洗衣機排水管道某零件的注射模具設(shè)計【22張CAD圖紙+說明書完整資料】

購買設(shè)計請充值后下載，資源目錄下的文件所見即所得，都可以點開預(yù)覽，資料完整，充值下載就能得到?！咀ⅰ浚篸wg后綴為CAD圖，doc,docx為WORD文檔，【有不明白之處，可咨詢QQ:1304139763】 畢業(yè)設(shè)計 論文 開題報告 題目 洗衣機排水管道某零件的注射模具 設(shè)計 系 別 機電信息系 專 業(yè) 機械設(shè)計制造及其自動化 班 級 姓 名 學(xué) 號 導(dǎo) 師 2012 年 12 月 25 日 1 畢業(yè)設(shè)計 論文 綜述 題目背景 研究意義及國內(nèi)外相關(guān)研究情況 1 1 題目背景和目的 塑料模具的設(shè)計和制造水平反映了機械設(shè)計和加工的水平 模具的設(shè)計已應(yīng) 用了當(dāng)代先進的設(shè)計手段 各行各業(yè)對模具需求量的增大 增加了大量的模具設(shè) 計與制造的技術(shù)人才 本課題為中等以上難度的塑料模具設(shè)計 從模具的結(jié)構(gòu)設(shè) 計 各種參數(shù)的設(shè)計與計算 材料的選擇與處理 零件的加工工藝方案的制訂 三維造型等均得到一定的鍛煉 1 2 塑料模具的現(xiàn)狀和前景 伴隨著改革開放所帶來的各式各樣的新技術(shù)和新思想 我國的制造業(yè)得到了 的很大程度上的發(fā)展 并且擁有很廣闊的發(fā)展前景 模具是制造業(yè)不可或缺的一 部分 它是目前大部分行業(yè)必需的 很多行業(yè)都離不開模具 它涉及到機械設(shè)計 制造 塑性加工 鍛造 金屬材料及其熱處理 高分子材料 金屬物理 粉末冶 金 塑料 橡膠 玻璃等諸多學(xué)科 范疇和行業(yè) 利用成型的模具制造出的產(chǎn)品 所擁有的高生產(chǎn)率 高精度 高復(fù)雜性 高一致性和低消耗 這是其他的加工制 造方法無法比擬的 目前我國的模具生產(chǎn)廠家有 3 萬多家 從事該行業(yè)的人數(shù)已 達到 100 多萬人 我國的模具行業(yè)的發(fā)展具有以下這些特點 大型 精密 復(fù)雜 長壽命中高檔模具以及模具標準件的發(fā)展速度快于行業(yè)的總體發(fā)展水平 塑料模 和壓鑄模成比例增長 專業(yè)模具廠家數(shù)量及生產(chǎn)能力增加較快 隨著經(jīng)濟體制改 革的不斷深入 三資 及民營企業(yè)的發(fā)展很快 我國的模具生產(chǎn)主要集中在長江 三角洲和珠江三角洲等地區(qū) 雖然在模具總量上我國位列前茅 但是設(shè)計和制造 水平還是落后于歐美等發(fā)達國家 標準化程度也低于國際水平 從下表可以看出 來我國模具行業(yè)的現(xiàn)有水平和國際水平的差距 國內(nèi)水平 國外水平 注塑模型腔精度 0 02 0 05mm 0 005 0 1mm 型腔表面粗糙度 Ra 0 20 m Ra 0 01 0 05 m 非淬火鋼模具壽命 10 30 萬次 10 60 萬次 淬火鋼模具壽命 50 100 萬次 160 300 萬次 標準化程度 小于 30 70 80 中型塑料生產(chǎn)周期 2 4 個月 1 個月左右 在模具行業(yè)中的占有率 25 30 30 40 同時我國的模具行業(yè)還存在著整體利潤較低 進口多出口少的不利現(xiàn)狀 這說明 我國的模具技術(shù)與國外技術(shù)還存在著不小的差距 仍然需要大力發(fā)展 與此同時 我國的模具發(fā)展也有著一些有利因素 國家對制造業(yè)的重視和大力支持 我國高 速發(fā)展的機械制造業(yè) 汽車制造業(yè) 家電及建筑業(yè)等給模具行業(yè)帶來巨大的前景 和市場 國際先進企業(yè)來華投資熱情增高帶來的機遇等 1 3 塑料模具的發(fā)展趨勢 經(jīng)過近些年的發(fā)展 塑料模具取得了很大的進步和成果 同時也表現(xiàn)出了今 后的發(fā)展趨勢的方向 1 模具的精度越來越高 在 10 年前 精密模具的精度 一般為 5 m 而現(xiàn)在已經(jīng)達到 2 3 m 1 m 精度的模具也將要出現(xiàn) 2 模具越 來越趨近大型化 3 模具的技術(shù)含量越來越高 4 塑料模具的比例將會進一 步增高 5 新型多功能復(fù)合模具會得到進一步的發(fā)展 并且得到更加廣泛的應(yīng) 用 6 標準件的應(yīng)用會更加的廣泛 因為模具標準化以及模具標準件的應(yīng)用將 可以減小模具制造周期 同時還能提高模具的整體質(zhì)量和降低模具制造成本 7 隨著車輛和電機等產(chǎn)品向輕量化發(fā)展 壓鑄模的比例將不斷提高 同時對壓 鑄模的壽命和復(fù)雜程度也將提出越來越高的要求 8 熱流道模具在塑料模具中 的比重也將逐漸提高 9 隨著塑料成型工藝的不斷改進與發(fā)展 氣輔模具及適 應(yīng)高壓注塑成型等工藝的模具也將隨之發(fā)展 2 本課題研究的主要內(nèi)容和擬采用的研究方案 研究方法或措施 2 1 研究的主要內(nèi)容 該課題是通過設(shè)計注塑模具來熟悉和掌握塑料零件注射模具的設(shè)計全過程 首先先要熟悉該零件的結(jié)構(gòu) 之后能夠根據(jù)零件的結(jié)構(gòu)設(shè)計出注塑模具 然后還 要對該注塑模具的主要零件的進行強度計算 確定每一個零件的尺寸 并且要選 擇合適的材料 同時還要選擇合理的熱處理要求以及其制造工藝方法 2 2 研究方案 1 根據(jù)零件的外形和特點進行分析 從該零件的塑料品種 塑件形狀 尺寸精度 表面粗糙度等各方面考慮注塑 成型工藝的可行性和經(jīng)濟性 由于該零件是洗衣機內(nèi)部零件 初步選擇該制品材料為 ABS 丙烯腈 丁二烯 苯乙烯共聚物 該材料有良好的耐化學(xué)腐蝕 表面硬度 加工性和染色性 制 品的壁厚 