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PAGE135-教案2012~2013学年第一学期学院(系、部)机电工程学院课程名称理论力学(TheoreticMechanics)授课班级11级本科机械设计(1)&(2)班主讲教师李昌德职称专职教师(校评副教授)使用教材高等教育出版社:《EngineeringMechanics:statics》TenthEditionCompiledby:R.C.Hibbeler机电工程学院课程概况课程名称理论力学-静力学篇(双语教学课程)课程编号总计:48学时讲课:44学时实验:4学时上机:0学时学分3类别必修课(√)选修课()理论课(√)实验课(√)任课教师李昌德职称专职教师(校评副教授)授课对象授课班级:11级统招本科机械设计(1)&(2)班共2个班基本教材和主要参考资料1、授课基本教材(TextBook):高等教育出版社:《EngineeringMechanics:statics》TenthEditionCompiledby:R.C.Hibbeler2、主要参考资料(ReferenceMaterials):△EngineeringMechanics-Statics,A.Bedford,W.Fowler.McGraw-HillPublishingCompany;2001Shames,I.H.andPitarres,J.M.,IntroductiontoSolidMechanics,ThirdEdition,PrenticeHall,2000.http://www.PearsonE;/what.htm教学目的要求针对16周48学时的理论力学-静力学篇(双语教学课程)的教学计划,谨规划选择性的着重于讲授课程的第一部分静力学篇(Statics);其中专业内容包括:1)GeneralPrinciples;2)ForceVector;3)EquilibriumofaParticle;4)ForceSystemResultants;5)Equilibriumofarigidbody;6)StructuralAnalysis;7)InternalForce;8)Friction;9)CenterofGravityandCentroid;10)MomentsofInertia;11)Virtualwork…等专题,规划逐课时44学时依序讲授工程力学-静力学篇,各项有关的科技论述与专业英语词汇,同时,训练学生以此课文内容,作为专业英语的阅读能力培养及实际学习与应用,并尽量配合其他机械(设计、制造)及其自动化之工程系列的专业课程实施系统性、启发式教学;另安排4学时的实验课,使学生能够循序渐进的去了解、熟悉、掌握有关机械工程设计&制造基础原文课程的精髓所在,期能藉此为学生日后出国深造或考研进修实施奠基,且同步学习&研析、查阅&参考国外所出版的期刊&发表的各类专业科技论文。课程讲授的过程主要着重于阐述一般英语词汇在本专业(理论力学)领域中的特殊&正确的用法,使学生培养&产生主动学习的兴趣;更于课间循序为学生补充个别单词&词汇的相关同义词(Synonym),期望借此强化学生的英语Verbal能力,更为日后参加国内高校英语能力CET四六级或国际交流TOEIC考试,以及TOEFL&IELTS&GRE出国留学英语能力测验预先進行奠基,同时打下厚实的科技英语基础,期使本院系学生皆能顺利通过国内各项英语专业考试&测验,并大幅提升学生及格人数的比例。利用参考教材辅导学生认识更多有关机械设计、制造和自动化方面常见的缩略语(Abbreviations),及常用的机械工程技术领域的词首字母缩略组合词(Acronyms)英文应用文体范例,并同步训练学生习惯性去理解、熟悉英语原文课程的科技论述表达方式,且采用渐进与模拟方式自我练习缮写和理论力学学科相关之英文科技论文。让本机电工程学院研习理工科技的绝大部分学生,能够迅速理解&明瞭自身学习双语教学课程的必要性&迫切性;同时,训练&辅导学生由浅入深及结合自身已经学过并理解之中文课程内容,机械/力学/材料科学,以及机械工程与机械相关现代设计/制造技术的基础专业知识,循序渐进的研习机械/材料/数控工程与现代设计/制造技术的专业英语,并在详细阅读和深切体会英文教材内容的学习过程后,能够更深一层的理解及融会贯通所学相关专业知识中,英文原创科技作者的理论精华与实际应用范畴,并尝试体验原汁原味的教材,采用深入学习模式,祈使能更进一步的体会、认识到欧美先进科技与实际应用之真谛;进而将个人置身科技领域的起点,大幅度向前逼近欧美科技先进地区理工科学生的普遍化科技水平,也更能够为国家薪火计划以及新一轮的科技建设队伍贡献新的血轮。为弥补本院学生在校接受高等教育期间,各年级所有的专业课程均未采用原文(英文)教科书(TextBooks)的不足与缺憾,也希望借助此项双语课程的开设,能够启发学生们对于机械设计/理论力学/材料科学,以及机械工程与机械相关现代设计/制造技术相关专业英语的浓厚学习兴趣,并能逐步引导学生自发性的走进图书馆,去查询各学科专业技术英文期刊、参考资料及原文科技杂志,为日后迈入考研及出国留学之路打下厚实的基础。6、讲授理论力学-静力学篇(双语教学课程),首先应予重视下列几点:1)学习理论力学-静力学篇双语教学课程,首重科技英语的熟练,除学习理论力学-静力学篇相关的科技英语专业词汇外,也必须学习日常生活应用相关的普通词汇,而全部“美式英语”惯用语法的知识与技巧,在授课过程中亦当然应该有所侧重;2)在上述理论的基础上,还必须学习一些有关理论力学同类学科的科技专业英语,以及翻译为中文语句方面的基本理念和直译技巧;3)应该要求学生更加关注本课程,除课堂内力求理解教材之内容外,平时应该练习主动的去广泛的接触与理论力学-静力学篇课程相关的各种英文版科技期刊与参考文献。