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附录A级进模的热处理的并行设计传统的级进模设计,主要是经验或半经验,脱离制造过程。在设计完成之前,级进模计划通常一再修改,从而形成一些弊端。如开发期长、成本高、效果不实用。由于对精确、使用寿命、开发成本和时间有很高的要求,现代级进模设计和制造应该很完全。因此,越来越多的先进技术和创新已经被应用,例如并行工程、灵活制造、虚拟制造、合作设计等。级进模的热处理是与设计、制造和装配同等重要的,因为它对制造、装配和服务具有重要影响。级进模的设计和制造进步很快。但在它们背后热处理严重滞后。级进模工业的发展,热处理必须保证级进模有好的状态及制造、装配和抗磨损性要求。热处理可以影响级进模生产比如过硬和软、装配。传统的热处理过程和方法提出了按设计提出的方式。这会使设计者和级进模及热处理偏离对方,设计者和级进模不能完全实现热处理过程中,材料特性、创意设计了解甚少的服务环境和设计思想。这些分歧将影响级进模进度。 因此,如果程序设计热处理是在早期设计阶段,目标是缩短开发时间、降低成本、稳定质量, 实现了从传统的发展模式,同时并行顺序将会实现。并行工程是把电脑整合系统设计为载体,在每个阶段开始后,工厂要考虑,例如制造、热处理、成本等因素,以避免错误。并行方式驳回有缺陷的连续方式,给连续方式带来一场革命。在当前的工作,同时结合热处理的情况下,死亡和发展模式,并进行了系统的研究和深刻。1热处理下的并行处理并行方式与顺序方式最终不同。对于顺序方式,主要考虑级进模的结构设计,几乎没有考虑到过程,这样的错误很容易扩散倒退。同时,设计部门很少与组装、销售部门和成本核算沟通。这些问题势必影响级进模的开发进度和市场前景。而并行方式,政府部门之间的密切关系,各有关部门参加级进模的发展和进步,与买家有着密切联系。这有利于消除部门之间的矛盾,提高效率,降低成本。在并行方式中的热处理,没有经费的情况后,采取了蓝图,但在级进模的设计,这样做,有利于优化热处理过程中充分利用潜力的材料。2 CAD/CAM在级进模热处理一体化中的应用可以看出设计和模拟过程是热处理一体化框架的核心。在信息输入透过产品设计及模块热处理过程中产生的经热处理、计算机辅助设计工程将自动把尺寸分割为部分绘画网、模拟温度场微观结构分析后热处理和缺陷可能出现的(如过热,在燃烧) 然后热处理过程中,如果被判定是根据优化结果由立体再现技术。此外理想工具和夹具、计算机辅助设计处纳入该系统。同时将根据工程范围内的信息与其它部门共享。这使热处理过程和优化过程,确保良好。2.1 3-D模型与立体展望技术对于热处理技术 级进模具的材料、结构和规模的问题,根据热处理及级进模可以通过3-D模型尽早发现。模型和阶段加热条件下转变为在级进模具和热处理工是可行的,因为它已经突破的计算阶段转变定律,形成跨阶段,第一阶段重点,强调热、热转移等。例如,立体热算法进行模型/地方取暖和复杂的印象和不对称级进模,微结构改造模型软件使用。 计算机能把目前的温度、压力和微观结构展示在任意时间和程序,整个改造立体配套的温度场、压力和微结构领域方面。 如果能结合成本、各种部分成本可以由电脑预测。2.2热处理过程设计 由于特殊的要求编制,硬度、表面粗糙度和在扭曲级进模具热处理中,包括输入参数中类型、温度和输入温度和时间的磨炼,必须正确选择,是否使用化学或表面淬火热处理参数,必须正确地确定。很难确定完全由电脑参数。 由于电脑技术的迅速发展。近十几年,难以大规模计算过。模拟和财产的权衡,需要的时间和成本热处理后,不难优化热处理过程。2.3热处理数据库 热处理数据库的描述。数据库提供了基础热处理过程。一般分为材料热处理数据库及数据库过程数据库。这是必然趋势预测和处理成本物资。虽然很难建立一个成本数据库,必须建立数据库的一系列试验。包括钢铁材料数据库等级、化学成分、性能及国内外级平行表。 数据库包括热处理过程、阶级、保温时间和冷却速度。 基于数据库,可热处理过程中产生的规则推断。 2.4 热处理设备和工具 热处理过程被确定后,工具和CAD/CAE系统设备转移设计制造的消息到数控装置。通过快速成型机床、夹具和工具的可靠性来判断。整个程序用网络转移,没有人为的干扰。3关键技术 3.1耦合温度、微结构、压力和成本 热处理程序是温度程序、程序强调、微观结构的互动。三个因素都影响成本。在加热和冷却、压力和热转换会出现在微观结构的变化。微观结构和微观结构的温度变化的温度和压力彼此交流的成本。研究这四个因素相互作用有了很大发展,但还没有普遍建立数学模型。许多模型试验很好配合,但不能付诸实施。最困难的分析解决问题的模式,采用数字方式,计算有误。即使如此,比较有经验的定性分析方法,使得计算机模拟热处理重大进展。3.2建立和整合模式 级进模具的设计、制造、热处理、装配、维修等发展模式。要有自己的模式和数据库. 他们通过彼此的实体关系模式成为一个系列。通过建立和利用强有力的推论机制,优化设计的目的是能够实现的。产品模型和其他模型建立了关系。产品款式变化的情况下改变基本模型。事实上,它是属于级进模具的数据。热处理后并入系统模型,它不再是一个孤立的单位,而其他成员关系密切的系统模型。经过搜查,从热处理数据库的计算和推理、热处理程序,受级进模具的几何模型、制造模型和成本的代价的限制被获得。如果不服从限制,系统会发出解释性警报。各设计单位通过网络联系。3.3成员之间的和谐与管理复杂的级进模具,需要项目组之间的密切合作。因为每个成员都考虑到短期全球级进模具的发展,必须加以管理和协调。首先,每个项目小组要确立自己的条件和资源管理的要求,加强学习的要求,并在规定的工作程序,以避免冲突。其次,要发展计划执行和监督机制应该建立。排除在适当发展情况下的阻塞。4结论(1) CAD/CAE已经应用到级进模具和热处理的并行设计和作图中,可以提高效率,很容易发现明显的矛盾和问题。(2) 级进模具的发展是在同一平台。在热处理过程中取得,设计者获得相关资料及其他设计可转让自营部门的信息平台。(3) 制定了正确的发展,及时调整计划,可大大缩短开发时间,并降低成本。附录BHeat Treatment of Die and Mould Oriented Concurrent DesignTraditional die and mould design,mainly by experience or semi-experience,is isolated from manufacturing processBefore the design is finalized,the scheme of die and mould is usually modified time and again,thus some disadvantages come into being,such as long development period,high cost and uncertain practical effectDue to strong desires for precision,service life, development period and cost,modern die and mould should be designed and manufactured perfectlyTherefore more and more advanced technologies and innovations have been applied, for example,concurrent engineering,agile manufacturing,virtual manufacturing,collaborative design,etcHeat treatment of die and mould is as important as design,manufacture and assembly because it has a vital effect on manufacture,assembly and service lifeDesign and manufacture of die and mould have progressed rapidly,but heat treatment lagged seriously behind t hemAs die and mould industry develops,heat treatment must ensure die and mould there are good state of manufacture,assembly and wear-resistant properties by requestImpertinent heat treatment caninfluence die and mould manufacturing such as over-hard and-soft andassemblyTraditionally the heat treatment process was made out according to the methods and properties brought forward by designerThis could make the designers of die and mould and heat treatment diverge from each other,for the designers of die and mould could not fully realize heat treatment process and materials properties,and contrarily the designers rarely understood the service environment and designing thoughtThese divergences will impact the progress of die and mould to a great extentAccordingly,if the process design of heat treatment is considered in the