熔料溫度對收縮率影響極小 同時 ABS 有較強的抗沖擊強度 且在低 溫下也不迅速下降 且該材料有一定的硬度和尺寸穩(wěn)定性 易于成型加工 2 分型面的選擇 分型面的選擇不僅關(guān)系到塑件的正常成型和脫模具 而且涉及模具結(jié)構(gòu)與制 造成本 選擇分型面的原則 分型面應(yīng)選擇在制品的最大截面處 無論塑件以何 方位布置型腔 都應(yīng)將此作為首要原則 有利于保證制品的外觀質(zhì)量 分型面上 型腔壁面稍有間隙 熔體就會在塑件上產(chǎn)生飛邊 盡可能使制品留在動模一側(cè) 因為在動模一側(cè)設(shè)置和制造脫模機構(gòu)簡便易行 有利于保證制品的尺寸精度 盡 可能滿足制品的使用要求 盡可能減少制品在合模方向上的投影面積 以減小所 需鎖模力 長型芯應(yīng)置于開模方向 當(dāng)塑件在相互垂直方向都需設(shè)置型心時 將 較短的型心設(shè)置在側(cè)抽芯方向 有利于減小抽拔距離 有利于排氣 在選擇非平 面分型面時 應(yīng)有利于型腔加工和制品的脫模方便 3 確定模具型腔數(shù)以及型腔的排列和流道布局以及澆口位置設(shè)置 4 根據(jù)零件的用途和作用計算零件的強度 由于該零件是洗衣機上的零件 因 此需要足夠的的強度來保證其正常運轉(zhuǎn) 5 設(shè)計澆筑系統(tǒng) 6 設(shè)計導(dǎo)出機構(gòu) 7 設(shè)計抽芯機構(gòu) 8 設(shè)計和計算溫度調(diào)節(jié)系統(tǒng) 9 選擇合適的模架 10 模具的裝配 3 本課題研究的重點及難點 前期已開展工作 3 1 本課題研究的重點及難點 1 確定設(shè)計方案 確定模具的分型面以及模具型腔數(shù) 2 計算零件的工作尺寸和公差 成型腔壁厚 型芯墊板厚度 3 確定加熱與冷卻系統(tǒng) 4 確定零件的材料以及熱處理工藝 3 2 前期已開展工作 1 熟悉本設(shè)計的要求 查閱文獻 收集相關(guān)資料 撰寫開題報告 2 分析零件的結(jié)構(gòu) 3 作出了零件的三維圖和二維圖 4 完成本課題的工作方案及進度計劃 按周次填寫 1 第1周 前期準備 查閱資料 了解課題 2 2 4 周 完成開題報告 進行開題檢查 3 5 8 周 完成中期報告 進行中期檢查 4 9 11 周 完成結(jié)構(gòu)設(shè)計和裝配圖的繪制 5 12 13 完成三位建模 并進行模型裝配 6 14 15 周 完善裝配模型 撰寫畢業(yè)論文 7 16周 整理資料 進行畢業(yè)答辯 參考文獻 1 塑料注射成型工藝及模具設(shè)計 第二版 李德群 黃志高主編 北京 機械工業(yè)出版社 2009 5 2 塑料成型工藝與模具設(shè)計 孫玲主編 清華大學(xué)出版社 2008 3 注塑成型工藝與模具設(shè)計 池成忠主編 北京 化學(xué)工業(yè)出版社 2010 8 4 我國塑料模具工業(yè)的現(xiàn)狀及發(fā)展趨勢 劉少達 仲愷農(nóng)業(yè)技術(shù)學(xué)院學(xué)報 17 3 66 71 2004 5 我國塑料模具現(xiàn)狀與發(fā)展趨勢 周永泰 期刊塑料 2000年第6期 29卷 6 塑料模具新型材料的種類與發(fā)展動向 楊俊秋 期刊模具技術(shù) 2007第3期 7 我國模具發(fā)展趨勢 期刊模具制造 2003 8 模具制造工藝學(xué) 黃毅宏 李明輝主編 北京 機械工業(yè)出版社 1999 6 9 塑料模具設(shè)計與結(jié)構(gòu)設(shè)計 顏智偉主編 北京 國防工業(yè)出版社 2006 10 塑料模具設(shè)計指導(dǎo) 第二版 伍先明主編 北京 國防工業(yè)出版社 2010 4 11 塑料成型工藝及模具設(shè)計 葉久新 王群主編 北京機械工業(yè)出版社 2007 11 12 注塑成型工藝 劉來英主編 北京 機械工業(yè)出版社 2004 10 13 實用注塑模具結(jié)構(gòu)圖集 洪慎章主編 北京 化學(xué)工業(yè)出版社 2009 8 14 注塑成型工藝分析及模具 高軍 李熹平 高田玉 褚興榮主編 北京 化學(xué)工業(yè)出 版社 2009 1 15 Pro E注塑模具設(shè)計與制造 肖愛民 戴峰澤 袁鐵軍主編 北京 化學(xué)工業(yè)出版社 2008 1 16 LIMT CORNEYJ RITCHIE J M et al Optimizing tool selection J International Journal of Producion Re2search 2001 39 17 Mita T Yamaguchi T Kashiwase T and Kawase T Realization og speed biped using modern control theory Int J Control 1984 40 107 119 18 Medrano Xenda G A and Eldukhri E E Biped robot locomotiong in the sagittal plane Trans Trans Inst Mcasmt and Control 1997 19 38 49 5 指導(dǎo)教師意見 對課題的深度 廣度及工作量的意見 指導(dǎo)教師 年 月 日 6 所在系審查意見 系主管領(lǐng)導(dǎo) 年 月 日 畢業(yè)設(shè)計 論文 中期報告 題目 洗衣機排水管道某零件的注射模具 設(shè)計 系 別 機電信息系 專 業(yè) 機械設(shè)計制造及其自動化 班 級 姓 名 學(xué) 號 導(dǎo) 師 2013 年 3 月 19 日 1 設(shè)計 論文 進展狀況 在本階段 主要完成的是畢業(yè)設(shè)計中的外文翻譯 模具裝配草圖 完善了塑件 的二維零件圖以及對該塑件更深層次的分析和理解 