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奥迪汽车标志注塑模具设计与制造【含全套5张CAD图纸和毕业论文】【优秀资料】

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摘要 ····························································2
前言·····························································3

第一章材料工艺分析
1.1 材料特性···············································4
1.2 模具设计方面需注意·····································4
1.3 注塑工艺条件···········································4
1.4 成型性能···············································4

第二章制品结构及尺寸分析
2.1 制品结构分析···········································5
2.2 制品尺寸精度分析·······································5

第三章模具结构设计
3.1 分型面的选择···········································6
3.2 型腔布局···············································7
3.3 浇注系统的确定·········································8
3.4 注射机的选择···········································12
3.5 模架的选择·············································14
3.6 成型零部件设计·········································15
3.7 推出机构设计···········································17
3.8 排气系统设计···········································18
3.9 冷却系统设计···········································19
附毕业设计小结···········································20
谢辞···················································21
参考文献···············································22

[摘要]

本课题是江苏省普通高等院校模具设计与制造专业，专题综合实践项目之一。是对模具专业学生的一次综合考察。
设计者需通过课题的CAD二维工程图纸，进行模具设计。其中包括：产品材料、工艺、结构、尺寸精度分析，成型零件尺寸计算，合理选择注塑机及标准模架。并用CAD2006完成模具总装图及成型零件图的绘制，完成成型零件的加工工艺卡编写等。
本设计主用软件CAD2006，通过CAD2006完成相关元件的二维工程图纸。并结合Pro/ENGINEER4.0进行辅助设计。经过反复修改，最终完成课题设计。

关键词：模具标准模架 CAD2006

Abstract
This topic is ordinary colleges and universities in Jiangsu Province mold design and manufacturing expertise, special comprehensive practice items.Is to mold a comprehensive survey of students.
Designers have passed the two-dimensional capacitance Block CAD engineering drawings, for mold design.These include: product materials, processes, structure, size precision analysis, forming part size calculation, a reasonable choice and standard mold injection molding machine.And use CAD2006 complete the mold assembly diagram and forming part drawing of the drawing, forming part of the processing technology to complete the preparation of such cards.
The design of the main software CAD2006, with the completion of related components over CAD2006 two-dimensional engineering drawings.Carried out in conjunction with Pro/ENGINEER4.0-aided design.After repeated changes to the final completion of the design issues.

Keywords：Mold Standard Mold CAD2006

前言

模具制造是我国经济建设中的一项重要产业，起着振兴和发展我国模具工业的重要作用，正日益受到人们的重视和关注。“模具是工业生产的基础工艺装备”也已经成为广大业内人士的共识。在电子、汽车、电机、电器、仪器、仪表、家电和通信等产品中，60%～80%的零部件都要依靠模具成形。用模具生产制件,具备高精度、高复杂程度、高一致性、高生产率和低消耗，是其他加工制造方法所不能比拟的。模具又是“效益放大器”，用模具生产的最终产品的价值，往往是模具自身价值的几十倍、上百倍,尤其是在冲压技术相对落后的中国，制造出优质的模具以及生产出高质量的产品势在必行。
经过本次的课题研究主要掌握模具设计的方法及工序，巩固和加深对机械二维、三维的制图能力。设计过程中锻炼查阅文献和资料、自我设计的能力，培养和提升自己的创新能力，增强独立思考问题和解决问题的能力。在对模具设备的结构设计和理论计算上，掌握模具设备的主要结构与性能、工艺适应性与技术参数。从而能根据成型的生产要求、模具结构等因素，经济、有效的使用设备，合理的选择工艺，正确的设计模具，保证成型生产能够经济、合理的进行，提高自身在成型工艺和模具方面的综合着机水平，提高自身解决实际问题的能力。
在这次毕业设计过程中，我得到了袁小江老师的指导，他给了我很多意见和建议，使我的设计更加完善，在此特别的感谢他。同时也感谢那些曾经授课的老师，他们使我学习、获得了专业知识，对设计起了重要作用。也要感谢那些帮过我的同学，他们给我提了很多好的建议。

第一章材料工艺分析

1.1材料特性
ABS无色、无味、呈微黄色。密度为1.02~1.05g/cm³（注射注射级密度为1.05g/cm ³）。具有优越的综合性能：强度高、刚性好，硬度、耐冲击性、制品表面光泽性好，耐磨性好。具有有良的成型加工性，尺寸稳定性好，着色性能、电镀性好。
1.2在模具设计方面需注意：
⑴需要采用较高的料温与模温，浇注系统的流动阻力要小。
⑵注意选择浇口位置，避免浇口与熔接痕位于影响制品外观的部位。
⑶合理设计顶出脱模结构，推出力过大时，制品表面易“发白”、“变混”（顶白）。