4)课后精选各章节段落附含的综合应用例题与习题,布置学生用心练习,并且记录在作业簿上,作为日后期末考前复习资料的一部分,同时要求学生在做题目时务必严格作图,尤其是“分离体的受力图”,更借此培养学生的机械制图能力。教学重点难点⊙教學重點:1、鉴于理论力学-静力学篇双语教学课程,所使用的专业英语词汇与日常生活会话词汇的迥异性,故针对机械/材料工程与现代机械设计/制造技术相关专业英语的每个教学单元课程,除了阐明物理与数学的概念及表示方式外,均先提示学生一般在中学时期已学习过词汇的特殊用法,令学生在明瞭理论力学的同时对英语产生浓厚的学习兴趣。2、针对原文教材各单元的专业技术之物理及数学表示方式、专用语法和翻译注释,在开始授课前即进行讲解&导读,并对现行有关理论力学-静力学篇与机械/材料工程与现代机械设计/制造技术专业课程,滞后于当今欧、美先进的同类科技展的不足现象进行弥补。3、依照教材课文内容进行段落重点式的讲解,并提示学生关于理论力学-静力学篇的科技性论文&报告的缮写概要模式,同时布置课内重点作业、登记累算个别学生的平时成绩,继而要求学生上课期间抄写随堂笔记,当作课后实际作业以便日后计算平时成绩。4、学期课后考察方式则选采全球先进的英语GRE物理、数学测验模式进行,令学生深感犹如参加CET四-六级考试模拟测试般,进而括大面积、增广范围的吸收机械/材料工程与现代机械设计/制造技术相关专业英语知识,且使自身的英语水平必然相对提升。5、针对机械/材料工程与现代机械设计/制造技术领域相关专业英语中的词首字母缩略组合词(Acronyms)&缩写词(Abbreviation),均给予重点提示和强化记忆疏导,并时常做针对性的讲解,且举例说明词首字母缩略组合词(Acronyms),在专业英语范畴内的实用性及前卫性&特殊性及重要性;让学生在学习过后立即可以运用在“毕业设计”论文中,如此学生的主动学习兴趣自然高涨,积极性也将不断提高。⊙教學難點:1、由于理论力学-静力学篇课程与现代机械设计/制造技术相关的专业英语,所涉及的领域过于广泛,故经常发生因课程内容精辟必须耗时讲解,而致授课时间难以掌控的情形或若对学生疑难多加解释则必延误课程进度的情况时有发生,谨此建议:增加本课程的课时,并将之列为大二年级的必修课程,以便学生能够充分、完整的学习本项专业英语课程。2、授课时将学生一般在初、高中时期已学习过的很多常态英语词汇,技巧性的将其转换为在机械/材料工程与现代机械设计/制造技术领域专业英语中的特殊用法,而于解释过程中,学生往往无法立即明瞭和接受,唯经反复阐述、提示,方能获得初步成效。3、对学生而言,由于其同时学习机械/材料工程与现代机械设计/制造技术的其他相关课程,均采用国内自编中文教材因为部分编者不求甚解的偏颇观念与过时理念,往往对学生造成想当之困扰,使其对例常教学内容与本项课程内容的对应性及配合性极难掌握,造成部分学生在学习专业英语的过程中,仍存有学习不适应与理解冲突等缺憾现象。4、为培养本科学生对本项理论力学-静力学篇“双语教学”课程的学习兴趣,拟建议:针对本院各专业科系的重点课程,均配比增开、实施各科专业的双语教学课程,使学生能逐步自行参照中、英文教材对比研析,如此才能更有效的学习较先进的科技知识及英语语法概念。5、由于当今全球已开发国家均盛行、通用“美式英语”,故欲与国际先进科技接轨,就必须规划全国的莘莘学子,全面展开学习先进的“美式英语”;而目前国内的“大学英语”教学则常年采用“英式英语”作为英文学习教材,以致当学生面对本双语课程的原文教材内容时容易产生困惑,加以国内许多资深的教学“专家”早已自行规整创建了一套“Chinglish”,并且长年累积、持续的灌输学生以错误的英语学习观念&语法意识及词汇用法,也因此造成了本“双语课程”在授课过程中明显出现“双轨脱序”现象,所以务必要求学生全力配合授课老师对本双语教学课程的相关要求,同时付出更多的努力与勤奋,如此学生的学习成效才能逐渐有所斩获。

理论力学-静力学篇(双语教学课程)课程教案授课时间第一周:周一、二第3、4节;周三第5、6节(单周课程)课次11授课方式(请打√)理论课(√)讨论课(√)实验课()习题课()其他()课时安排2hr/次授课题目(教学章、节或主题):第一单元:理论力学-静力学篇总纲概述Unit1:GeneralPrinciples主要教学方法与手段授课模式:理论力学-静力学篇的原理&物理、数学表示法,及课堂面授(VerbalInstruction)、词汇疑惑澄清、专有名词释疑…等。本课次教学之目的、要求(分掌握、熟悉、了解三个层次):原则上采取由浅入深、循序渐进与启发式的教学方式,训练学生针对理论力学-静力学篇的双语课程内容逐步进行:⊙掌握:ThetopicsoftheCourseContentsthese11ChaptersObjectivesinthefieldsofTheoreticMechanics-StaticsandAdvancedEngineeringMechanics.⊙熟悉:EngineeringMechanicsarethoseusedintheApplicationsandbecomefourmainparts:1)Statics;2)Kinematics3)Dynamics&Kinetics;4)MechanicsofMaterials.