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1、 南京大學畢業(yè)設計(論文)外文資料翻譯系部: 機械工程系 專 業(yè): 機械工程及自動化 姓 名: 學 號: 外文出處: 附 件: 1.外文資料翻譯譯文;2.外文原文。 指導教師評語:譯文基本能表達原文思想,語句較流暢,條理較清晰,專業(yè)用語翻譯基本準確,基本符合中文習慣,整體翻譯質量一般。 簽名: 年 月 日附件1:外文資料翻譯譯文 下沉指數(shù)最小翹曲、注塑件熱塑性田口優(yōu)化方法 大加那利島拉斯帕爾馬斯大學,機械工程學院,西班牙摘要:在過去幾年里快速成型和快速模具技術已被廣泛開發(fā)利用。在本文中,使用電芯作為核心程序分析塑料注塑模具。通過差分系統(tǒng)快速成型制造外殼模型。主要目的是分析電鑄鎳殼力學特點,研究
2、相關的金相組織,硬度,內部壓力等不同方面,由這些特征參數(shù)來生產電鑄設備的外殼。最后一個核心是檢驗注塑模具。關鍵詞:電鍍,電鑄,微觀結構,鎳文章大綱:1 、導言2 、制造過程的注塑模具3 、獲得電殼:設備4 、獲得硬度5 、金相結構6 、內部壓力7 、檢驗注塑模具8 、結論正文:1 、導言現(xiàn)代工業(yè)面臨巨大的挑戰(zhàn),其中的最重要的挑戰(zhàn)是怎樣解決提供給消費者更好的產品,更多的種類和更新?lián)Q代(更新設計)的問題 。出于這個原因,現(xiàn)代工業(yè)必定產生越來越激烈的競爭性。毫無疑問,結合時間變量和質量變量是不容易的,因為他們經常彼此互為條件,先進的生產系統(tǒng)將允許該組合以更加有效可行的方式進行,例如,如果是觀察注塑系
3、統(tǒng)的演變,我們得出的結論是,事實上一個新產品在市場上具有較好的質量它需要越來越少的時間??焖倌>咧圃旒夹g是在這一領域中可以改善設計和制造注入部分的技術進步??焖倌>咧圃旒夹g基本上是一個中小型系列的收集程序,在很短的時間內在可接受的精度水平基礎上讓我們獲得模具的塑料部件。其應用不僅僅在決策領域的塑料注射件1 -3,然而這是真的。本文包含了很廣泛的研究路線,并試圖在那里學習,定義,分析,測試,提出在工業(yè)水平方面的可行性,從核心的注塑模具制造獲取電鑄鎳殼,同時作為一個初始模型的原型在一個fdm設備上的快速成型。不得不說的是,先進的電鑄技術應用在無數(shù)的行業(yè),這一研究工作調查到什么程度,并根據(jù)這些參數(shù),
4、使用這種技術生產快速模具在技術上是可行的。所有取得準確的和系統(tǒng)化的使用方式,并提出了工作方法。2 、制造過程的注塑模具薄鎳外殼的核心是電鑄,獲得一個充滿epoxic金屬樹脂的一體化的核心板塊4模具(圖1 )允許直接制造注射型多用標本,因為它們確定了新英格蘭大學英文國際標準化組織3167標準。這樣做的目的是確定力學性能的材料收集代表行業(yè)。圖 1 注塑模具制造與電的核心該階段取得的核心4 ,根據(jù)該方法研究了這項工作,如下: (a)cad系統(tǒng)的理想對象。(b)示范制造業(yè)的快速成型設備(頻分多路系統(tǒng)) 。所使用的材料將是一個abs塑料。(c)電鑄鎳殼的模式,已事先涂有導電涂料(它必須有導電性) 。(d
5、)無外殼的模式。(e)制作的核心是背面外殼的環(huán)氧樹脂抗高溫與銅管的制冷。注塑有兩個腔的具,其中一個是電核心和其他直接加工的移動板。因此,在同一工藝條件下,同時注入兩個標準腔技術制造,獲得相同的工件。3 、獲得電殼:設備電5 6是電解質時電流的化學變化。電解所形成的直流電有兩個電極,陽極和陰極。當電流流經電路,在離子溶液中轉化為原子。電鍍液用于這項工作是由氨基磺酸鎳 7 8 400毫升/升,氯化鎳( 10克/升) ,硼酸( 50克/升) , allbrit sla( 30毫升/ l )和allbrite 703 ( 2毫升/升) 。選擇這一成分,主要是由于我們考慮注塑模具程序是玻璃纖維。氨基磺酸
6、鎳使我們能夠獲得一個可以接受水平的內部壓力(測試了不同的工藝條件結果,而不是最佳工藝條件為約2兆帕最高為50兆帕)。然而,這種內部壓力,是由toluenesulfonamide衍生物和甲醛水溶液使用的allbrite添加劑的結果,添加劑也增加了殼的阻力。 allbrite 703是一種可生物降解的水溶液作用劑。氯化鎳,有利于統(tǒng)一解決金屬分布在陰極,提高導電性的問題。硼酸作為ph值的緩沖區(qū)。該設備用于制造殼的測試如下: 聚丙烯: 600毫米× 400毫米× 500毫米大小。三個800瓦聚四氟乙烯電阻器機械攪拌系統(tǒng)的陰極。 系統(tǒng)的循環(huán)和過濾用的泵和聚丙烯過濾器。充電整流器。最大
7、強度在連續(xù)50個a和連續(xù)電流電壓介于0和16v籃鈦鎳陽極(鎳硫回合電解鎳) ,純度99 以上。氣體注系統(tǒng)一旦電流密度( 1至22 a/dm2 ) ,溫度( 35至55 ° c )和ph值已經確定,執(zhí)行參數(shù),測試的進程部分就不可改變。4 、獲得硬度電殼硬度的測試一直保持的相當高和穩(wěn)定結果。如圖 2??梢钥吹剑弘娏髅芏戎?.5到a/dm2 ,硬度值介于540到580高壓,ph值為4 ± 0.2和溫度為45攝氏度,如果ph值減少到3.5和溫度為55 ,硬度為520以上,高壓低于560 。這一測試使常規(guī)組成不同于其他氨基磺酸鎳,允許其運營更加廣泛;然而,這種operativity將
8、是一定的取決于其他因素,如內部壓力,因為它的變異可能改變ph值,電流密度和溫度等。另一方面,傳統(tǒng)的硬度氨基磺酸高壓200-250之間,遠低于取得的一個試驗結果。這是必須考慮到的,對于一個注塑模具,硬度可以接受的起點300高壓。注塑模具中最常見的材料,有改善鋼( 290高壓) ,整體鋼淬火( 520-595高壓) , casehardened鋼鐵( 760-800高壓)等,以這樣一種方式,可以看到,注塑模具硬度水平的鎳是殼內的高范圍的材料。因為這是一個負責內部壓力的塑料注射液,這種方式與環(huán)氧樹脂灌漿將遵循它,相反對低韌性的殼補償,這就是為什么它是必定盡可能的外殼厚度均勻,并沒有重要的原因,如 腐
9、蝕圖 2 硬度隨電流密度 ph值為4 ± 0.2 ,溫度為45攝氏度5 、金相結構為了分析金相結構的電流密度和溫度主要變化。在正面橫向部分(垂直沉積)對樣品進行了分析。為了方便地封裝在樹脂、拋光、銘刻,在不同階段的混合乙酸和硝酸。該蝕刻間隔為15 、 25 、 40和50之后再次拋光,為了在金相顯微鏡下觀察奧林巴斯pme3-adl 3.3×/10×。必須要說的是,這一條規(guī)定顯示了圖片之后的評論,用于制造該模型的殼在fdm快速成型機里溶化的塑料材料(澳大利亞統(tǒng)計局)鞏固和解決了該階層。后來在每一個層,擠出的模具都留下一個大約0.15毫米直徑橫向和縱向的線程。因此,在