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内容简介：: 外文资料翻译系别 XXXXXXX 专业 XXXXX 班级 XXXX 姓名 XXX 学号 XXXXX 指导教师 XXXXXX 2010年4月Compression casting craft and compression casting mold design main pointAbstract: The die-casting machine, the mold and the alloy three, take press the casting as this, among the compression casting craft penetration, their conformity is organically a effective system, causes the die-casting machine and the mold obtains the good match, plays the optimization to press the casting structure, the optimal die-casting machine, the optimization presses the mold design, enhances the craft operating point the flexible role, thus provides the reliable guarantee for the compression casting production.Therefore, the compression casting craft lies within in the mold saying, depth of the connotation is self-evident.Key word: Die-casting machine; Mold; Compression casting craft; The mold designs1.Die-casting machine - mold - alloy systemDie-casting machine, the mold and alloy these three factors, in presses in the casting production process, they constituted a system, namely the die-casting machine - mold - alloy system, it is take presses the casting as this, among the craft penetration, entrusts with the system vigor and the efficiency, but the mold is the craft enters the system the platform.The die-casting machine, the mold and the alloy three relations expressed vividly as shown in Figure 1.The die-casting machine - mold - alloy system main performance is: (1)Ingate position influence backfill metal melt flow direction and the condition, with the backfill die space quality, have the decisive influence to the mold structure and the craft, this is the key is at. (2)Designation best sufficient time, this is extremely important one step, affects to sufficient time metal melt rate of volume flow (Q), also is the sufficient power, according to the above and computation ingate size. (3)Choice exhaust, overflow position and size, except outside normal exhaust, pollution discharge and temperature balance, but also may reduce the impact pressure, avoids the metal splashing and producing the burr.(4) Heating and cooling, balanced mold temperature, maintenance operating temperature.2.Compression casting crafts and the mold design key technologies When compression casting the ingate position influence presses the casting the structural design, the quality and the compression casting mold design, may obtain the correct establishment ingate position prompt through the inquiry material.As a result of the casting structure multiplicity, must choose the ingate the correct position is very difficult, but also has some basic requests, like thought generally the establishment ingate must cause sufficient when the metallic jet has as far as possible compared the long distance by the open jet in the die space average, also is the correct ingate position, the shape, the size (flows to angle) to coordinate the compression casting parameter to be possible to obtain the metallic jet to expand along the wall unceasing order, to change, and continuously expands to the terminus.The die space majority (i.e. branch die space) completes by the jet flow backfill, only then a small part of die space (i.e. non-branch die space) by the metal melt branch supplemented completes or collides by the metal melt stock class completes the backfill, and overflows the system elimination vestiges through the platoon.Figure 2 is in the pouring position and branch die space schematic drawing 1”.The identical pressure casting choice different ingate position and flows to the angle, when may obtain the area percentage which the different branch die space, the non-branch die space and hold respectively, Figure 2 the shell compression casting, because the ingate position is different, obtains the different branch die space and the non-branch die space.The chart 2a ingate is vertical to one side wall, because the components crown long square edged orifice separates two sidewalls, the result is only then one side for the branch die space; Must fill another one side wall, must pass through the running channel both sides attachment point, the final two liquid flow gathering completes the packing, this part is the non-branch die space.Because the branch die space accounts for the area percentage not to be high, therefore can produce the massive waste products, like chart 2a1.In chart 2b, the ingate position does not make the change, only is wall thickness and so on crown rectangle Kong Yong craft muscles connects, like this fills when the metal melt changes, fills another one side wall along the muscle board, caused two sidewalls both to become the branch die space, increased the branch die space to account for the percentage, the casting quality also large scale enhances, like chart 2b1.In chart 2c, the components and chart 2a are same, the crown square edged orifice does not add the craft muscle, but establishes the