【正文】 these will be the shape used to form the cavity in the sand. 2) Core also may be made at this time。 modern advances are being made. Sand casting is used to make large parts (typically iron, but also bronze, brass, aluminum)。 2)Investment Casting。 china clay。 quartz。 the Egyptians used it in the time of the Pharaohs to make gold jewelry (hence the name Investment)。 The pour in the preheated mold also ensures that the mold will fill pletely。 Depending on the fineness of the finish desired additional coatings of sillimanite and ethyl silicate may be applied。 3)Centrifugal Casting. The understanding of various kinds of variable castmaterial Technologies from simple to highly plex, especially, the Investment Casting, it can be used to make parts that cannot be produced by normal manufacturing techniques, such as turbine blades that have plex shapes, or airplane parts that have to withstand high temperatures. Introduction to the Procedures of the Investment Casting, the mold of Investment Casting process is made by making a pattern using wax or some other material that can be melted away。 during or after cooling, the cast part is removed from the mold and then processed for delivery. ⊙ 熟悉： Casting processes and castmaterial technologies vary from simple to highly plex。 建議：本項(xiàng)“專業(yè)英語”課程應(yīng)配合普通“大學(xué)英語”課程并 提前開設(shè)，讓學(xué)生自入學(xué)起始就接受“雙軌制”全面“美式英語”相關(guān)教學(xué)，同時(shí)，可針對(duì)各科系的需求，自大學(xué)一、二年級(jí)起，即擇優(yōu)片面開設(shè)：微積分、工程數(shù)學(xué)、普通物理、普通化學(xué)、工程力學(xué)、計(jì)算機(jī)基原理 ?等基礎(chǔ)學(xué)科與科系的專業(yè)學(xué)科之“專業(yè)英語”課程，俟全院兩屆本科學(xué)生學(xué)習(xí)后，再對(duì)學(xué)生的英語程度進(jìn)行全面評(píng)估，如此，則本院系的其他相關(guān)專業(yè)學(xué)科的普遍教學(xué)品質(zhì)學(xué)生整體素質(zhì)亦將獲得同步提升。上課學(xué)習(xí)情緒皆屬高昂，且針對(duì)先進(jìn) “美式英語 ”之專業(yè)英語課程的內(nèi)容 ， 充滿了 求新、 求知、求精、求實(shí)的 學(xué)習(xí) 興趣。 “專業(yè)英語”之學(xué)習(xí)方法 amp。 針對(duì)課程 進(jìn)度與下周授課內(nèi)容布置學(xué)生預(yù)習(xí)教材范圍，另外，指定 相關(guān)專業(yè)英文詞匯，讓學(xué)生課前 /后 amp。 灌輸 學(xué)生 學(xué)習(xí)、練習(xí)撰寫 科技 英文 論文 amp。 the part to be case hardened is immersed in a bath of fused sodium cyanide salts at a temperature slightly above the Ac1 range, the duration of soaking depending on the depth of the case. 4)Nitriding: It is somewhat similar to ordinary case hardening, but it uses a different material and treatment to create the hard surface constituents。 That is principally used with low and mediumcarbon steels as well as alloy steels to make the grain structure more uniform, to relieve internal stresses, or to achieve desired results in physical properties。 in general, while processing electrolysis reaction the metals are opaque or adiaphanous and so the other electrode must be transparent in the electrolytic cell. This structure of the lamellar structure of alternating plates that forms on slow cooling, is posed of two distinct phases, but has its own set of characteristic properties and goes by the name pearlite, because of its resemblance to motherofpearl at low magnification. Tieline and leverlaw calculations show that lowcarbon ferrite nucleates and grows leaving the remaining austenite richer in carbon. The Procedures of heat treatment of metals which those including: 1)Hardening: the process of heating a piece of steel to a temperature within or above its critical range and then cooling rapidly。 porcelain。 Since their improved physical properties they are used mercially in many ways not possible with carbon steels. Introduction to the special elements within a kind of ceramics materials, other then the mica。 2) Tempering。 3） Cyaniding。 3)Annealing。 4)Normalizing and Spheroidizing. A ceramic is often broadly defined as any inanic nonmetallic material. By this definition, ceramic materials would also include glasses。 3） Cyaniding。 2) Tempering。 3) 由于當(dāng)今全球 已開發(fā)國家均 盛行 、通用 “美式英語 ”， 故欲與國際先進(jìn)科 技 接軌，就必須規(guī)劃全國的 莘 莘學(xué)子，全面展開學(xué)習(xí)先進(jìn)的 “美式英語 ”； 而 目前 國內(nèi)的 “大學(xué) 英語 ” 教學(xué) 則 常年采用 “英式英語 ”作為英文學(xué)習(xí) 教 材，以致 當(dāng) 學(xué)生面對(duì) 本雙語課程的原文 教材內(nèi)容時(shí) 容易產(chǎn)生 困惑，加以 國內(nèi) 許多資深的教學(xué)“ 專家 ”早已 自行 規(guī)整 創(chuàng) 建了一套 中式的英式英語 “Chinglish”，并且長年累積、持續(xù)的 灌輸學(xué)生 以 錯(cuò)誤的英語 學(xué)習(xí) 觀念 amp。報(bào)告的繕寫概要 與 模式 ； 同時(shí) ，采 取抽點(diǎn)學(xué)生方式提問，進(jìn)行彼此互動(dòng)式交流作答，并 布置 課本內(nèi) 隨堂 作 業(yè)、 分別 登記累算個(gè)別學(xué)生的平時(shí) 作業(yè) 成績，繼而 強(qiáng)烈 要求學(xué)生 在 上課 期間 ，根據(jù)聽課重點(diǎn) 抄寫隨堂筆記， 其撰寫 筆記 內(nèi)容 的 豐簡 ， 將列為 其 課后實(shí)際作業(yè) 評(píng)比的標(biāo)準(zhǔn) ， 以便日后 累加 計(jì)算平時(shí)成績。 2)thermal transitions。 Alloys are pounds consisting of more than one metal. Adding other metals can affect the density, strength, fracture toughness, plastic deformation, electrical conductivity and environmental degradation. Some metal alloys, such as those based on aluminum, have low densities and are used in aerospace applications for 9 fuel economy. It is impossible to see through metals, since these valence electrons absorb any photons of light, which reach the metal. Some of the useful properties of ceramics and glasses include high melting temperatures, low density, high strength, stiffness, hardness, wear resistance and corrosion resistance. An optical fiber contains three layers: a core made of highly pure glass with a high refractive index for light to travel, a middle layer of glass with a lower refractive index known as the cladding which protects the core glass from scratches and other surface imperfections, and an outer polymer jacket to protect the fiber from damage. Particlesreinforced Composites: Particles are used to increase the modulus of the matrix, to decrease the permeability of the matrix, to decrease the ductility of the matrix. Such as an example of particlesreinforced posites is an automobile tire which has carbon black particles in a matrix of polyisobutylene (聚異乙 /丁烯 ) elastomeric polymer. Particles used for reinforcing include ceramics and glasses such as small mineral particles, metal particles such as aluminum, and amorphous materials, 10 including polymers and carbon black. Important characteristics of polymers: 1)size。 and other materials used in the manufacturing process, but which do not bee part of the product etc. Introduction to the special elements within a kind of