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《冲压模具基础》课程教学大纲课程编号：课程英文译名：课内总学时:72学时学分：4。
5学分课程类别：必修课开课对象：汽车制造与装配技术专业执笔人：编写日期:一、课程性质、目的和任务《冲压模具设计与制造》是汽车制造及汽车整形专业的一门主干专业技术课，它是一门将冲压成形加工原理、冲压设备、冲压工艺、冲模设计与冲模制造有机融合，综合性和实践性较强的课程。
其目的是使学生了解冲压变形规律,认识冲压成形工艺方法，冲压模具结构，冲压模具制造方法与手段，掌握冲压模具设计与计算方法，掌握冲压工艺与模具设计方法，冲压模具制造工艺方法，能进行中等冲压零件的冲压工艺编制,冲模设计与冲模制造工艺编制，并培养学生发现问题、分析问题和解决问题的能力，培养学生逻辑思维能力，为毕业设计及毕业以后从事专业工作打下必要的基础。
二、教学基本要求本课程是冲压模具设计与计算，冲压模具结构,模具制造工艺方法为重点。
学外本课程应达到以下基本要求：1、能应用冲压变形理论,分析中等复杂冲压件变形特点，制定合理冲压工艺规程的能力。
2、协调冲压设备与模具的关系，选择冲压设备的能力。
3、熟悉掌握冲模设计计算方法，具备中等复杂冲模结构选择和设计的能力，所设计的冲模应工作可行、操作方便、便于加工和装配,技术经济性好。
4、具备正确选择冲压模具加工方法，制定中等复杂冲模制造工艺和装配工艺的能力.5、初步具备进行多工位级进模设计和制造的能力。
6、初步具备进行分析和处理试模过程中产生的有关技术问题的能力。
三、教学内容及要求：第1章冲压模具设计与制造基础1.1 冲压成形与模具技术概述掌握冲压与冲模概念;冲压工序的分类；冲模的分类；冲模设计与制造的要求；了解冲压现状与发展方向。
1.2 冲压设备及选用了解常见冲压设备；掌握冲压设备的选用；模具的安装。
1.3 冲压变形理论基础掌握塑性变形的概念；理解塑性力学基础；掌握金属塑性变形的一些基本规律；冲压材料及其冲压成形性能.1.4 模具材料选用掌握冲压对模具材料的要求;冲模材料的选用原则;冲模常见材料及热处理要求。
Characteristics and Sheet Metal Forming1．The article overviewStamping is a kind of plastic forming process in which a part is produced by means of the plastic forming the material under the action of a die. Stamping is usually carried out under cold state, so it is also called stamping. Heat stamping is used only when the blank thickness is greater than 8~100mm. The blank material for stamping is usually in the form of sheet or strip, and therefore it is also called sheet metal forming. Some non-metal sheets (such as plywood, mica sheet, asbestos, leather)can also be formed by stamping. Stamping is widely used in various fields of the metalworking industry, and it plays a crucial role in the industries for manufacturing automobiles, instruments, military parts and household electrical appliances, etc.The process, equipment and die are the three foundational problems that needed to be studied in stamping.The characteristics of the sheet metal forming are as follows:(1) High material utilization(2) Capacity to produce thin-walled parts of complex shape.(3) Good interchangeability between stamping parts due to precision in shapeand dimension.(4) Parts with lightweight, high-strength and fine rigidity can be obtained.(5) High productivity, easy to operate and to realize mechanization and automatization.The manufacture of the stamping die is costly, and therefore it only fits to mass production. For the manufacture of products in small batch and rich variety, the simple stamping die and the new equipment such as a stamping machining center, are usually adopted to meet the market demands.The materials for sheet metal stamping include mild steel, copper, aluminum, magnesium alloy and high-plasticity alloy-steel, etc.Stamping equipment includes plate shear punching press. The former shears plate into strips with a definite width, which would be pressed later. The later can be used both in shearing and forming.2．Characteristics of stamping formingThere are various processes of stamping forming with different working patterns and names. But these processes are similar to each other in plastic deformation. There are following conspicuous characteristics in stamping:（1）．The force per unit area perpendicular to the blank surface is not large but is enough to cause the material plastic deformation. It is much less than the inner stresses on the plate plane directions. In most cases stamping forming can be treated approximately as that of the plane stress state to simplify vastly the theoretical analysis and the calculation of the process parameters.（2）．Due to the small relative thickness, the anti-instability capability of the blank is weak under compressive stress. As a result, the stamping process is difficult to proceed successfully without using the anti-instability device (such as blank holder). Therefore thevarieties of the stamping processes dominated by tensile stress are more than dominated by compressive stress.（3）．During stamping forming, the inner stress of the blank is equal to or sometimes less than the yield stress of the material. In this point, the stamping is different from the bulk forming. During stamping forming, the influence of the hydrostatic pressure of the stress state in the deformation zone to the forming limit and the deformation resistance is not so important as to the bulk forming. In some circumstances, such influence may be neglected. Even in the case when this influence should be considered, the treating method is also different from that of bulk forming.（4）．