ingate in a components end, such metal melt simultaneously carries on the backfill from two sidewalls, thus expanded the branch die space percentage, had guaranteed the quality, enhanced the qualified rate.This is the identical components three kind of ingate establishment plan, the proof ingate position crucial nature. Although the computer technology is helpful to the designation ingate position, but the computer technology is only one method, but the ingate position design did not lose was still a key technologies.Between 3 compression casting craftmain point 3.1 metal pressures, the speed and the current capacity relationsIn the principle the die-casting machine are a liquid metal pump, it transports under the pressure the metal melt to the compression casting model cavity in.The pump characteristic is transports the power (rate of volume flow), is the pressure function, this aspect as early as in the 70s, first makes the valuable development work by Australian Asia CSIRO, has established a useful tool with the pQ2 chart, according to the casting i.e. mold request, decided the machine the adjustment value, is originally uses in the hot cell die-casting machine the zinc base alloy pressing in the casting, but very quick expands to Leng Shiji on.In principle, now the pressure and the rate of volume flow relations which knew very well from the hydromechanics principle, shifts to the die-casting machine practical application.The metal pressure is higher, is also quicker in the spray nozzle and the ingate place metal melt flow rate, but also must consider victory flow resistance which as a result of the flowing section change, the direction change and the wall roughness existence produces, xi expresses sum of the these resistance with the friction coefficient.If the known immeasurable steel coefficient xi, may calculate the metal pressure which certain ingate speed needs, according to the compression casting alloy and the casting request, the ingate speed has an empirical value, should observe, see Table 1, therefore needs the die-casting machine to provide the corresponding speed.Table 1 ingate speed selectionTable 1 Choice of velocity at ingateProjectA1MgCuZna(m.s-1)25-6040-9030-4530-50The low value uses in the relatively thick casting, the high value uses in the relatively thin casting, common magnesium alloy casting ingate speed compared to aluminum high25%. Time the vacuum die casting ingate speed is 15-30m/s.3.2 Take the casting as this, optimizes the die-casting machine - mold - alloy system, enhances the craft flexibility In the die-casting machine - mold - alloy system, through the adjustment craft parameter, may improve presses the casting the quality and the performance.These craft parameter defined with work window (OW).This indicated OW is these craft parameter limit chart.In the compression casting craft, the sufficient time, the ingate speed and the final metal static pressure use to define OW, these parameters and sufficient phenomenon related, relies on in the mold design and the die-casting machine performance.Designs when the mold, in OW all spots were considered all is equal, and does not have the priority, may think the best operating point exists in OW unknown lights, in presses the mold installs on the die-casting machine in front of the experimental mold is unable to find it.In the mold design stage guaranteed easy to find the good operating point is based on the flexible consideration, the flexibility is obtains in OW through the adjustment.Therefore, divides into the craft parameter the soft parameter and the hard parameter two kinds, the soft parameter is refers through the operation or a control device carries on the adjustment the parameter, like parameters and so on power level, metal pressure, melt temperature, mold temperature and cycle time.The die-casting machine which the hard parameter is refers to which one kind to have to revise the mold or simultaneously must revise, like drift diameter, ingate area, air discharge duct and so on.Soft parameter when experimental mold easy to change and to obtain successfully, the hard parameter changes then both the difficulty and costs a great deal of money, time-consuming, needs to disassemble the mold frequently in order to revise.Therefore, the optimized method is and expands the OW internal assignment integral point based on the soft parameter the flexibility, thus provides the great scope for the mold experiment, avoids the time-consuming expensive mold change.3.3 shoots the curve from the pressure to mentionNow die-casting machine Chang Peiyi three level of compression casting systems: The level advances gradually for the drift idling speed, pushes the metal melt to the ingate, namely the so-called slow pressure shoots the stage; The second level is the drift by high speed the metal melt through the ingate, fills the die space in the stipulation time, namely sufficient stage; The third level for the casting