复合高速机刀具结构的设计与制造外文文献翻译/中英文翻译/外文翻译_第1页
复合高速机刀具结构的设计与制造外文文献翻译/中英文翻译/外文翻译_第2页
复合高速机刀具结构的设计与制造外文文献翻译/中英文翻译/外文翻译_第3页
复合高速机刀具结构的设计与制造外文文献翻译/中英文翻译/外文翻译_第4页
复合高速机刀具结构的设计与制造外文文献翻译/中英文翻译/外文翻译_第5页
已阅读5页,还剩9页未读 继续免费阅读

付费下载

下载本文档

版权说明:本文档由用户提供并上传,收益归属内容提供方,若内容存在侵权,请进行举报或认领

文档简介

                              外文翻译   专        业      机械设计制造及自动化    学  生  姓  名          张  金  浩            班        级        BD 机制 042          学        号        0420110233           指  导  教  师          惠  学  芹              1 外文资料名称: Design and manufacture of      composite high speed machinetool structures           外文资料出处: Composites Science and                       technology           附         件:  1.外文资料翻译译文               2.外文原文                         指导教师评语:                     签名:                                                           年     月     日    2 复合高速机刀具结构的设计与制造  Dai Gi lLee,Jung Do Suh, Hak Sung Kim, Jong Min Kim 摘要  高传输速度,以及高切削速度机床重要的是生产力的提高。在制作模具时非加工时间,被称为空中交织的时间。在数量以 70 的总加工时间与形状复杂的产品,其中一个最主要的原因是生产率低,还有就是大型大众性的运动部件的机床,其中不能负担快的加速和减速过程中遇到的操作。 此外,机床振动结构是其他原因限制。在这篇文章中,高速数控铣床的设计与纤维增强复合材料克服了这种局限性。纵向和横向的大型数控机床制造加入高含量碳纤维环氧复合材料,用粘合剂和螺栓钢筋焊接结构。这些复合材料结构减少纵向和横向的重量,从 34 到 26  ,增加了阻尼。不需要有太大调整,这台机器上采用了精度定位。  1.导言  数控铣床和加工中心应用于制作各种模具即用于家电,汽车内饰,  冲压和注塑成型。正常加工的机床,其切削工具提出了名义利用率。而价格切换至快速导线模式转移期间切削工具,如果没有接触工件:时间用于传输一 个刀具至工件,是所谓的空切时间。一般来说,只有大约 30 的总加工时间是花费在实际切削,而其余的 70  是花在空切时间。因此,不仅要具有高的切削速度,而且具有较高的传输速度,是取得资源增值加工的必不可少的条件。在全球竞争机床市场,虽然切割速度的提高是由于新的切削刀具材料的研制,如陶瓷,立方氮化硼,金刚石等,但是生产力仍受制于低转移向高速大规模方向移动。传统的钢标架最高加工速度为 0.2 0.8米 /秒,  最大加速度 0.2-2.1m/s(常规加工中心, mynx400/ace-tc320d,大宇重工机械有限公司,韩国)。然而,  现代高速铣床须有最大加速度 14 m/s和速度。这些高传输速度,是难以实现如果庞大的钢铁架利用。  此外,机床结构振动形成问题,在制造过程中,在这些高的速度,很可能导致质量低劣产品的相对位置误差在 3-5之间。最近机床都要求有一直被精度定位的,特别是密切相关的精密产品。为保证高速运行的准确性,机床结构设计应具有不消耗刚度和阻尼性能,  但这是相互矛盾的要求,如果常规金属材料是受雇于常规金属,那么几乎具有相同的低比刚度的同低阻尼特性。机床结构高刚度和高阻尼要求,以增加他们的基本自然频率并减少引起的 振动。高刚度高阻尼的机床结构能满足用人纤维增强聚合物复合材料。增强纤维复合材料构成的加固纤维具有很高的具体刚度和矩阵高阻尼,由此产生的材料复合特性反映最佳的特点,即高 3 比刚度、高阻尼。此外,夹层结构,其面结构制成的纤维增强复合材料、其核心材料制成的蜂窝状或发泡结构,最大限度地发挥优势的时候,他们适用于抵抗弯矩的结构。  因此,夹层结构和复合材料我们已使用的越来越多,在宇宙飞船飞机,汽车零部件,机器人手臂  ,甚至机床  。  变形的机床结构下的切削力和结构惯性负载启动过程并停止生产的情况,不仅影响产品质量,而且有很强 噪音和振动。然而,这增加了一般的机床结构,因此需要大量电动机,轴承和运动指导体系。因此,  最好的方法,就是提高机床结构的刚度,没有大大增加部件的结构,如复合材料夹层结构。  在这项研究中,纵向和横向的高速数控铣床的设计及制造所用复合材料夹层结构是胶接,以焊接钢管结构 - 一种混合机床结构。垂直柱的横向滑动及制造与复合材料夹层结构,而横栏的垂直滑动钢筋与高模量复合板。该混合结构设计成具有等效结构刚度的常规钢结构,这是按经典梁理论分析的。此时,自然频率和阻尼能力以及减轻重量的复合材料混联机床结构测定和相对于常 规钢机床结构。  2.设计混联机床结构  2.1特色的混合型梁  抗弯刚度简支夹心束所示图。                    (1) 如 s模面和核心。偏转长简支持夹层梁下的集中载荷 P基于简单梁理论是指用 D1的原因弯曲变形和 D2由于剪切变形 15,16 凡与 GC代表等效截面面积和剪切模芯材料,分别由于夹层结构具有较低的核心剪切刚度,  简单梁理论,由于忽略剪切变形,因此可能不会作出准确的结果。因此,在计算结果刚度的夹层梁标本相比与实测结果所得到的三点弯曲试验表明,在图  1以及作为结果由有限元分析。三点弯曲 试验是用英斯特朗 4206年不足 1毫米 /分钟位移速率和有限元分析是演出与商业软件 ANSYS5.5(美国)使用壳牌 99和固体 95元素。表 1显示尺寸夹心标本。夹心束标本制成的复合材料的表面和内部核心。加入表面和核心,即是 4 一种粘合剂形状(  af126 ,  3 M公司,美国)和环氧粘合剂图 1。尺寸的简支夹层梁用三点弯曲试验:  (一)纵向方向 ; (二)  横截面 A-A1。  。  