1 1 二維零件圖 通過對零件的更深入的理解 在初期的零件二維圖的基礎(chǔ)上更加完善了零件的 二維圖 使零件圖完整同時可以表達清楚零件的結(jié)構(gòu) 1 2 模具裝配草圖 初步完成了模具的裝配草圖 對裝配圖有了一個基本的認識和理解 1 3 外文文獻翻譯 通過工具翻譯了一篇與模具相關(guān)的外文文獻 使自己對國外的模具研究有了一 個認識 1 4 設(shè)計方案 經(jīng)過研究和討論 對設(shè)計方案有了更加完善的結(jié)果 模具采用上下開模的方式 采用一模兩腔的結(jié)構(gòu) 對稱放置 一次成型 澆注采用側(cè)澆口 同時澆注 由于該 塑件上具有與開模方向不一致的孔 所以要設(shè)計側(cè)向抽芯機構(gòu) 在開模的同時進行 側(cè)向抽芯 同時也需要脫模機構(gòu) 在開模后將塑件頂出 在定模和動模之間要有導(dǎo) 桿 保證動模定模能夠正確的開合 2 存在問題及解決措施 2 1 沒有很好的掌握和理解模具裝配的知識 模具裝配圖存在一些問題 具體的計 算沒有完成 2 2 對注射機的了解還不夠 沒有完成相應(yīng)的計算及校核 同時對塑件和模具的理 解還不到位等 2 3 對模具的側(cè)向抽芯的設(shè)計存在不合理的地方 對側(cè)抽芯機構(gòu)認識和理解不夠深 刻 2 4 模具的流道和澆注設(shè)計做的不夠 缺乏這方面知識的學(xué)習(xí) 接下來的時間里 需要對自己掌握不好的地方重點研究和理解 參考資料對自 己較少涉及的方面重點學(xué)習(xí) 同時要與同學(xué)和老師多溝通交流 進一步加深對模具 設(shè)計的理解以及把所學(xué)的理論知識運用到實際設(shè)計中去 3 后期工作安排 11 12 周 完成注射機的選擇及校核 通過計算逐步完善模具裝配圖 13 15 周 完成模具裝配中所有的零件設(shè)計同時畫出所有零件圖 同時對模具進行 三維剖析 做出模具的開合結(jié)構(gòu)圖 16 17 周 撰寫畢業(yè)論文 18 周 整理資料 準備答辯 指導(dǎo)教師簽字 年 月 日 A technical note on the characterization of electroformed nickel shells for their application to injection molds Universidad de Las Palmas de Gran Canaria Departamento de Ingenieria Mecanica Spain Abstract The techniques of rapid prototyping and rapid tooling have been widely developed during the last years In this article electroforming 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 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 Nickel 1 Introduction One of the most important 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 the 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 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 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 accuracy 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 analyze 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 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 systematized way of use and proposing a working method 2 Manufacturing process of an injection mold The 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 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 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 manufacturing 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 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 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 equipment Electrodeposition 5 and 6 is an electrochemical process in which a chemical 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 current 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 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 obtain 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 