which not yet completely coagulates under the high pressure (starts pressure intensifier) to carry on the coagulation and by the compaction, namely compaction stage.Shown in Figure 17 for the model three levels of pressures shoots the curve schematic drawing, attempts the curvature to divide into the level slow pressure to shoot, two levels sufficient and three level of turbo-charged compaction three stages.Some pressures shoot the system to shoot the level pressure divide into two small parts, the first part is the drift seals up the pouring material mouth (shown in Figure 18 the X1 line) first, the second part shoots the stage for the slow pressure, then carries on the light again and the compaction, this became four levels of pressures to shoot the system, like this except might avoid the melt splashing the pouring material mouth, might raise the compression chamber initial fullness.3.3.1. Slow pressures shoot the stageSlow pressure to shoot the stage mainly are elect in the craft to control the slow pressure to shoot the speed, the goal are wells up when the metal melt to the ingate, presses in the room the gas to be able completely from the runner to enter the die space, but by the metal melt package, does not avoid in the casting forming the blowhole; Therefore, needs to choose a critical drift speed, may be the constant acceleration, also may be the constant speed, said generally, the constant acceleration effect is good.The overseas die-casting machine matches by “Parashot or “SIMUI” the constant acceleration slow pressure shoots the speed elects to control the system, Figure 19, chart 202 may take elects to control the slow pressure to shoot reference the speed.3.3.2. Sufficient stages This stage most should pay attention in the craft: The sufficient time, the pressure shoot the speed, the ingate speed and the air pressure shoot the speed the reciprocity, and mainly wants the parameter the choice.Best sufficient time The sufficient time is the metal melt has flowed the ingate, by the high ingate speed, fills the die space before the metal melt stop flowing the time.This time is very short, is an extremely essential parameter, selects the die-casting machine, carries on foundation which the technological design and the mold design.The sufficient time must be short, the goal is sufficient when does not have the early time in the casting smallest spot or the liquid flow far-end to coagulate, avoids the casting appearing lacks flaws and so on meat, cold shot.The sufficient time is shorter, the sufficient speed is higher, can enlarge the die space to wear, but but also possible to splash because of zhang the metal and to produce the edge; The sufficient speed is high, can enable in the die space the gas not to have the enough time to transgress from the die space.The sufficient time correct choice only then the overall evaluation can obtain, Table 3 gave has chosen the sufficient time and ingate speed correlation factor 4.The metal melt had decided from the operating temperature to the temperature of solidification release quantity of heat it maintains the castability under the same thermal conductivity time, therefore this kind of thermal then achievement determines its may imitate the time criterion most greatly.The release quantity of heat and the sufficient time are proportional, compared to may obtain several kind of alloy sufficient time relations according to the quantity of heat.The Mg alloy, the Zn alloy, the A1 alloy and the Cu alloy under the same coagulation condition, from the operating temperature to the temperature of solidification release quantity of heat respectively are 261, 329, 509, 918kCal/dm3, then they the time ratio is Mg: Zn: AI: Cu 0.51: 0.65:1:1.8.In other words, Mg=: 0.51AI, Zn=0.65AI, Cu=1.8AI.When compression casting obvious molten metal in die space not superheat, the people observe the melt to flow have certain quantity solid phase, when the solid phase rate achieved30%-80%, In the die space the bath movement only can through the high rate of inflow, when best sufficient time according to type (17) computation, quite Yu Fzhi is70%-80%.The best sufficient time speaking of each kind of magnesium alloy shoots when the pressure must the aluminum alloy be quicker than at least 2 times, the copper alloy best sufficient time and the alloy composition element related, the leaded brass (CuZn37Pb) and the magnesium alloy is close, the silicon brass (CuZnl5Si4) and the aluminum alloy is close.The casting surface quality quantity increases along with the sufficient time changes, the sufficient time is short, the pressure shoots the power to be big, sufficient is quick, but because of the ingate thickness limit, the excessively short sufficient time causes the casting the factor of porosity increase.Figure 22 is the sufficient time presses the casting quality to the aluminum influence 7.Chart 233,8 is one kind which the recent years proposed to the aluminum, the magnesium presses the casting wall thickness and the sufficient time relations relational graph.The superficial quality requests to choose the short sufficient time high. Pressure shoots the speed, the sufficient speed and the air pressure shoots the speed.