10、表面可以看到細線表明頭部的機器。這些線路將作為參考信息解決鎳的重復性問題。重復性的模型將作為一個基本要素來評估注塑模具表面紋理。表1 測試系列系列ph溫度(°c) 電流密度 (a/dm2) 14.2 ± 0.2552.2223.9 ± 0.2455.5634.0 ± 0.24510.0044.0 ± 0.24522.22圖3說明該系列第一蝕刻表面的樣本.它顯示了流道起點的頻率復用機,這就是說,有一個很好的重復性。它不能仍然注意到四舍五入結構。在圖 4 .系列2 ,經
11、過第二次,可以看到一條線的流道的方式與以前的相比不太清楚。在圖 5 .系列3,雖然第二次蝕刻開始出現(xiàn)圓形晶結構是非常困難的。此外,最黑暗的部分表明蝕刻不足的進程和組成。圖 3 系列1 ( × 150 ) ,蝕刻1圖 4 系列2 ( × 300 ) ,蝕刻2 圖 5 系列3 ( × 300 ) ,蝕刻2 這種現(xiàn)象表明,在低電流密度和高溫條件下工作,得到更小的晶粒尺寸和殼重現(xiàn)性好,就是所需的足夠的應用程序。如果分析橫向平面進行的沉積,可以在所有測試樣品和條件增長的結構層(圖6 ) ,犧牲一個低延展性取得令人滿意的高機械阻力。最重要的是添加劑的使用情況,氨基磺酸鎳鍍液的
12、添加劑通常創(chuàng)建一個纖維和非層狀結構9。這個問題表明,在任何情況下改變潤濕劑,由于該層結構的決定因素是這種結構的應力減速器( allbrite sla) 。另一方面,它也是測試的層狀結構不同厚度層中的電流密度。圖 6 橫向平面系列2 ( × 600 ) ,蝕刻2 6 、內部壓力殼的一個主要特點是應該有其應用,如插入是要有一個低水平的內部壓力。測試不同的溫度和電流密度,所采取的措施取決于陰極彎曲張力計法。 a鋼測試控制使用側固定和其他自由度固定(160毫米長, 12.7毫米寬和0.3毫米厚度)。金屬沉積只有在控制了機械拉伸力(拉伸或壓應力),才能計算內部壓力。彈性的角度來看,斯托尼模型1
13、0應用,假定鎳基質厚度,對部分鋼材產生足夠?。?3微米)的影響。在所有的測試情況下,一個能夠接受的應用程序在內部壓力在50兆帕的極端條件下和2兆帕的最佳條件下產生。得出的結論是,內部壓力在不同的工作條件和參數(shù)沒有明顯變化的條件下沒有太大變化。7 、檢驗注塑模具試驗已進行了各種代表性的熱塑性材料,如聚丙烯,高密度聚乙烯和pc材料,并進行了注射部件性能的分析,如尺寸,重量,阻力,剛度和柔性。對殼的力學性能進行了拉伸破壞性測試和分析。大約500個注射液在其余的條件下,進行了更多的檢驗??傮w而言,為分析一種材料,重要的是注意到行為標本中的核心和那些加工腔之間的差異。然而在分析光彈注入標本(圖7)有人注
14、意到不同的國家之間的張力存在兩種不同類型的標本,是由于不同的模腔熱傳遞和剛度。這種差異解釋了柔性的變化更加突出的部分晶體材料,如聚乙烯和聚酰胺6 。圖 7 分析光彈注入標本有人注意到一個較低的柔性標本在的高密度聚乙烯分析測試管在鎳核心的情況下,量化30 左右。如尼龍6這個值也接近50 。8 、結論經過連續(xù)試驗,注塑模具在不同的條件下檢查的氨基磺酸鎳鍍液使用添加劑,這就是說塑性好,硬度好和摩擦力好的層狀結構,已取得的力學性能是可以接受的。機械缺陷的鎳殼將部分取代環(huán)氧樹脂為核心的注塑模具,使注入的一系列中型塑料零部件達到可接受的質量水平。參考文獻1 a.e.w. rennie, c.e. bock
15、ing and g.r. bennet.電鑄電極快速成型軸的電火花加工.學者材料,(2001年). 186-196頁.2 p.k.d.v. yarlagadda, i.p. ilyas and p. chrstodoulou.模具的快速發(fā)展使用鎳電鑄和立體光刻工藝.學者材料,(2001年).286-294頁.3 j. hart, a. watson, electroforming:一種基本上未擴大,但關鍵行業(yè), interfinish 96 , 14世界大會上,英國伯明翰, 1996年. 4 m. monzón .阿根廷布宜諾斯艾利斯國際塑料雜志modernos , 84 (2002
16、).第557頁.5 l.f. hamilton. 希爾的化學及分析.(1989年). 6 e. julve. electrodeposición德金屬. 2000年( ejs ). 7 a. watson.鎳氨基磺酸鹽解決方案.鎳發(fā)展研究所(1989年).8 a. watson.補充氨基磺酸鹽鎳解決方案.鎳發(fā)展研究所(1989年).9 j. dini.電鍍材料科學的涂膜及襯底.諾伊斯出版(1993年).10 j.w. judy.磁性微與多晶硅屈.信息科學技術部,加州大學伯克利分校, 1994年. 附件2:外文原文(復印件)a technical note on the charact
17、erization of electroformed nickel shells for their application to injection molds auniversidad of las palmas of gran canaria, departamento of ingenieria mecanica, spain abstractthe techniques of rapid prototyping and rapid tooling have been widely developed during the last years. in this article, el
18、ectroforming as a procedure to make cores for plastics injection molds is analysed. shells are obtained from models manufactured through rapid prototyping using the fdm system. the main objective is to analyze the mechanical features of electroformed nickel shells, studying different aspects related
19、 to their metallographic structure, hardness, internal stresses and possible failures, by relating these features to the parameters of production of the shells with an electroforming equipment. finally a core was tested in an injection mold. keywords: electroplating; electroforming; microstructure;