⊙了解:1、TheApplicationsoftheTheoreticMechanicsare1)MechanicsofMaterials;2)MechanicalPrinciples;3)MachineDesign;4)StructuralMechanics;5)Plastic&ElasticMechanics;6)FluidDynamics;7)FlightMechanics;8)VibrationTheory.2、ScientistsoftenclassifytheResearchModelofTheoreticMechanicsbytheirappearancestates:Solid(RigidBody,noteasytochangetheirshape),Liquid,orgas(Theirshapesarechangeable);andthosekindsofmaterialsalsobeseparatedintodifferentkindoforganicmaterialsandinorganicmaterials.教学重点及难点:⊙教学重点:IntroductiontoTheoreticMechanicsandAdvancedEngineeringMechanics,whichthathastoinclude:1)ThedefinitionofMechanicalmotion:thesituationofmatterinSpacewaschangedwithrespectivetothevariabletime;2)BasicQnantities:Length、Time、Mass、Force;3)IdealizationstotheModels;4)SignificantParticles;5)TheApplicationofRigidBody;6)ConcentratedForce;7)Newton’sThreeLawsofmotion;8)Newton’sLawofGravitationalAttraction;9)TheMathematicalDerivationsoftheWeightandtheGravitationalForce;10)UnitsofMeasurement:SIUnits(TheInternationalSystemofUnits)&U.S.CustomaryandRulesforUse;11)NumericalCalculationsincluding:1)DimensionalHomogeneity;2)SignificantFigures(Digits);3)RoundingoffNumbers.⊙教学难点:1.1)IntroductiontothePropertiesofTheoreticMechanics,1.2)IntroductiontotheTheFundamentalConceptsofStaticsintheTheoreticMechanics,1.3)IntroductiontotheTheUnitsofMeasurements教学基本内容及过程周一、二第3、4节(两班共同授课内容)IntroductiontoEngineeringMaterialsarethoseusedinmanufactureandbecomepartsofproductsshouldbefurthersubdividedinto1)Metals;2)Ceramics;3)Composite;4)Polymers;etc.2、IntroductiontoNonengineeringmaterialsarethechemicals,fuels,lubricants;andothermaterialsusedinthemanufacturingprocess,butwhichdonotbecomepartoftheproductetc.3、Introductiontothespecialelementswithinakindofceramicsmaterials,otherthentheporcelain;chinaclay;potter’searth;etc.especially,emphasistohinttheglobalfocusandthetreasureofourcountry:whichistheREE(RareEarthElement).(Phase-Ⅰ)4、Metalalloysincludestainlesssteelwhichisanalloyofiron,nickel,andgoldjewelrywhichusuallycontainsanalloyofgoldandnickel;Alloysarecompoundsconsistingofmorethanonemetal.Addingothermetalscanaffectthedensity,strength,fracturetoughness,plasticdeformation,electricalconductivityandenvironmentaldegradation.5、Somemetalalloys,suchasthosebasedonaluminum,havelowdensitiesandareusedinaerospaceapplicationsforfueleconomy.6、Itisimpossibletoseethroughmetals,sincethesevalenceelectronsabsorbanyphotonsoflight,whichreachthemetal.7、Someoftheusefulpropertiesofceramicsandglassesincludehighmeltingtemperatures,lowdensity,highstrength,stiffness,hardness,wearresistanceandcorrosionresistance.8、Anopticalfibercontainsthreelayers:acoremadeofhighlypureglasswithahighrefractiveindexforlighttotravel,amiddlelayerofglasswithalowerrefractiveindexknownasthecladdingwhichprotectsthecoreglassfromscratchesandothersurfaceimperfections,andanouterpolymerjackettoprotectthefiberfromdamage.9、Particles-reinforcedComposites:Particlesareusedtoincreasethemodulusofthematrix,todecreasethepermeabilityofthematrix,todecreasetheductilityofthematrix.Suchasanexampleofparticles-reinforcedcompositesisanautomobiletirewhichhascarbonblackparticlesinamatrixofpolyisobutylene(聚异乙/丁烯)elastomericpolymer.Particlesusedforreinforcingincludeceramicsandglassessuchassmallmineralparticles,metalparticlessuchasaluminum,andamorphousmaterials,includingpolymersandcarbonblack.10、Importantcharacteristicsofpolymers:1)size;singlepolymermoleculestypicallyhavemolecularweightsbetween10,000and1,000,000g/molthatcanbemorethan2,000repeatingunitsdependingonthepolymerstructure.Theothersomeimportantcharacteristicsofpolymersincludetheirsize(ormolecularweight),softeningandmeltingpoints,crystallinity(结晶度),andstructure;Themechanicalpropertiesofpolymersgenerallyincludelowstrengthandhightoughness;Theirstrengthisoftenimprovedusingreinforcedcompositestructures.11、Importantcharacteristicsofpolymers:1)size;2)thermaltransitions;3)Crystallinity;4)Interchaininteractions(链间相互作用);5)Interchainstructure(thechemicalstructureofthechains).12、Reinforcingfiberscanbemadeofmetals,ceramics,glasses,orpolymersthathavebeenturnedintographiteandknownascarbonfibers,Fibersincreasethemodulusofthematrixmaterial.Thestrongcovalentbondsalongthefiber’slengthgivethemaveryhighmodulusinthisdirectionbecausetobreakorextendthefiberandthebondsmustalsobebrokenormoved.教学基本内容及过程周三第5、6节〖(2)班单周授课内容〗作业和思考题:依照《理论力学-静力学篇》原文教材的英文课文进行段落重点式讲解,并提示及灌输学生科技性英文论文&报告的缮写概要与模式;同时,采取抽点学生方式提问,进行彼此互动式交流作答,并布置课本内随堂作业、分别登记累算个别学生的平时作业成绩,继而强烈要求学生在上课期间,根据听课重点抄写随堂笔记,其撰写笔记内容的丰简,将列为其课后实际作业评比的标准,以便日后累加计算平时成绩。课后小结:1)建议:本项“理论力学-静力学篇”双语教学课程应配合“大学普通物理“、“高等数学”与“线性代数”、“大学英语”及“专业英语”等课程的进度,合并提前开设;让学生能够自入学大一起始就接受“双轨制”全面“美式英语”相关双语教学,同时,可针对各科系专业的实际需求,自大学一、二年级起,即择优片面开设:微积分、工程数学、普通物理、普通化学、工程力学、线性代数、计算机基本原理…等基础学科与科系的专业学科之“专业英语”课程,俟全院两届本科学生整体学习后,再针对学生的受教程度及英语水平进行全面评估,如此进行深度化教学整改后,相信本院系全体老师的其他相关专业学科的普遍教学品质与学生自身的整体素质亦将获得同步提升。2)学生整体到课比率&上课学习情绪现阶段皆属积极,且针对先进“美式英语”教学的课程内容充满了求知的兴趣,相信凡是愿意主动投入心力学习的学生,相信无论是在个人英语程度、造诣方面和在理论力学及工程力学与材料力学和现代机械设计、模具制造技术等领域之双语教学课程专业知识的学习成效方面,必然将会逐步明显提升并间接获得显著的学习成果。