the multi-position progressive die cad / cam technology. (3) to meet the needs of mass production, and reduce labor intensity. should strengthen cold stamping of mechanized and automated, so that the average, small pieces of high-speed presses in a multi-position progressive die production, production reached a high degree of automation to further improve stamping productivity. (4) expand the scope of application of cold stamping production. so cold pressing both suitable for mass production, but also for small batch production; both the general accuracy of product production, but also can produce precision parts. should pay attention to development such as fine blanking (especially thick material fine blanking), forming high-energy, soft mold forming, pressure and processing new superplastic forming process, but also promote the easy mode (soft mode and the low melting point alloy mold), universal hybrid model, the use of cnc punch press and other equipment. in addition, the performance improvement of sheet metal stamping, mol