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 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 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 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 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 hardness One 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 hardness 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 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 temperature On the other hand the hardness of a conventional sulfamate bath is between 200 250 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 for injection molds it is possible to find steel for improvement 290 HV steel for integral hardening 520 595 HV casehardened steel 760 800 HV etc in such a way that it can be observed that the hardness levels of the nickel shells would be within the medium high range of the materials 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 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 structure In order to 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 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 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 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 indicate 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 density A dm2 1 4 2 0 2 55 2 22 2 3 9 0 2 45 5 56 3 4 0 0 2 45 10 00 4 4 0 0 2 45 22 22 Fig 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 good 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 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 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 above all to the presence of the additives used because a nickel sulfamate bath without additives normally creates a fibrous and non laminar structure 9 The modification until a nearly null value of the wetting agent gave as a result that the laminar structure was maintained in any case that matter demonstrated that the determinant for such structure was the stress reducer Allbrite SLA On the other hand it was also tested that the laminar structure varies according to the thickness of the layer in terms of the current density Fig 6 Plane transversal of series 2 600 etch 2 6 Internal stresses One of the main characteristic that a shell should have for its application like an insert is to have a low level of internal stresses Different tests at different bath temperatures and current densities were done and a measure system rested on cathode flexural tensiometer method was used A steel testing control was used with a side fixed and the other free 160 mm length 12 