20、nickel article outline1. introduction 2. manufacturing process of an injection mold 3. obtaining an electroformed shell: the equipment 4. obtained hardness 5. metallographic structure 6. internal stresses 7. test of the injection mold 8. conclusions references1. introductionone of the most important
21、 challenges with which modern industry comes across is to offer the consumer better products with outstanding variety and time variability (new designs). for this reason, modern industry must be more and more competitive and it has to produce with acceptable costs. there is no doubt that combining t
22、he time variable and the quality variable is not easy because they frequently condition one another; the technological advances in the productive systems are going to permit that combination to be more efficient and feasible in a way that, for example, if it is observed the evolution of the systems
23、and techniques of plastics injection, we arrive at the conclusion that, in fact, it takes less and less time to put a new product on the market and with higher levels of quality. the manufacturing technology of rapid tooling is, in this field, one of those technological advances that makes possible
24、the improvements in the processes of designing and manufacturing injected parts. rapid tooling techniques are basically composed of a collection of procedures that are going to allow us to obtain a mold of plastic parts, in small or medium series, in a short period of time and with acceptable accura
25、cy levels. their application is not only included in the field of making plastic injected pieces 1, 2 and 3, however, it is true that it is where they have developed more and where they find the highest output. this paper is included within a wider research line where it attempts to study, define, a
26、nalyze, test and propose, at an industrial level, the possibility of creating cores for injection molds starting from obtaining electroformed nickel shells, taking as an initial model a prototype made in a fdm rapid prototyping equipment. it also would have to say beforehand that the electroforming
27、technique is not something new because its applications in the industry are countless 3, but this research work has tried to investigate to what extent and under which parameters the use of this technique in the production of rapid molds is technically feasible. all made in an accurate and systemati
28、zed way of use and proposing a working method. 2. manufacturing process of an injection moldthe core is formed by a thin nickel shell that is obtained through the electroforming process, and that is filled with an epoxic resin with metallic charge during the integration in the core plate 4 this mold
29、 (fig. 1) permits the direct manufacturing by injection of a type a multiple use specimen, as they are defined by the une-en iso 3167 standard. the purpose of this specimen is to determine the mechanical properties of a collection of materials representative industry, injected in these tools and its