In stamping forming, the restrain action of the die to the blank is not severs as in the case of the bulk forming (such as die forging). In bulk forming, the constraint forming is proceeded by the die with exactly the same shape of the part. Whereas in stamping, in most cases, the blank has a certain degree of freedom, only one surface of the blank contacts with the die. In some extra cases, such as the forming of the blank on the deforming zone contact with the die. The deformation in these regions are caused and controlled by the die applying an external force to its adjacent area.Due to the characteristics of stamping deformation and mechanics mentioned above, the stamping technique is different form the bulk metal forming:（1）．The importance or the strength and rigidity of the die in stamping forming is less than that in bulk forming because the blank can be formed without applying large pressure per unit area on its surface. Instead, the techniques of the simple die and the pneumatic and hydraulic forming are developed.（2）．Due to the plane stress or simple strain state in comparison with bulk forming, more research on deformation or force and power parameters has been done. Stamping forming can be performed by more reasonable scientific methods. Based on the real time measurement and analysis on the sheet metal properties and stamping parameters, by means of computer and some modern testing apparatus, research on the intellectualized control of stamping process is also in proceeding.（3）．It is shown that there is a close relationship between stamping forming and raw material. The research on the properties of the stamping forming, that is, forming ability and shape stability, has become a key point in stamping technology development, but also enhances the manufacturing technique of iron and steel industry, and provides a reliable foundation for increasing sheet metal quality.3．Categories of stamping formingMany deformation processes can be done by stamping, the basic processes of the stamping can be divided into two kinds: cutting and forming.Cutting is a shearing process that one part of the blank is cut from the other. It mainly includes blanking, punching, trimming, parting and shaving, where punching and blanking are the most widely used. Forming is a process that one part of the blank has some displacement from the other. It mainly includes deep drawing, bending, local forming, bulging, flanging, necking, sizing and spinning.In substance, stamping forming is such that the plastic deformation occurs in the deformation zone of the stamping blank caused by the external force. The stress state and deformation characteristic of the deformation zone are the basic factors to decide theproperties of the stamping forming. Based on the stress state and deformation characteristics of the deformation zone, the forming methods can be divided into several categories with the same forming properties and be studied systematically.The deformation zone in almost all types of stamping forming is in the plane stress state. Usually there is no force or only small force applied on the blank surface. When is assumed that the stress perpendicular to the blank surface equals to zero, two principal stresses perpendicular to each other and act on the blank surface produce the plastic deformation of the material. Due to the small thickness of the blank, it is assumed approximately the two principal stresses distribute uniformly along the thickness direction. Based on this analysis, the stress state and the deformation characteristics of the deformation zone in all kinds of stamping forming can be denoted by the points in the coordinates of the plane principal stresses and the coordinates of the corresponding plane principal strains.4．Raw materials for stamping formingThere are a lot of raw materials used in stamping forming, and the properties of these materials may have large difference. The stamping forming can be succeeded only by determining the stamping method, the forming parameters and the die structures according to the properties and characteristics of the raw materials. The deformation of the blank during stamping forming has been investigated quite thoroughly. The relationships between the material properties decided by the chemistry component and structure of the material and the stamping forming has been established clearly. Not only the proper material can be selected based on the working condition and usage demand, but also the new material can be developed according to the demands of the blank properties during processing the stamping part. This is an important domain in stamping forming research. The research on the material properties for stamping forming is as follows:（1）．Definition of the stamping property of the material.