表 1  尺寸(  mm )的简支夹层梁下 threepoint 弯曲试验   ( 2216, 3M 公司,美国)  ,是用来防止脱层失败的夹层结构 17,18。单向碳纤维环氧复合(  usn150 ,韩国化学,韩国)  与玻璃纤维布复合(  gep215 ,韩国化学,  韩国)被用于表面材料,而芳纶纤维蜂窝(  hrh-10-1/8-4.0 ,  hexcel ,英国)  用于核心材料。表 2 和表 3 列出性能这些材料。综合面孔为夹心基础打下了一个堆叠序列  。凡标 G 和 C 代表了玻璃纤维和碳 -环氧分别。  图 2 显示实测挠度以及由于计算的,由梁理论和有限元分析而来。梁理论和有限元分析预言实验偏转 8 以内的误差。  从以上结果,我们发现在这该夹层梁挠度因剪是不容忽视(在这种情况下 3 倍以 上,由于弯曲)。  因此,箱式混合梁方面钢筋与钢板所示图。  3 采用混合标架,以减少剪切变形的夹层梁。对于梁的钢筋与钢板忽视翘曲,剪应力 和,它的几何兼容性详情如下:   其中 R 的比例应是剪切模量之间的钢 和蜂窝 项。然后,剪应力蜂窝图。  2.2设计的重量轻的复合钢筋机工具框   5 图 4显示照片的高速数控机床铣床的 15千瓦配备 35000rpm时,   图 4 照片上的高速铣床结构(  f500 ,大宇重工机械有限公司,韩国)。  主轴及混合标架,水平坐标(十 -坐标)及垂直坐标(  Y型坐标)  ,其垂直柱和横向柱钢筋与复合 材料夹层结构和复合材料板(  f500 ,大宇重工  机械有限公司,韩国)  。无论是移动所得到了 2.0米 /秒的速度,还是达到最大加速度 14.0 m/s ,都无结果。  5和 6显示照片的 X坐标和 Y型坐标组成的复合材料夹层结构胶接,以焊接钢管结构。为了估计该机床结构挠度,在高加速度,  移动钢框架结构进行了分析,得到了有限元分析显示图。  如垂直的 X坐标抵消了所吸收的 20千牛力量产生的,由两个直线电机装内表面的垂直方向的 X -坐标。  横栏的 Y型滑坡发生变形,在 Z向由弯矩由于要伸出主轴重量 4000 N,以最大限度地加固效 果,在这项工作中,立柱的 X -坐标和横向栏的 Y坐标被选作主要加强部分。  为了克服这个困难,混合帧的 X钢铁基地,制成 16毫米的钢板变成 20毫米厚的钢板。  常规之一,是增强复合材料夹层结构显示图。自剪变形的一个简单的三角形结构通常大,在这项研究中,混合结构的目的是作为盒型结构参考。  后来,其双方均加强了钢铁板块。  为设计的箱式混合结构大于 10.4 ,这意味着偏转由于剪切小于8.8 的总偏转。因此,在设计中的结构,抗弯刚度 D的使用为目标参数,如   由于加固外,以增加抗弯刚度 d 时,内面厚度的夹心决定考虑加入 5 毫 米的内在面临的夹层梁,以钢铁为主,以螺栓为主。  厚度上,夹层梁被初步确定给予最主要的一个,然后再较具体的计算,以确定合适的尺寸并利用有限元法考虑当地翘曲或扭 6 曲。从分析中,发现较大偏转发生在混合动力梁时,梁有相同的抗弯刚度 d ,因为交夹不具备横向加固钢板,而常规钢梁被设计成一个格子型结构与加强板,图  9 。因此,外面厚度的夹层梁增加至 13 毫米。  此外,尺寸的其他抗弯刚度 D 和计算,然后与有限元法考虑翘曲的结构。   2.3 制造混联机床结构高强度碳纤维环氧复合(  usn150 ,韩国化学,韩国)和玻璃纤维环氧(  gep215 ,韩国化学,韩国)  ,主要用于面孔夹层梁和加固板为 X和 Y 型。垂直栏的 X 抗滑被钢筋与两个夹层梁的 1462 毫米和 1223 毫米长,而在顶部和底部部分钢筋分别与四个复合板六小夹层梁所示图  5 。该 Y 型,即主轴单元的铣削应该抵制弯矩产生主轴的重量,切削力和惯性力由于快速加速和减速而下落了。  横栏的 Y 型与严格的三维制约因素是钢筋,具有很高的弹性模量碳纤维环氧复合材料的性能,给出表 2 (  hyej34m45d ,三菱,日本)  ,以避免干扰其他部分。此外,左右垂直柱的 Y 型被钢筋与三角梁所示图 6。此外,四个三角 形板被用于加强扭刚度的矩形框。综合增援保税区向钢铁基地结构与环氧粘合剂( 2216 , 3M 公司,美国)精却结合起来,同机械结合,与螺栓,以提高可靠性和生产效率。    7 Design and manufacture of composite high speed machinetool structures Dai Gil Lee *, Jung Do Suh, Hak Sung Kim, Jong Min Kim Abstract The high transfer speed as well as the high cutting speed of machine tools is important for the productivity improvement in thefabrication of molds/dies because non-machining time, called the air-cutting-time, amounts to 70% of total machining time withcomplex shape products. One of the primary reasons for low productivity is large mass of the moving parts of machine tools, whichcannot afford high acceleration and deceleration encountered during operation. Moreover, the vibrations of the machine toolstructure are among the other causes that restrict high speed operations.In this paper, the slides of high speed CNC milling machines were designed with fiber reinforced composite materials toovercome this limitation. The vertical and horizontal slides of a large CNC machine were manufactured by joining high-moduluscarbon-fiber epoxy composite sandwiches to welded steel structures using adhesives and bolts. These composite structures reducedthe weight of the vertical and horizontal slides by 34% and 26%, respectively, and increased damping by 1.5 5.7 times withoutsacrificing the stiffness. Without much tuning, this machine had a positional accuracy of  5 lm per 300 mm of the slidedisplacement. 