30、 comparison with the properties obtained by conventional tools. fig. 1. manufactured injection mold with electroformed core.the stages to obtain a core 4, according to the methodology researched in this work, are the following: (a) design in cad system of the desired object.(b) model manufactur
31、ing in a rapid prototyping equipment (fdm system). the material used will be an abs plastic.(c) manufacturing of a nickel electroformed shell starting from the previous model that has been coated with a conductive paint beforehand (it must have electrical conductivity).(d) removal of the shell from
32、the model.(e) production of the core by filling the back of the shell with epoxy resin resistant to high temperatures and with the refrigerating ducts made with copper tubes.the injection mold had two cavities, one of them was the electroformed core and the other was directly machined in the moving
33、platen. thus, it was obtained, with the same tool and in the same process conditions, to inject simultaneously two specimens in cavities manufactured with different technologies. 3. obtaining an electroformed shell: the equipmentelectrodeposition 5 and 6 is an electrochemical process in which a chem
34、ical change has its origin within an electrolyte when passing an electric current through it. the electrolytic bath is formed by metal salts with two submerged electrodes, an anode (nickel) and a cathode (model), through which it is made to pass an intensity coming from a dc current. when the curren
35、t flows through the circuit, the metal ions present in the solution are transformed into atoms that are settled on the cathode creating a more or less uniform deposit layer. the plating bath used in this work is formed by nickel sulfamate 7 and 8 at a concentration of 400 ml/l, nickel chloride
36、(10 g/l), boric acid (50 g/l), allbrite sla (30 cc/l) and allbrite 703 (2 cc/l). the selection of this composition is mainly due to the type of application we intend, that is to say, injection molds, even when the injection is made with fibreglass. nickel sulfamate allows us to o
37、btain an acceptable level of internal stresses in the shell (the tests gave results, for different process conditions, not superior to 50 mpa and for optimum conditions around 2 mpa). nevertheless, such level of internal pressure is also a consequence of using as an additive allbrite sla,
38、which is a stress reducer constituted by derivatives of toluenesulfonamide and by formaldehyde in aqueous solution. such additive also favours the increase of the resistance of the shell when permitting a smaller grain. allbrite 703 is an aqueous solution of biodegradable surface-acting agents that