early designing stagethe aims of shortening development period,reducing cost and stabilizing quality will be achieved and t he sublimation of development pattern from serial to concurrent will be realizedConcurrent engineering takes computer integration system as a carrier,at the very start subsequent each stage and factors have been considered such as manufacturing,heat treating, properties and so forth in order to avoid the errorThe concurrent pattern has dismissed the defect of serial pattern,which bring about a revolution against serial patternIn the present work,the heat treatment was integrated into the concurrent circumstance of the die and mould development,and t he systemic and profound research was performed1 Heat Treatment Under Concurrent CircumstanceThe concurrent pattern differs ultimately from the serial patternWith regard to serial pattern, the designers mostly consider the structure and function of die and mould,yet hardly consider the consequent process,so that the former mistakes are easily spread backwardsMeanwhile, the design department rarely communicates with the assembling,cost accounting and sales departmentsThese problems certainly will influence the development progress of die and mould and the market foregroundWhereas in the concurrent pattern,the relations among departments are close,the related departments all take part in the development progress of die and mould and have close intercommunion with purchasersThis is propitious to elimination of the conflicts between departments,increase the efficiency and reduce the costHeat treatment process in the concurrent circumstance is made out not after blueprint and work-piece taken but during die and mould designingIn this way,it is favorable to optimizing the heat treatment process and making full use of the potential of the materials2 Integration of Heat Treatment CAD/ CAE for Die and MouldIt can be seen from that the process design and simulation of heat treatment are the core of integration frameAfter information input via product design module and heat treatment process generated via heat treatment CAD and heat treatment CAE module will automatically divide the mesh for parts drawing,simulation temperature field microstructure analysis after heat treatment and the defect of possible emerging (such as overheat,over burning),and then the heat treatment process is judged if the optimization is made according to the result reappeared by stereoscopic vision technologyMoreover tool and clamping apparatus CAD and CAM are integrated into this systemThe concurrent engineering based integration frame can share information with other branchThat makes for optimizing the heat treatment process and ensuring the process sound21 3-D model and stereoscopic vision technology for heat treatmentThe problems about materials,structure and size for die and mould can be discovered as soon as possible by 3-D model for heat treatment based on the shape of die and mouldModeling heating condition and phase transformation condition for die and mould during heat treatment are workable ,because it has been broken through for the calculation of phase transformation thermodynamics,phase trans formation kinetics,phase stress,thermal stress,heat transfer , hydrokinetics etcFor example,3-D heat-conducting algorithm models for equiflux / local heating complicated impression and asymmetric die and mould,and MARC software models for micro structure transformation was usedComputer can present the informations of temperature, microstructure and stress at arbitrary time and display the entire transformation procedure in t he form of 3-D by coupling temperature field,microstructure field and stress fieldIf the property can be coupled,various partial properties can be predicted by computer22 Heat treatment process designDue to the special requests for strength,hardness,surface roughness and distortion during heattreatment for die and mould,the parameters including quenching medium type,quenching temperature and tempering temperature and time,must be properly selected,and whether using surface quenching or chemical heat treatment the parameters must be rightly determinedIt is difficult to determine the parameters by computer fullySince computer technology develops quickly in recent decades,the difficulty with large-scale calculation has been overcomeBy simulating and weighing the property,the cost and the required period after heat treatment,it is not difficult to optimize the heat treatment process23 Data base for heat treatmentA heat treatment database is described inThe database is the foundation of making out heat treatment processGenerally,heat treatment database is divided into materials database and process databaseIt is an inexorable trend to predict the property by materials and process Although it is difficult to establish a property database,it is necessary to establish the database by a series of testsThe materials database includes steel grades,chemical compositions,properties and home and abroad grades parallel tablesThe process database includes heat treatment criterions,classes,heat preservation time and cooling velocityBased on the database,heat treatment process can be created by inferring from rules24 Tool and equipment for heat treatmentAfter heat treatment process is determined,tool and equipment CAD/ CAE system transfers the information about design and manufacture to the numerical control deviceThrough rapid tooling prototype,the reliability of tool and the clamping apparatus can be judgedThe whole procedure is transferred by network,in which there is no manmade interference3 Key Technique31 Coupling of temperature,microstructure,stress and propertyHeat treatment procedure is a procedure of temperature microstructure stress interactionThe three factors can all influence the propertyDuring heating and cooling,hot stress and transformation will come into being when microstructure changesTransformation temperature microstructure and temperature microstructure and stress property interact on each otherResearch on the interaction of the four factors has been greatly developed,but the universal mathematic model has not been builtMany models fit the test nicely,but they cannot be put into practiceDifficulties with most of models are solved in analytic solution,and numerical method is employed so that the inaccuracy of calculation existsEven so,comparing experience method with qualitative analysis,heat treatment simulation by computer makes great progress32 Establishment and integration of modelsThe development procedure for die and mould involves design,manufacture,heat treatment, assembly,maintenance and so onThey should have own database and modelThey are in series with each other by the entity-relation modelThrough establishing and employing dynamic inference mechanism,the aim of optimizing design can be achievedThe relation between product model and other models was builtThe product model will change in case the cell model changesIn fact,it belongs to the relation of data with die and mouldAfter heat treatment model is integrated into the system,it is no more an isolated unit but a member which is close to other models in the systemAfter searching,calculating and reasoning from the heat treatment database,procedure for heat treatment,which is restricted by geometric model,manufacture model for die and mould and by cost and property,is obtainedIf the restriction is disobeyedthe system will send out the interpretative warningAll design cell sare connected by communication network33 Management and harmony among membersThe complexity of die and mould requires closely cooperating among item groupsBecause each member is short of global consideration for die and mould development,they need to be managed and harmonized Firstly,each item group should define its own control condition and resource requested,and learn of the request of up and down working procedure in order to avoid conflictSecondly,development plan should be made out and monitor mechanism should be establishedThe obstruction can be duly excluded in case the development is hindered4 Conclusions(1)Heat treatment CAD/ CAE has been integrated into concurrent design for die and mould and heat treatment is graphed,which can increase efficiency,easily discover problems and clear conflicts(2) Die and mould development is performed on the same platformWhen the heat treatment process is made out,designers can obtain correlative information and transfer self-information to other design departments on the platform(3) Making out correct development schedule and adjusting it in time can enormously shorten the development period and reduce cost
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