3)由于当今全球已开发国家均盛行、通用“美式英语”,故欲与国际先进科技接轨,就必须规划全国的莘莘学子,全面展开学习先进的“美式英语”;而目前国内的“大学英语”教学则常年采用“英式英语”作为英文学习教材,以致当学生面对本双语课程的原文教材内容时容易产生困惑,加以国内许多资深的教学“专家”早已自行规整创建了一套中式的英式英语“Chinglish”,并且长年累积、持续的灌输学生以错误的英语学习观念&语法意识及词汇用法,也因此造成了本“双语课程”在授课过程中明显出现“双轨脱序”现象,所以务必要求学生全力配合授课老师对本《理论力学-静力学篇》双语教学课程的相关要求,同时付出更多的努力与勤奋,如此学生的学习成效才能逐渐有所斩获。理论力学-静力学篇(双语教学课程)课程教案授课时间第二周:周一、二第3、4节;周三第5、6节(双周课程)课次22授课方式(请打√)理论课(√)讨论课(√)实验课()习题课()其他()课时安排2hr/次授课题目(教学章、节或主题):第二单元:金属工程材料的热处理Unit2:HeatTreatmentofMetals主要教学方法与手段授课模式:课堂面授(VerbalInstruction)、词汇疑惑澄清、专有名词释疑…等本课次教学之目的、要求(分掌握、熟悉、了解三个层次):原则上采取由浅入深、循序渐进的教学方式,训练学生针对课程的内容逐步进行:⊙掌握:1、Theunderstandingofheattreatmentisembracedbythebroaderstudyofmetallurgy.2、Metallurgyisthephysics,chemistry,andengineeringrelatedtometalsfromoreextractiontothefinalproduct.3、Heattreatmentistheoperationofheatingandcoolingametalinitssolidstatetochangeitsphysicalproperties.4、Withtheproperheattreatmentinternalstressesmayberemoved,grainsizereduced,toughnessincreased,orahardsurfaceproducedonaductileinterior.⊙熟悉:1、Steelcanbehardenedtoresistcuttingactionandabrasion,oritcanbesoftenedtopermitmachining.2、Alloysteelsowetheirpropertiestothepresenceofoneormoreelementsotherthancarbon,namelynickel,chromium,manganese,molybdenum,tungsten,silicon,vanadium,andcopper;Sincetheirimprovedphysicalpropertiestheyareusedcommerciallyinmanywaysnotpossiblewithcarbonsteels.⊙了解:1、Whenalloysarecooledrapidly,entirelydifferentresultsmaybeobtained,becausesufficienttimeisnotprovidedforthenormalphasereactionstooccur.2、Proceduresofheattreatmentofmetalsincluding:1)Hardening;2)Tempering;3)Annealing;4)NormalizingandSpheroidizing.3、ProcessesofSurfaceHardeningincluding:1)Carburizing;2)Carbonitriding;3)Cyaniding;4)Nitriding.教学重点及难点:⊙重点:1、Introductiontotheheattreatmentofmetals,andtheSimplifiedIron-CarbonDiagramwhichthatisoftenused.2、Theunderstandingofheattreatmentisembracedbythebroaderstudyofmetallurgy.3、IntroductiontotheProceduresofheattreatmentofmetalswhichthatincluding:1)Hardening;2)Tempering;3)Annealing;4)NormalizingandSpheroidizing.4、Aceramicisoftenbroadlydefinedasanyinorganicnonmetallicmaterial.Bythisdefinition,ceramicmaterialswouldalsoincludeglasses;however,manymaterialsscientistsaddthestipulationthat"ceramics"mustalsobecrystalline.⊙难点:1、Steelcanbehardenedtoresistcuttingactionandabrasion,oritcanbesoftenedtopermitmachining;2、Proceduresofheattreatmentofmetalsincluding:1)Hardening;2)Tempering;3)Annealing;4)NormalizingandSpheroidizing;3、ProcessesofSurfaceHardeningincluding:1)Carburizing;2)Carbonitriding;3)Cyaniding;4)Nitriding;4、Alloysteelsowetheirpropertiestothepresenceofoneormoreelementsotherthancarbon,namelynickel,chromium,manganese,molybdenum,tungsten,silicon,vanadium,andcopper;Sincetheirimprovedphysicalpropertiestheyareusedcommerciallyinmanywaysnotpossiblewithcarbonsteels.