(1) Pressure shoots the speed (drift speed)The pressure to shoot the speed (drift speed) is in the sufficient stage unit time drift displacement.In traveling schedule curve sufficient stage no matter what chooses two spots, the survey traveling schedule distance and the sufficient time, then obtain the pressure to shoot the speed = survey the distance (mm)/pressure to shoot time (ms). (2)Sufficient speed (ingate speed)The sufficient speed is the ingate speed, concerns with the drift speed and the drift area.In presses in the room - - mold this loop system, take the sufficient time metal passes the ingate rate of volume flow Q as the foundation.Only then after designated generally the die-casting machine, can determine the drift area, the ingate speed may according to Table 1 selection.The ingate speed is the important parameter, has the important influence to the casting quality and the mold life.The ingate speed excessively is high can increase the die space surface because corrodes, sticks the probability which the mold receives damages; Although the low ingate speed is advantageous in the gas discharges from in vivo, but also can cause the casting mechanics performance and the surface quality goes bad.The casting volume flaw often appears by the uniform distribution micro hole or by the big hole in the casting, high ingate speed compression casting strength ratio low ingate speed low, is helpful in forms the micro hole in the casting, causes the casting surface to be brighter and cleaner, the organization is more compact.Ingate speed and casting wall thickness related, but decided by the ingate thickness, the actual same wall thickness casting, possibly has the different thickness ingate, from this also can use the different ingate speed to come the compression casting.But has to ingate structure experience graph 2, confirmed the ingate structure and the ingate speed, when to casting quality influence, recommendation fine casting operating point region thin-walled casting, in choice neighbor chart grid area.Obviously, when very thin ingate, because the ingate parameter is the low value, the need higher ingate speed.Sufficient time drift speed o excessively high, besides to mold life and casting quality influential, but also can because the sufficient end time drift impact function, has caused to move, to decide the mold to push, when is pushed the slit to surpass 0.05-0.15 mm, but also can produce the molten metal the phenomenon which splashes from the mold comes out.Sufficient time ingate speed a with casting wall thickness and metal melt in die space flow length related, as shown in Figure 27.(3) Biggest air pressure shoots the speedBiggest air pressure to shoot speed ot max is presses in the room not to have in the situation which the metal also the governor valve all start, in unit time drift displacement.It is the cold room die-casting machine important technical parameter, to has the metal sufficient time drift speed 0, in the running channel speed a and presses the casting quality to have the important influence.(a) Compression casting machine-pressed shoots the power which the system can provideFor in the short sufficient time introverted die space to fill the large capacity metal melt, needs the high drift speed and in the running channel speed, this must entrust with the die-casting machine high biggest air pressure to shoot the speed.The modern Europe die-casting machine biggest air pressure shoots the speed to achieve 11m/s, Japan recent years also appeared 10m/s the supervelocity die-casting machine.(b) Air pressure shoots the speedAir pressure to shoot the speed is the die-casting machine adjustable parameter.Because presses the room - die space system resistance the existence, the sufficient time drift speed always shoots the speed the air pressure to be much smaller than.May know by chart 304, when certain in running channel area ot max increases from 4m/s to 8m/s, but the sufficient time drift speed o enhances from 2.4m/s (I) to 3.1 m/s(II), does not look like ot max such to enhance 1 time.Theoretically, when the pressure shoots the output is biggest 02/ ot max2=Q2/Q at max2=1/3, then 0/ot max2=Q/Qot max=0.577, as shown in Figure 31.Then0=0.577 upsilon ot max. The cold-press room die-casting machine must have the high level most greatly spatialPressure to shoot the speed, like this may improve the craft operating point spiriactiveness.The graphic solution may help us to choose the die-casting machine, supposes counts the compression casting mold, and enhances the craft flexibility, thus proposeshe high craft success ratio.3.3.3 Compaction stages(1) From the pressure curve looked the pressure shoots when