7 mm width and thickness 0 3 mm Because the metallic deposition is only in one side the testing control has a mechanical strain tensile or compressive stress that allows to calculate the internal stresses Stoney model 10 was applied and was supposed that nickel substratum thickness is enough small 3 m to influence in an elastic point of view to the strained steel part In all the tested cases the most value of internal stress was under 50 MPa for extreme conditions and 2 MPa for optimal conditions an acceptable value for the required application The conclusion is that the electrolitic bath allows to work at different conditions and parameters without a significant variation of internal stresses 7 Test of the injection mold Tests have been carried out with various representative thermoplastic materials such as PP PA HDPE and PC and it has been analysed the properties of the injected parts such as dimensions weight resistance rigidity and ductility Mechanical properties were tested by tensile destructive tests and analysis by photoelasticity About 500 injections were carried out on this core remaining under conditions of withstanding many more In general terms important differences were not noticed between the behavior of the specimens obtained in the core and the ones from the machined cavity for the set of the analysed materials However in the analysis by photoelasticiy Fig 7 it was noticed a different tensional state between both types of specimens basically due to differences in the heat transference and rigidity of the respective mold cavities This difference explains the ductility variations more outstanding in the partially crystalline materials such as HDPE and PA 6 Fig 7 Analysis by photoelasticity of injected specimens For the case of HDPE in all the analysed tested tubes it was noticed a lower ductility in the specimens obtained in the nickel core quantified about 30 In the case of PA 6 this value was around 50 8 Conclusions After consecutive tests and in different conditions it has been checked that the nickel sulfamate bath with the utilized additives has allowed to obtain nickel shells with some mechanical properties acceptable for the required application injection molds that is to say good reproducibility high level of hardness and good mechanical resistance in terms of the resultant laminar structure The mechanical deficiencies of the nickel shell will be partially replaced by the epoxy resin that finishes shaping the core for the injection mold allowing to inject medium series of plastic parts with acceptable quality levels