（2）．Method to judge the stamping property of the material, find parameters to express the definitely material property of the stamping forming, establish the relationship between the property parameters and the practical stamping forming, and investigate the testing methods of the property parameters.（3）．Establish the relationship among the chemical component, structure, manufacturing process and stamping property.The raw materials for stamping forming mainly include various metals and nonmetal plate. Sheet metal includes both ferrous and nonferrous metals. Although a lot of sheet metals are used in stamping forming, the most widely used materials are steel, stainless steel, aluminum alloy and various composite metal plates.5．Stamping forming property of sheet metal and its assessing methodThe stamping forming property of the sheet metal is the adaptation capability of the sheet metal to stamping forming. It has crucial meaning to the investigation of the stamping forming property of the sheet metal. In order to produce stamping forming parts with most scientific, economic and rational stamping forming process and forming parameters, it is necessary to understand clearly the properties of the sheet metal, so as to utilize the potential of the sheet metal fully in the production. On the other hand, toselect plate material accurately and rationally in accordance with the characteristics of the shape and dimension of the stamping forming part and its forming technique is also necessary so that a scientific understanding and accurate judgment to the stamping forming properties of the sheet metal may be achieved.There are direct and indirect testing methods to assess the stamping property of the sheet metal.Practicality stamping test is the most direct method to assess stamping forming property of the sheet metal. This test is done exactly in the same condition as actual production by using the practical equipment and dies. Surely, this test result is most reliable. But this kind of assessing method is not comprehensively applicable, and cannot be shared as a commonly used standard between factories.The simulation test is a kind of assessing method that after simplifying and summing up actual stamping forming methods, as well as eliminating many trivial factors, the stamping properties of the sheet metal are assessed, based on simplified axial-symmetric forming method under the same deformation and stress states between the testing plate and the actual forming states. In order to guarantee the reliability and generality of simulation results, a lot of factors are regulated in detail, such as the shape and dimension of tools for test, blank dimension and testing conditions(stamping velocity, lubrication method and blank holding force, etc).Indirect testing method is also called basic testing method its characteristic is to connect analysis and research on fundamental property and principle of the sheet metal during plastic deformation, and with the plastic deformation parameters of the sheet metal in actual stamping forming, and then to establish the relationship between the indirect testing results(indirect testing value) and the actual stamping forming property (forming parameters). Because the shape and dimension of the specimen and the loading pattern of the indirect testing are different from the actual stamping forming, the deformation characteristics and stress states of the indirect test are different from those of the actual one. So, the results obtained form the indirect test are not the stamping forming parameters, but are the fundamental parameters that can be used to represent the stamping forming property of the sheet metal.。
机械工业冲压工程术语标准冲压1 冲压工艺1.1 冲压sheet metal forming靠压力机和模具对板材、带材、管材及型材等施加外力，使之产生塑性变形或分离，从而获得所需形状和尺寸的冲压件成形加工方法。
1.2 冲压件 stamping采用冲压方法制成的工件或毛坯。
1.3 金属压力加工 mechanical working of metals利用金属的塑性，使其改变形状、尺寸和改善性能，以获得型材、棒材、板材、线材、锻件、冲压件的加工方法。
1.4 板料成形 sheet forming用板料、薄壁管、薄型材等作为原材料进行塑性加工的冲压方法。
1.5 冲压工艺路线 process chart of press按产品或零部件的冲压工艺编制的说明产品、零部件的工序、工序名称、工序内容、工艺参数、采用的设备和工艺装备等的工艺文件。
1.6 冲裁 blanking利用冲模将板料以封闭的轮廓与坯料分离的冲压方法。
1.7 落料 blanking利用冲裁取得一定外形制件或坯料的加工方法。
1.8 冲孔punching将坯料内的材料以封闭曲线和坯料分离开来，得到带孔制件的冲压方法。
1.9 切断 cut-off将坯料或工件切成两段或数段的冲压方法。
1.10 切口 notch将材料沿不封闭的曲线部分地分离开，其分离部分和材料发生形状变化的冲压方法。
1.11 切边 side scrap将拉深或成型后的半成品边缘部分多余材料切掉的冲压方法。
1.12 精密冲裁 fine blanking用压边圈使板料冲裁区处于静压作用下，抑制剪裂纹的发生，实现塑性变形分离的冲裁方法。
1.13 负间隙冲裁 negative clearance blanking在凸模直径大于凹模直径的模具内进行的冲裁方法。
1.14 对向凹模冲裁 opposed die blanking利用一个平端面凹模和一个带凸台的凹模使材料实现分离与整修的冲裁方法。
1.15 整修 shaving整修模沿冲裁件的外缘或内孔刮去一层薄薄的切屑，以提高冲裁件的加工精度和剪断面光洁度的加工方法。