39、has been utilized to reduce the risk of pitting. nickel chloride, in spite of being harmful for the internal stresses, is added to enhance the conductivity of the solution and to favour the uniformity in the metallic distribution in the cathode. the boric acid acts as a ph buffer. the equipment used
40、 to manufacture the nickel shells tested has been as follows: polypropylene tank: 600 mm × 400 mm × 500 mm in size. three teflon resistors, each one with 800 w. mechanical stirring system of the cathode. system for recirculation and filtration of the
41、 bath formed by a pump and a polypropylene filter. charging rectifier. maximum intensity in continuous 50 a and continuous current voltage between 0 and 16 v. titanium basket with nickel anodes (inco s-rounds electrolytic nickel) with a purity of 99%. gases aspiration system.once the bath
42、has been defined, the operative parameters that have been altered for testing different conditions of the process have been the current density (between 1 and 22 a/dm2), the temperature (between 35 and 55 °c) and the ph, partially modifying the bath composition. 4. obtained hardnesson
43、e of the most interesting conclusions obtained during the tests has been that the level of hardness of the different electroformed shells has remained at rather high and stable values. in fig. 2, it can be observed the way in which for current density values between 2.5 and 22 a/dm2, the hardne
44、ss values range from 540 and 580 hv, at ph 4 ± 0.2 and with a temperature of 45 °c. if the ph of the bath is reduced at 3.5 and the temperature is 55 °c those values are above 520 hv and below 560 hv. this feature makes the tested bath different from
45、 other conventional ones composed by nickel sulfamate, allowing to operate with a wider range of values; nevertheless, such operativity will be limited depending on other factors, such as internal stress because its variability may condition the work at certain values of ph, current density or tempe
46、rature. on the other hand, the hardness of a conventional sulfamate bath is between 200250 hv, much lower than the one obtained in the tests. it is necessary to take into account that, for an injection mold, the hardness is acceptable starting from 300 hv. among the most usual materials fo
47、r injection molds it is possible to find steel for improvement (290 hv), steel for integral hardening (520595 hv), casehardened steel (760800 hv), etc., in such a way that it can be observed that the hardness levels of the nickel shells would be within the mediumhigh range of the mate
48、rials for injection molds. the objection to the low ductility of the shell is compensated in such a way with the epoxy resin filling that would follow it because this is the one responsible for holding inwardly the pressure charges of the processes of plastics injection; this is the reason why it is
49、 necessary for the shell to have a thickness as homogeneous as possible (above a minimum value) and with absence of important failures such as pitting. fig. 2. hardness variation with current density. ph 4 ± 0.2, t = 45 °c.5. metallographic structurein order t