1. Introduction CNC milling machines and machining centers areemployed in the fabrication of various molds/dies thatare used for electrical appliances, automobile interiors, stamping and injection molding. During normal machiningwith machine tools, their cutting tools aremoved with nominal feed rates, while the feed rates  8 are switched to a rapid traverse mode during the transfer ofcutting tools without contacting workpieces: The timespent to transfer a cutting tool without contactingworkpieces is called air-cutting-time. Generally, onlyabout 30% of the total machining time is spent in theactual cutting or making chips, while the remaining 70%is spent in the air-cutting-time 1,2. Therefore, not onlyhigh cutting speeds but also high transfer speeds arerequired to obtain the enhanced productivity of machiningwhich is essential to survive in the global competitionof machine tool markets. Although the cuttingspeed has been increased due to newly developed cuttingtool materials such as ceramic, CBN, diamond and soon, productivity is still restricted by the low transferspeed of massive moving frames which are usually madeof steel. Conventional steel moving frames of machinetools operate with maximum speeds of 0.2 0.8 m/s, andmaximum acceleration of 0.2 2.1 m/s2 (ConventionalMachining Center, Mynx400/ACE-TC320D, DaewooHeavy Industries & Machinery Ltd., Korea). However,modern high speed milling machines are required tohave the maximum acceleration of 14 m/s2 and the speedof 2 m/s. These high transfer speeds are hard to be realizedif massive steel moving frames are employed.Furthermore, machine tool structures vibrate creatingproblems during manufacturing at these high speeds,which may result in poor quality products by the relativepositional error between the cutting tools and workpieces3 5: Recently machine tools are required to havebeen kept the positional accuracy within  10 lm, whichis closely related to the precision of products 6. For thehigh speed operation with accuracy, machine toolstructures should be designed with light moving frameswithout sacrificing stiffness and damping properties,which are contradictory requirements if conventionalmetallic materials are employed because conventionalmetals have almost same low specific stiffness (E=q) withlow damping characteristics. Machine tool structureswith high specific stiffness and high damping are requiredto increase their fundamental natural frequenciesand decrease the  9 vibration induced. The