pressureChart 362 shows machine-pressed for the compression casting shoots in the cylinder the pressure curve.The figure shows, the compression casting process pressure has approximately the sufficient pressure, the final pressure (two levels of pressures shoot when was equal to accumulator pressure, three levels of pressures shoot when has added on increase of pressure), but also has is the sufficient conclusion, the piston speed the impact pressure which produces for the zero hour (Impact Pressure).The impact pressure peak instantaneous replies the accumulator pressure.The compaction pressure is refers to the pressure to shoot of (actuation) the cylinder intrinsic pressure to shoot (actuation) the pressure (accumulator pressure) after the supercharge pressure superimposition, is multiplied by the pressure to shoot ratio of the piston area and the drift area, or is multiplied by the pressure to shoot ratio of piston diameter and the drift diameter square.Pressure intensifier principle like chart 372 shows.Big area (Ap) piston (dp) is connected with small area (Aa) piston (ds), the big piston (primary piston) on withstands pressure p1, after impels the valve piston (secondary piston) pressurize p2 P2 and the pressure shoots the cylinder the pressure superimposition pressure to be called working pressure pe, is multiplied by the pressure to shoot piston area A1 and drift area ratio of A0 (A1/A0), after or is multiplied by the pressure to shoot piston diameter d1 and drift diameter d0 ratio of square (d1/d0)2 is called the compaction pressure PkCommon die-casting machine supercharger pressure transformer ratio is 1:3 or 1:2.(2)Affects the casting factor of porosity the factorDrift infliction to be possible to carry in the metal melt pressure makes up shrinks and compresses the gas hole.The metal pressure and factor of porosity relations as shown in Figure 39 3.The pressure and the factor of porosity are not the linear relations, therefore, obtains the high pressure cannot eliminate the hole completely.Although hole minification, but still existed in the casting, this was not big with the alloy type relations, perhaps coagulated the scope width the alloy hole easily to gather, but this did not mean, the alloy and the increase element were unimportant, they affected the hole the formation and the distribution condition, and remarkable influence performance.Makes up shrinks with compresses the hole the pressure to have to transmit the metal which coagulates, this to the cold-press room die-casting machine and the hot cell die-casting machine all is a fact.Once in the metal melt pouring person cold-press room compression casting machine-pressed room, the metal melt contacts presses the room base to start to coagulate, some drift strength must use for to fold these cold skins, presses the metal which in the room the pouring enters to be less, this kind of phenomenon is more serious.When the material cake is thin, can increase the hole.Like chart 407 shows is material cake thickness and the factor of porosity relations.Common material cake thickness is approximately 20mm, the chart 417 showing presses the room fill to the die space in the metal pressure influence, presses the room fullness is35%, The casting is coagulates under 4664MPa, the decompression chamber fullness produces the massive pre-coagulation metal to enter the die space, they can cause the jamming to hinder the pressure effective transmission, will increase the unusual organization inevitably, will be the casting production latent weak link.In the compaction stage, the use turbo-charged reduces the casting hole, relies on has the full long time maintenance liquid state in running channel.The formula (31) is uses in the computation the running channel coagulation time, in fact is formula (17) f=1 (i.e. solid phase score is 100/100) the time distortion.t=t1-ts; a is in running channel thickness; p is during the solid liquid state the alloy density mean value; Hsw is the alloy melting heat; c is congeals firmly condition the temperature; tL is the alloy liquid phase temperature; ts is the alloy solid phase temperature; tF is in nearby the running channel the mold temperature; F is the mold material thermal conductivity; CF is the mold heat capacity; PF is the mold material density.Table 9 is according to type (31) and Table 5, Table 6 computation obtained in running channel thickness with in running channel coagulation time, most lunar month with twenty-nine days presses the time and the pressure shoots the system related, regarding has the pressure intensifier pressure to shoot the system, this value is 0.05-0.03s, if the aluminum, the magnesium alloy mold heat for 250.The copper alloy mold heats for 400 this place, regarding in running channel nearby by exiles metal melt and the high velocity, causes the temperature increment, thus retarded in the running channel coagulation time, Figure 42 131 for in running channel thickness