50、o analyze the metallographic structure, the values of current density and temperature were mainly modified. the samples were analyzed in frontal section and in transversal section (perpendicular to the deposition). for achieving a convenient preparation, they were conveniently encapsulated in resin,
51、 polished and etched in different stages with a mixture of acetic acid and nitric acid. the etches are carried out at intervals of 15, 25, 40 and 50 s, after being polished again, in order to be observed afterwards in a metallographic microscope olympus pme3-adl 3.3×/10×. before going
52、 on to comment the photographs shown in this article, it is necessary to say that the models used to manufacture the shells were made in a fdm rapid prototyping machine where the molten plastic material (abs), that later solidifies, is settled layer by layer. in each layer, the extruder die leaves a
53、 thread approximately 0.15 mm in diameter which is compacted horizontal and vertically with the thread settled inmediately after. thus, in the surface it can be observed thin lines that indicate the roads followed by the head of the machine. these lines are going to act as a reference to indica
54、te the reproducibility level of the nickel settled. the reproducibility of the model is going to be a fundamental element to evaluate a basic aspect of injection molds: the surface texture. the tested series are indicated in table 1. table 1. tested series series ph temperature (°c) current den
55、sity (a/dm2) 14.2 ± 0.2552.2223.9 ± 0.2455.5634.0 ± 0.24510.0044.0 ± 0.24522.22fig. 3 illustrates the surface of a sample of the series after the first etch. it shows the roads originated by the fdm machine, that is to say that there is a g
56、ood reproducibility. it cannot be still noticed the rounded grain structure. in fig. 4, series 2, after a second etch, it can be observed a line of the road in a way less clear than in the previous case. in fig. 5, series 3 and 2° etch it begins to appear the rounded grain structure although it
57、 is very difficult to check the roads at this time. besides, the most darkened areas indicate the presence of pitting by inadequate conditions of process and bath composition. fig. 3. series 1 (×150), etch 1.fig. 4. series 2 (×300), etch 2.fig. 5. series 3 (×300), etch
58、2.this behavior indicates that, working at a low current density and a high temperature, shells with a good reproducibility of the model and with a small grain size are obtained, that is, adequate for the required application. if the analysis is carried out in a plane transversal to the deposition, it can be tested in all the samples and for all the conditions that the growth structure of the deposit is laminar (fig. 6), what is very satisfactory to obtain a high mechanical resistance although at the expense of a low ductibility. this quality is due
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