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塑料模具外文翻譯---關(guān)于電鑄鎳殼在注塑模具中應(yīng)用的技術(shù)研究-模具設(shè)計-資料下載頁

2025-05-12 12:34本頁面

【導(dǎo)讀】本文將對如何使用電芯作為重要核心問題對有關(guān)注塑模具進(jìn)行分析總結(jié)。產(chǎn)電鑄設(shè)備的外殼.此外檢驗注塑模具是最后的一個關(guān)鍵部分.還有很多關(guān)于產(chǎn)品種類和更新?lián)Q代的問題。所以說,現(xiàn)代工業(yè)一定會有更多的。另外,讓時間與質(zhì)量完美的結(jié)合起來并不容易。快速模具制造技術(shù)基本上是一個中小型系列的收集程序,在。很短的時間內(nèi)在可接受的精度水平基礎(chǔ)上讓我們獲得模具的塑料部件。用不僅在更加廣闊而且生產(chǎn)也不斷增多。殼,同時作為一個初始模型的原型在一個FDM設(shè)備上的快速成型。表卓華組織3167標(biāo)準(zhǔn)。這樣做的目的是確定力學(xué)性能的材料收集代表行業(yè)。注塑成型是世界上最常見的方法生產(chǎn)復(fù)雜。注塑成型稱為最重要的制造業(yè)之一。灌漿階段就是在注射溫度下用融解的熱塑料注入模腔。在冷卻期間產(chǎn)品模腔附近也會存在溫度不均勻。溫差會造成材料的不均勻收縮從而產(chǎn)生熱應(yīng)力。表使用劑氯化鎳,有利于解決金屬統(tǒng)一分布在陰極產(chǎn)生的導(dǎo)電性的問題。

  

【正文】 dified. 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 PME3ADL /10. Before going on to ment 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 天津科技大學(xué)外文資料翻譯 20 mm in diameter which is pacted 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 (176。C) Current density (A/dm2) 1 177。 55 2 177。 45 3 177。 45 4 177。 45 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 2176。 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 position. Fig. 3. Series 1 (150), etch 1. 天津科技大學(xué)外文資料翻譯 21 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 nonlaminar 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. 天津科技大學(xué)外文資料翻譯 22 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, mm width and thickness mm). Because the metallic deposition is only in one side the testing control has a mechanical strain (tensile or pressive stress) that allows to calculate the internal stresses. Stoney model [10] was applied and was supposed that nickel substratum thickness is enough small (3 μm) 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 天津科技大學(xué)外文資料翻譯 23 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
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