影响镁合金板材冲压成形性能的因素魏 丽 付忠亮 李昌坤 王心朋(重庆大学 材料科学与工程学院 重庆 400044)摘 要：冲压是一种现代塑性成形方法，镁合金板的冲压性能及相关工艺的研究具有十分重要的意义。
探讨了镁合金材料本身、冲压加工工艺参数以及工艺方法等影响镁合金板料冲压性能的因素，指出了其中需要重点解决的关键问题。
关键词：镁合金板料、冲压成形、影响因素The Factors of Effecting the Punching Properties of MegnesiumAlloysWei Li Fu Zhongliang Li Changkun Wang Xinpeng(College of Material Science and Engineering of Chongqing University,Chongqing 400044)Abstract：Punching is a modern plastical deformation. And the study of the punching properties of megnesium alloys and the relation processing is very important . It discusses the factors of effecting the punching properties of megnesium alloys, which includes the material Characteristics, processing parameters and processing methods. Then it indicates the key problems which need to be solved importantly.Keywords：Megnesium alloy sheet , Punching deforming , the effective factors0 概述随着经济的快速发展，全球性能源和资源的紧缺问题日益严峻，降低能源消耗，提高能源利用率是工业生产的迫切需要，所以产品轻量化是工业发展的必然趋势。
1、冲压概念在室温下，利用安装在压力机上的模具对材料施加压力，对其产生分离或塑性变形，从而获得一定形状、尺寸精度的零件加工方法。
（冲压三要素：合理冲压工艺、先进的模具、高效的冲压设备）2、冷冲模在冲压加工中，将材料加工成零件（或半成品）的一种特殊工艺装备，称为冲压模具（俗称冲模）。
3、冲压工艺的特点低耗、高效、低成本“一模一样”、质量稳定、高一致性可加工薄壁、复杂零件板材有良好的冲压成形性能模具成本高所以，冲压成形适宜批量生产。
4、冲压工序分类根据材料变形特点分为分离工序和塑形成形工序。
分离工序：指板料在冲压力的作用下，变形部分的应力达到强度极限以后，使坯料发生断裂而产生分离。
（有：落料、冲口、剪切、切断、切槽、切口、切边等）塑形成形工序：指坯料在冲压力作用下，变形部分的应力达到屈服极限，但未超出抗拉强度极限，使板料产生塑性变形，成为具有一定形状、尺寸精度制件的加工工序（拉深、胀形、翻边等）5、冲压成型性能主要包括：成型极限（材料达到最大变形程度）和成型质量。
6、冲压件的质量指标尺寸精度、厚度变化、表面质量以及成形后材料的物理机械性能。
7、冲压成形对材料的要求主要体现在：材料成形性能、材料厚度公差、材料表面质量等。
8、冲裁件的工艺性是指冲裁件对冲压工艺的适应程度。
9、冲裁工序按工序的组合程度的分类单工序，复合和级进冲裁。
冲裁组合方式的选择根据冲裁件的生产批量、尺寸精度、形状复杂程度、模具成本等多方面考虑（1）生产批量（2）冲裁件的尺寸精度（3）对工件尺寸、形状的适应性（4）模具制造、安装调整和成本（5）操作方便与安全10、冲模的分类(1)按工序性质分：落料模、冲口模、切断模、整修模、弯曲模、拉深模，成形模等。
(2)按工序组合程度分为：单工序模、级进模、复合模。
级进模：一次行程中，在一副模具的不同位置上完成不同的工序。
因此对工件来说，要经过几个工位也即几个行程才能完成。
而对模具来说，则每个行程都能冲压出一个制件。
Characteristics of Stamping and Properties ofSheet Metal Forming1．overviewStamping is a kind of plastic forming process in which a part is produced by means of the plastic forming the material under the action of a die. Stamping is usually carried out under cold state, so it is also called stamping. Heat stamping is used only when the blank thickness is greater than 8~100mm. The blank material for stamping is usually in the form of sheet or strip, and therefore it is also called sheet metal forming. Some non-metal sheets (such as plywood, mica sheet, asbestos, leather)can also be formed by stamping.Stamping is widely used in various fields of the metalworking industry, and it plays a crucial role in the industries for manufacturing automobiles, instruments, military parts and household electrical appliances, etc.The process, equipment and die are the three foundational problems that needed to be studied in stamping.The characteristics of the sheet metal forming are as follows:(1)High material utilization(2)Capacity to produce thin-walled parts of complex shape.(3)Good interchangeability between stamping parts due to precision in shapeand dimension.(4)Parts with lightweight, high-strength and fine rigidity can be obtained.(5)High productivity, easy to operate and to realize mechanization and automatization.The manufacture of the stamping die is costly, and therefore it only fits to mass production. For the manufacture of products in small batch and rich variety, the simple stamping die and the new equipment such as a stamping machining center, are usually adopted to meet the market demands.The materials for sheet metal stamping include mild steel, copper, aluminum, magnesium alloy and high-plasticity alloy-steel, etc.Stamping equipment includes plate shear punching press. The former shears plate intostrips with a definite width, which would be pressed later. The later can be used both in shearing and forming.2．Characteristics of stamping formingThere are various processes of stamping forming with different working patterns and names. But these processes are similar to each other in plastic deformation. There are following conspicuous characteristics in stamping:（1）．The force per unit area perpendicular to the blank surface is not large but is enough to cause the material plastic deformation. It is much less than the inner stresses on the plate plane directions. In most cases stamping forming can be treated approximately as that of the plane stress state to simplify vastly the theoretical analysis and the calculation of the process parameters.（2）．Due to the small relative thickness, the anti-instability capability of the blank is weak under compressive stress. As a result, the stamping process is difficult to proceed successfully without using the anti-instability device (such as blank holder). Therefore the varieties of the stamping processes dominated by tensile stress are more than dominated by compressive stress.