and the coagulation time relations.Therefore, was equal to has enlarged Table 9 in running channel thickness, regarding the aluminum, the magnesium alloy enlarges 1-1.2mm, is bigger than 1.6mm to the copper alloy.The compression casting machine-pressed shoots the system turbo-charged to construct presses the time to be possible according to need to carry on the adjustment, as shown in Figure 43, adjustable is: (a) instant turbo-charged; (b) slow turbo-charged; (c) retards turbo-charged.The high mold and the alloy temperature, may lengthen the supercharging the validity.The direct compression survey proof, the transmission pressure time shows consistently with chart 447.The drift exerts pressure always maintains to the casting coagulation is very important, specially to the hot cell die-casting machine, too short holds presses the time to be able to produce the big hole.But still assumed fusing the alloy even to be able when the drift return trip by resorption.To the hot cell die-casting machine, must consider the drift creeping motion.This is fills completely after the die space, the drift continual motion causes the metal melt to cause through the drift link transgression.If the drift hits the pouring pot bottom directly, then loses the complete metal pressure, can initiate the multi-holes the casting.The pouring pot bottom should have the 20mm high metal melt at least to use in the drift creeping motion.When the casting thick wall and the thin wall with save, after the thin wall condensation could be cut off the thick section pressure transmission, the hole develops in among, controls the mold to cool, achieved the moderate gradient of temperature, might reduce this question.But the request section difference do not have to surpass 1.5 times, otherwise on difficult to obtain the very good compensation.The seal lug boss (boss) place easy to appear the hole, besides enhancement cooling, the available pressure sells exerts pressure reduces the hole.Coagulates when the lug boss, will sell by the hydraulic pressure pushes in the die space, will carry on partial makes up shrinks and extrudes the hole.Shown in Figure 45 for the pressure sells pushes in the time and the porosity relations.This means key lies in the extrusion time which the control pressure sells, the time prematurely, the casting or the liquid state, do not play the extrusion role; The time too is late, then the casting coagulated, the pressure sells pushes in with difficulty, also does not get up the compressibility effect.Shown in Figure 46 the cylinder cover to cover is a typical example which the application pressure sells.3.4 Temperature parameters The temperature is the compression casting process hot condition manifests specifically, has the vital significance to the casting inside and outside quality and the mold life.This only involves the alloy temperature and the mold temperature.3.4.1 Alloy temperatureMetal pouring temperature speaking of all compression casting alloy, all should have moderately superheat, in order to avoid pouring temperature and the mold difference of oversized, causes the mold temperature alternation load to be intense, has the thermal load to affect the mold life.Moreover the degree of superheat is big, also can affect the alloy quality.Table 102 introduced the alloy temperature of fusion and the pouring temperature scope, may see time the alloy casting the degree of superheat.After the alloy melt pouring person presses the room, starts to cool immediately, and in presses in the room along with the alloy the resident time and presses the room fullness to change, as shown in Figure Mold temperatures The mold temperature is one of important craft parameters, may say correct, the constant mold temperature is high quality and the reliable production, the high productivity, the low rejection rate and the long mold life basic premise. In front of the compression casting first wants the preheating mold, enables the mold warm to achieve 150200, like this is advantageous to the painting coating, reduces melt temperature drop and the extension melt flow, is advantageous in the die space backfill, moreover the mold preheating also can enhance the mold material toughness and the reduced die space surface thermal shock.The mold preheating best means use the hot oil heating, provides with the aid of Yu Muwen machine circulates the hot oil and carries on the mold warm control.If the machine attaches loads and unloads the mold fast the installment, may before the installment the mold first preheating good, like this may save on the machine the mold preheat interval, speeds up the machine to start.Simultaneously the mold warm machine also has the circulating cooling aqueous system, carries on essential cooling to the mold.The gas heating also is one means, regards the factory condition to be possible to use the natural gas or the coal gas, in this situation, mold temperature available surface thermometer