requirement ofhigh specific stiffness with high damping for high speedmachine tool structures can be satisfied by employingfiber reinforced polymer composite materials 7,8. Sincethe fiber reinforced composite materials consist of reinforcingfibers with very high specific stiffness and matrixwith high damping, the resulting material characteristicsof composite materials reflect the best characteristics ofeach material, i.e., high specific stiffness with highdamping. Moreover, sandwich structures whose facestructures are made of fiberreinforced composite materialsand whose core materials are made of honeycombor foam structures maximize their advantages when theyare applied to the structures resisting bending moment.Consequently, sandwich structures and composite materialshave been employed increasingly in spacecrafts,airplanes, automobile parts 9, robot arms 8,10, andeven machine tools 11,12.The deformation of machine tool structures undercutting forces and structural inertia loads during startand stop motions produces not only poor qualityproducts but also noise and vibration. A simple way toreduce the deformation is to employ structures withlarge cross-sections. However, it increases the mass ofmachine tool structures and consequently requires largemotors, bearings and motion guide systems. Therefore,the best way to enhance the stiffness of machine toolstructures without much increase of mass is to employhigh specific stiffness structures such as compositesandwich structures.In this study, the vertical and horizontal machine toolslides of a high speed CNC milling machine were designedand manufactured with sandwich compositestructures that are adhesively bonded to welded steelstructures  a hybrid machine tool structure. The verticalcolumn of the horizontal slide (X-slide) was manufacturedwith composite sandwich structures while thehorizontal column of the vertical slide (Y-slide) wasreinforced with high modulus composite plates. Thehybrid structures were designed to have the equivalentstructural stiffness of conventional steel structures,which was calculated by the classical beam theory andFEM analysis. Then, the natural  10 frequency and dampingcapacity as well as weight savings of the compositehybrid machine tool structures were measured and compared with those of comparable conventional steelmachine tool structures. 2. Design of hybrid machine tool structures 2.1. Characteristics of hybrid beam The bending stiffness D of a simply supported sandwichbeam as shown in Fig. 1 is expressed as followswhen Ef >> Ec and d >> t 13 15:              ( 1) where Ef and Ec represent the Young s moduli of faceand core, respectively. The deflection D of the simplysupported sandwich beam under a concentrated load P based on the simple beam theory is the sum of D1 due tobending