（3）．During stamping forming, the inner stress of the blank is equal to or sometimes less than the yield stress of the material. In this point, the stamping is different from the bulk forming. During stamping forming, the influence of the hydrostatic pressure of the stress state in the deformation zone to the forming limit and the deformation resistance is not so important as to the bulk forming. In some circumstances, such influence may be neglected. Even in the case when this influence should be considered, the treating method is also different from that of bulk forming.（4）．In stamping forming, the restrain action of the die to the blank is not severs as in the case of the bulk forming (such as die forging). In bulk forming, the constraint forming is proceeded by the die with exactly the same shape of the part. Whereas in stamping, in most cases, the blank has a certain degree of freedom, only one surface of the blank contacts with the die. In some extra cases, such as the forming of the blank on thedeforming zone contact with the die. The deformation in these regions are caused and controlled by the die applying an external force to its adjacent area.Due to the characteristics of stamping deformation and mechanics mentioned above, the stamping technique is different form the bulk metal forming:（1）．The importance or the strength and rigidity of the die in stamping forming is less than that in bulk forming because the blank can be formed without applying large pressure per unit area on its surface. Instead, the techniques of the simple die and the pneumatic and hydraulic forming are developed.（2）．Due to the plane stress or simple strain state in comparison with bulk forming, more research on deformation or force and power parameters has been done. Stamping forming can be performed by more reasonable scientific methods. Based on the real time measurement and analysis on the sheet metal properties and stamping parameters, by means of computer and some modern testing apparatus, research on the intellectualized control of stamping process is also in proceeding.（3）．It is shown that there is a close relationship between stamping forming and raw material. The research on the properties of the stamping forming, that is, forming ability and shape stability, has become a key point in stamping technology development, but also enhances the manufacturing technique of iron and steel industry, and provides a reliable foundation for increasing sheet metal quality.3．Categories of stamping formingMany deformation processes can be done by stamping, the basic processes of the stamping can be divided into two kinds: cutting and forming.Cutting is a shearing process that one part of the blank is cut from the other. It mainly includes blanking, punching, trimming, parting and shaving, where punching and blanking are the most widely used. Forming is a process that one part of the blank has some displacement from the other. It mainly includes deep drawing, bending, local forming, bulging, flanging, necking, sizing and spinning.In substance, stamping forming is such that the plastic deformation occurs in thedeformation zone of the stamping blank caused by the external force. The stress state and deformation characteristic of the deformation zone are the basic factors to decide the properties of the stamping forming. Based on the stress state and deformation characteristics of the deformation zone, the forming methods can be divided into several categories with the same forming properties and be studied systematically.The deformation zone in almost all types of stamping forming is in the plane stress state. Usually there is no force or only small force applied on the blank surface. When is assumed that the stress perpendicular to the blank surface equals to zero, two principal stresses perpendicular to each other and act on the blank surface produce the plastic deformation of the material. Due to the small thickness of the blank, it is assumed approximately the two principal stresses distribute uniformly along the thickness direction. Based on this analysis, the stress state and the deformation characteristics of the deformation zone in all kinds of stamping forming can be denoted by the points in the coordinates of the plane principal stresses and the coordinates of the corresponding plane principal strains.4．