and temperature measurement pen survey.Other heating method also has the electricity, the far infrared heating.Table 112 is the recommendation mold temperature, all do not have to surpass in the table in preheating or the work the maximum.3.4.3Hot cell compression casting machine-pressed ingot metal fluid temperature Selects the hot cell die-casting machine compression casting the molten metal temperature: AM60B alloy, 640; AZ91D alloy, 630; AM50A alloy, 650; Zn alloy, 430. Is higher than the above temperature, all cannot use the hot cell machine compression casting, like ZAl2, ZA27 and AE, AS magnesium alloy and so on.Because is higher than this temperature, the molten metal meets the corrosion (solution attack) the pouring pot. In the compression casting process, must guarantee spray nozzle (body) temperature, when heating does not surpass the above molten metal the temperature.But molten metal if is lower than this temperature, when drift return trip, in the spray nozzle metal energy flow does not return to in the pouring pot, then the drift pressure shoots the traveling schedule to be able to change, affects presses the casting quality, serious when can be unable to work.压铸工艺及压铸模具设计要点摘要：压铸机、模具与合金三者，以压铸件为本，压铸工艺贯穿其中，有机地将它们整合为一个有效的系统，使压铸机与模具得到良好的匹配，起到优化压铸件结构，优选压铸机、优化压铸模设计、提高工艺工作点的灵活性的作用，从而为压铸生产提供可靠保证。所以，压铸工艺寓于模具中之说，内涵之深不言而喻。关键词：压铸机；模具；压铸工艺；模具设计1 压铸机模具合金系统压铸机、模具和合金这三个因素，在压铸件生产过程中，它们构成了一个系统，即压铸机-模具合金系统，它是以压铸件为本，工艺贯穿其中，赋予系统活力与效率，而模具则是工艺进入系统的平台。压铸机、模具与合金三者关系形象地表示如图1所示。压铸机-模具-合金系统主要表现为： (1) 内浇口的位置影响充填金属熔体的流动方向及状态，和充填型腔的质量，对模具结构和工艺产生决定性影响，这是关键所在。 (2) 选定最佳充型时间，这是非常重要的一步，影响到充型时的金属熔体的体积流量(Q)，也就是充型功率，并据此计算内浇口尺寸。 (3) 选择排气、溢流的位置和尺寸，除正常的排气、排污和温度平衡外，还可减少冲击压力，避免金属飞溅和产生毛刺。(4) 加热与冷却，平衡模具温度，保持工作温度。2 压铸工艺与模具设计的关键技术压铸时内浇口的位置影响压铸件的结构设计、质量和压铸模具设计，通过查询资料可得到正确设置内浇口位置的提示。由于铸件结构的多样性，要选择内浇口的正确位置是很困难的，但也有一些基本要求，如普遍认为设置内浇口要使充型时的金属射流尽可能地以自由射流在型腔中流过较长距离，也就是正确的内浇口位置、形状、尺寸(流向角)配合压铸参数可获得金属射流沿型壁不断有序扩展、转向，并连续不断地扩展至尽头。型腔的大部分(即主干型腔)由射流充填完成，只有一小部分型腔(即非主干型腔)由金属熔体支流补充完成或由金属熔体股流相碰撞完成充填，并通过排溢系统排除残余。图2为内浇位置与主干型腔示意图1”。同一个压铸件选择不同的内浇口位置和流向角，可以得到不同的主干型腔、非主干型腔和各自占有的面积百分数，图2中的壳体压铸时，由于内浇口的位置不同，得出不同的主干型腔和非主干型腔。图2a内浇口垂直于一侧壁，由于零件顶部的长方孔把两侧壁分开，结果是只有一侧为主干型腔；要充填另一侧壁，必须经浇道两端连接处，最后两股液流汇聚完成填充，这一部分就是非主干型腔。因主干型腔所占面积百分比不高，因此会产生大量废品，如图2a1。在图2b中，内浇口位置不作改变，只是把顶部长方孔用等壁厚的工艺筋连接起来，这样充填时金属熔体转向，沿筋板充填另一侧壁，使两侧壁都成了主干型腔，增大了主干型腔所占百分比，铸件质量也大幅度提高，如图2b1。在图2c中，零件与图2a相同，顶部方孔不加工艺筋，但将内浇口设置在零件一端，这样金属熔体从两侧壁同时进行充填，从而扩大了主干型腔百分比，保证了质量，提高了合格率。这是同一零件三种内浇口设置方案，证明内浇口位置的关键性。虽然计算机技术有助于选定内浇口位置，但计算机技术仅是一种方法，而内浇口位置设计仍不失为一项关键技术。3 压铸工艺要点3.1 金属压力、速度和流量之间的关系在原理上压铸机是一台液态金属泵，它在压力下将金属熔体输送到压铸模型腔内。泵的特性是输送功率(体积流量)，是压力的函数，这方面早在70年代，首先由澳大亚CSIRO做出有价值的开发工作，用pQ2图建立了一个有用的工具，根据铸件亦即模具的要求，决定机器的调整值，本来是用于热室压铸机的锌合金压铸件上，但很快就扩展到冷室机上。在原则上，现在从流体力学原理所熟知的压力与体积流量的关系，转移到压铸机的实际应用。金属压力愈高，在喷嘴及内浇口处的金属熔体的流动速度也愈快，但也必须考虑克服由于流动截面变化、方向改变和型壁粗糙度存在而产生的流动阻力，用阻力系数来表示这些阻力之和。如果已知无量钢系数，就可以计算出一定内浇口速度所需的金属压力，根据压铸合金和铸件要求，内浇口速度有一经验值，应该遵守，见表1，因此需要压铸机提供相应的速度。表1 内浇口速度的选取Table 1 Choice of velocity at ingate项目A1MgCuZna(m.s-1)25-6040-9030-4530-50低值用于相对厚的铸件，高值用于相对薄的铸件，一般镁合金铸件的内浇口速度比铝的高25%，真空压铸时的内浇口速度为15-30m/s。3.2 以铸件为本，优化压铸机模具合金系统，提高工艺灵活性在压铸机模具合金系统中，通过调整工艺参数，可以改善压铸件的质量和性能。这些工艺参数用一个工作窗口(OW)加以限定。这说明OW是这些工艺参数的极限图。在压铸工艺中，充型时间、内浇口速度和最终金属静压用以限定OW，这些参数与充型现象有关，依赖于模具设计和压铸机性能。在模具设计时，OW内的所有点被认为都是相等的，并无优先权，可以认为最佳工作点存在于OW内的未知点上，在压铸模装在压铸机上试模之前是无法找到它的。在模具设计阶段保证易于找到良好工作点是基于灵活性的考虑，灵活性是在OW内通过调节获得的。为此，将工艺参数分成软参数和硬参数两种，软参数是指通过操作或一个控制装置进行调节的参数，如功率水平、金属压力、熔体温度、模具温度和循环时间等参数。硬参数是指一种需修正的模具或同时需修正的压铸机，如冲头直径、内浇口面积、排气槽等。软参数在试模时容易更改并获得成功，硬参数更改起来则既困难又费钱、费时，常常需要拆卸模具以便重新修正。因此，优化手段是基于软参数并扩大OW内调整点的灵活性，从而为模具试验提供较大的范围，避免费时费钱的模具更改。3.3 从压射曲线说起当今压铸机常配以三级压铸系统：第一级为冲头慢速渐进，将金属熔体推至内浇口，即所谓慢压射阶段；第二级是冲头以高速将金属熔体通过内浇口，在规定的时间内充满型腔，即充型阶段；第三级为尚未完全凝固的铸件在高压下(启动增压器)进行凝固和被压实，即压实阶段。图17所示为典型的三级压射曲线示意图，图中曲线分成一级慢压射、二级充型和三级增压压实三个阶段。有些压射系统将第一级压射又分成两个小部分，第一部分是冲头先封住浇料口(图18所示X1线)，第二部分为慢压射阶段，然后再进行光型和压实，这就成了四级压射系统，这样除了可避免熔体溅出浇料口，更可以提高压室初始充满度。3.3.1 慢压射阶段慢压射阶段在工艺上主要是选控慢压射速度，目的是在金属熔体涌至内浇口时，压室中的气体能完全从浇口进入型腔，而不被金属熔体包裹，避免在铸件中形成气孔；为此，需要选择一个临界冲头速度，可以是等加速度，也可以是恒速，一般说，等加速度效果好。国外压铸机多配以“Parashot或“SIMUI”的等加速度的慢压射的速度选控系统，图19、图202可作为选控慢压射速度之参考。3.3.2 充型阶段此阶段在工艺上最应关注的是：充型时间、压射速度、内浇口速度和空压射速度的相互关系，及主要要参数的选择。最佳充型时间充型时间就是金属熔体流过内浇口，以高的内浇口速度，在金属熔体停止流动前充满型腔的时间。这一时间很短，是一个非常关键的参数，是选用压铸机，进行工艺设计和模具设计的基础。充型时间要短，目的是充型时在铸件最小的部位或液流远端不产生早期凝固，避免铸件出现缺肉、冷隔等缺陷。充型时间越短，充型速度就越高，会加大型腔磨损，还可能因胀型而金属飞溅和产生飞边；充型速度高，会使型腔中气体没有足够时间从型腔中逸出。充型时间的正确选择只有综合考虑才能得到，表3给出了选择充型时间和内浇口速度的相关因素4。金属熔体从工作温度到凝固温度释放的热量决定了其在相同导热率下保持可铸性的时间，因此这种热量便作为判定其最大可充型时间的尺度。释放热量与充型时间成正比，根据热量比可以得到几种合金的充型时间的关系。Mg合金、Zn合金、A1合金和Cu合金在相同凝固条件下，从工作温度到凝固温度释放的热量分别为261、329、509、918kCal/dm3，则它们的型时间比为Mg:Zn:AI:Cu 0.51:0.65:1:1.8。也就是说Mg=:0.51AI，Zn=0.65AI，Cu=1.8AI。压铸时显然金属液在型腔中无过热，人们观察到熔体流中具有一定数量的固相，当固相率达到30%80%时，在型腔中熔体运动只能通过高的流入速度，当最佳充型时间按式（17）计算时，相当于f值为70%80%。最佳充型时间对各种镁合金而言在压射时至少要比铝合金快2倍，铜合金最佳充型时间与合金组成元素有关，铅黄铜（CuZn37Pb）与镁合金相近，硅黄铜（CuZnl5Si4）与铝合金相近。铸件表面品质量随充型时间增加而变化，充型时间短，压射功率大，充型快，但因内浇口厚度的限制，过短的充型时间使铸件的孔隙率增加。图22是充型时间对铝压铸件品质的影响7。图233,8是近年提出的一种对铝、镁压铸件壁厚与充型时间关系的关系图。表面品质要求高的就选较短的充型时间。压射速度、充型速度和空压射速度。 (1) 压射速度(冲头速度)压射速度(冲头速度)是充型阶段单位时间内的冲头位移。在行程曲线充型阶

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