deformation and D2 due to shear deformation15,16: where A and Gc represent equivalent cross-section areaand the shear modulus of core material, respectively.Since the sandwich structure has low core shear stiffness,the simple beam theory neglecting shear deformationmay not give an accurate result. Therefore, the calculatedresults of stiffness of sandwich beam specimen werecompared with the measured results obtained by thethree-point bending test shown in Fig. 1 as well as theresults by FEM analysis. The three-point bending testwas performed using Instron 4206 under 1 mm/mindisplacement rate and the FEM analysis was performedwith a commercial software ANSYS 5.5 (USA) usingshell 99 and solid 95 elements. Table 1 shows the dimensionsof sandwich specimens. The sandwich beamspecimens were made of composite faces and honeycombcore. To join the faces and the core, both an  11 adhesivefilm (AF126, 3M, USA) and an epoxy adhesive  Fig. 1. Dimensions of the simply supported sandwich beam used forthree-point bending test: (a) longitudinal direction; (b) cross-section ofA A1. Table 1 Dimensions (mm) of the simply supported sandwich beam under threepointbending test (2216, 3M, USA) was used to prevent delaminationfailure of sandwich structures 17,18. Unidirectionalcarbon-epoxy composite (USN150, SK Chemical, Korea)and glass fabric composite (GEP215, SK Chemical,Korea) were used for the face material while aramid fiberhoneycomb (HRH-10-1/8-4.0, Hexcel, UK) wasused for the core material. Tables 2 and 3 list theproperties of these materials. The composite faces forthe sandwich specimens were laid up with a stackingsequence of 0 2;G/0 10;C/0 1;G/0 5;CS where the subscriptsG and C represent glass-fabric and carbon-epoxy, respectively.Fig. 2 shows the measured deflection as wellas the calculated ones by the beam theory and FEManalysis. Both the beam theory and the FEM analysispredicted the experimental deflection within 8% error.From the above results, it was found that the deflectionof the sandwich beam due to shear was not negligible(three times larger than that due to bending in this case).Therefore, box type hybrid beams with side surfacesreinforced with steel plates as shown in Fig. 3 wereadopted for the hybrid moving frames to reduce theshear  12 deformation of the sandwich beam. For the boxtype beams reinforced wit

温馨提示

  • 1. 本站所有资源如无特殊说明,都需要本地电脑安装OFFICE2007和PDF阅读器。图纸软件为CAD,CAXA,PROE,UG,SolidWorks等.压缩文件请下载最新的WinRAR软件解压。
  • 2. 本站的文档不包含任何第三方提供的附件图纸等,如果需要附件,请联系上传者。文件的所有权益归上传用户所有。
  • 3. 本站RAR压缩包中若带图纸,网页内容里面会有图纸预览,若没有图纸预览就没有图纸。
  • 4. 未经权益所有人同意不得将文件中的内容挪作商业或盈利用途。
  • 5. 人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对用户上传分享的文档内容本身不做任何修改或编辑,并不能对任何下载内容负责。
  • 6. 下载文件中如有侵权或不适当内容,请与我们联系,我们立即纠正。
  • 7. 本站不保证下载资源的准确性、安全性和完整性, 同时也不承担用户因使用这些下载资源对自己和他人造成任何形式的伤害或损失。

评论

0/150

提交评论