Raw materials for stamping formingThere are a lot of raw materials used in stamping forming, and the properties of these materials may have large difference. The stamping forming can be succeeded only by determining the stamping method, the forming parameters and the die structures according to the properties and characteristics of the raw materials. The deformation of the blank during stamping forming has been investigated quite thoroughly. The relationships between the material properties decided by the chemistry component and structure of the material and the stamping forming has been established clearly. Not only the proper material can be selected based on the working condition and usage demand, but also the new material can be developed according to the demands of the blank properties during processing the stamping part. This is an important domain in stamping forming research. The research on the material properties for stamping forming is as follows:（1）．Definition of the stamping property of the material.（2）．Method to judge the stamping property of the material, find parameters to express the definitely material property of the stamping forming, establish the relationship between the property parameters and the practical stamping forming, and investigate the testing methods of the property parameters.（3）．Establish the relationship among the chemical component, structure, manufacturing process and stamping property.The raw materials for stamping forming mainly include various metals and nonmetal plate. Sheet metal includes both ferrous and nonferrous metals. Although a lot of sheet metals are used in stamping forming, the most widely used materials are steel, stainless steel, aluminum alloy and various composite metal plates.5．Stamping forming property of sheet metal and its assessing method The stamping forming property of the sheet metal is the adaptation capability of the sheet metal to stamping forming. It has crucial meaning to the investigation of the stamping forming property of the sheet metal. In order to produce stamping forming parts with most scientific, economic and rational stamping forming process and forming parameters, it is necessary to understand clearly the properties of the sheet metal, so as to utilize the potential of the sheet metal fully in the production. On the other hand, to select plate material accurately and rationally in accordance with the characteristics of the shape and dimension of the stamping forming part and its forming technique is also necessary so that a scientific understanding and accurate judgment to the stamping forming properties of the sheet metal may be achieved.There are direct and indirect testing methods to assess the stamping property of the sheet metal.Practicality stamping test is the most direct method to assess stamping forming property of the sheet metal. This test is done exactly in the same condition as actual production by using the practical equipment and dies. Surely, this test result is most reliable. But this kind of assessing method is not comprehensively applicable, and cannot be shared as a commonly used standard between factories.The simulation test is a kind of assessing method that after simplifying and summing up actual stamping forming methods, as well as eliminating many trivial factors, the stamping properties of the sheet metal are assessed, based on simplified axial-symmetric forming method under the same deformation and stress states between the testing plate and the actual forming states. In order to guarantee the reliability and generality of simulation results, a lot of factors are regulated in detail, such as the shape and dimension of tools for test, blank dimension and testing conditions(stamping velocity, lubrication method and blank holding force, etc).Indirect testing method is also called basic testing method its characteristic is to connect analysis and research on fundamental property and principle of the sheet metal during plastic deformation, and with the plastic deformation parameters of the sheet metal in actual stamping forming, and then to establish the relationship between the indirect testing results(indirect testing value) and the actual stamping forming property (forming parameters). Because the shape and dimension of the specimen and the loading pattern of the indirect testing are different from the actual stamping forming, the deformation characteristics and stress states of the indirect test are different from those of the actual one. So, the results obtained form the indirect test are not the stamping forming parameters, but are the fundamental parameters that can be used to represent the stamping forming property of the sheet metal.冲压成形的特点与板材冲压成形性能1．概述冲压是通过模具使板材产生塑性变形而获得成品零件的一次成形工艺方法。