教学基本内容及过程1、IntroductiontotheMetalTreatingMethodsoftheHeatTreatmentofMetalswhichbeusedintheProceduresofheattreatmentofmetalswhichthatincluding:1)Hardening;2)Tempering;3)Annealing;4)NormalizingandSpheroidizing;2、Alloysteelsowetheirpropertiestothepresenceofoneormoreelementsotherthancarbon,namelynickel,chromium,manganese,molybdenum,tungsten,silicon,vanadium,andcopper;Sincetheirimprovedphysicalpropertiestheyareusedcommerciallyinmanywaysnotpossiblewithcarbonsteels.3、Introductiontothespecialelementswithinakindofceramicsmaterials,otherthenthemica;quartz;glass;silicon;porcelain;chinaclay;potter’searth;etc.especially,Let’semphasistohinttheglobalfocusandthetreasureofourcountry:theREE(RareEarthElement).(Phase-Ⅱ)4、Thoseportionsoftheiron-carbondiagramnearthedeltaregionandthoseabove2%carboncontentareoflittleimportancetotheengineerandaredeleted.Note:thesolidsolution固溶体状态;thedeltaregion:铁素体区5、TheironwantstochangefromtheFCC(FaceCenteredCubic)austenitestructuretotheBBC(BodyCenteredCubic)ferritestructure,buttheferritecanonlycontain0.02%carboninsolidsolution.6、Itisimpossibletoseethroughmetals,sincethesevalenceelectronsabsorbanyphotonsoflight,whichreachthemetal;ingeneral,whileprocessingelectrolysisreactionthemetalsareopaqueoradiaphanousandsotheotherelectrodemustbetransparentintheelectrolyticcell.7、Thisstructureofthelamellarstructureofalternatingplatesthatformsonslowcooling,iscomposedoftwodistinctphases,buthasitsownsetofcharacteristicpropertiesandgoesbythenamepearlite,becauseofitsresemblancetomother-of-pearlatlowmagnification.8、Tie-lineandlever-lawcalculationsshowthatlow-carbonferritenucleatesandgrowsleavingtheremainingaustenitericherincarbon.9、TheProceduresofheattreatmentofmetalswhichthoseincluding:1)Hardening:theprocessofheatingapieceofsteeltoatemperaturewithinoraboveitscriticalrangeandthencoolingrapidly;andinanyheat-treatingoperationtherateofheatingisimportant.2)Tempering:Itispossiblebecauseoftheinstabilityofthemartensite,theprincipalconstituentofhardenedsteel;theoperationconsistofreheatingquench-hardenedsteeltosometemperaturebelowthecriticalrangefollowedbyanyrateofcooling,thefinalstructureobtainedfromtemperingfullyhardenedsteeliscalledtemperedmartensite.3)Annealing:Theprimarypurposeofthisprocedureistosoftenhardsteelsothatmaybemachinedorcoldworked;thisprocessisknownasfullannealingbecauseitwipesoutalltraceofpreviousstructure,refinesthecrystallinestructure,andsoftensthemetal.4)NormalizingandSpheroidizing:Theprocessofnormalizingconsistsofheatingthesteelabout10℃to40℃uppercriticalrangeandcoolinginstillairtoroomtemperature;Thatisprincipallyusedwithlow-andmedium-carbonsteelsaswellasalloysteelstomakethegrainstructuremoreuniform,torelieveinternalstresses,ortoachievedesiredresultsinphysicalproperties;mostcommercialsteelsarenormalizedafterbeingrolledorcast.10、TheprocessesofSurfaceHardeningwhichinclude:1)Carburizing(渗碳法):thecarbonisabsorbedintothemetaltoformasolidsolutionwithironandconvertstheoutersurfaceintohigh-carbonsteel,thecarbonisgraduallydiffusedtotheinteriorofthepart;steelforcarburizingisusuallyalow-carbonsteelofabout0.15%carbonthatwouldnotinitselfrespondsappreciablytoheattreatment.2)Carbonitriding:It,sometimesalsoknownasdrycyanidingornicarbing,isacase-hardeningprocessinwhichthesteelisheldatatemperatureabovethecriticalrangeinagaseousatmospherefromwhichitabsorbscarbonandnitrogen;anycarbon-richgaswithammoniacanbeused.3)Cyaniding:thatorliquidcarbonitridingasitissometimescalled,isalsoaprocessthatcombinestheabsorptionofcarbonandnitrogentoobtainsurfacehardnessinlow-carbonsteelsthatdonotrespondtoordinaryheattreatment;theparttobecasehardenedisimmersedinabathoffusedsodiumcyanidesaltsatatemperatureslightlyabovetheAc1range,thedurationofsoakingdependingonthedepthofthecase.4)Nitriding:Itissomewhatsimilartoordinarycasehardening,butitusesadifferentmaterialandtreatmenttocreatethehardsurfaceconstituents;inthisprocessthemetalisheatedtoatemperatureofaround510℃andthereforaperiodoftimeincontactwithammoniagas;nitrogenfromthegasisintroducedintothesteel,formingveryhardnitridesthatarefinelydispersedthroughthesurfacemetal.11、Nitrogenhasgreaterhardeningabilitywithcertainelementsthanwithothers,hence,specialnitridingalloysteelshavebeendeveloped;thetemperatureofheatingrangesfrom495℃to565℃and,asingasnitriding,thetemperatureisheldbelowthetransformationrange,liquidnitridingaddsmorenitrogenandlesscarbonthaneithercyanidingorcarburizingincyanidebaths.作业和思考题:1、依照教材中各章节内的英文课文进行段落、重点式讲解,并提示&灌输学生学习、练习撰写科技英文论文&报告的缮写理念、摘要&模式。2、对学生采取点名抽样方式提问,进行彼此互动式交流问答,并布置简单随堂作业、并分别登记累算个别学生的平时作业成绩,继而强力要求学生于上课期间抄写随堂笔记,视同为课后实际作业以便日后累计合算平时成绩。3、针对课程进度与下周授课内容布置学生预习教材范围,另外,指定相关专业英文词汇,让学生课前/后&预习/复习,练习查阅同义词汇(Synonyms),以期培养学生主动&正确&良好的“美式英语”&“专业英语”之学习方法&思维逻辑。4、讲授机械工程专业英语课程,首先应予重视下列三点:1)学习科技英语,除学习科技专业词汇,也必须学习相关普通词汇和全部“美式英语”的语法知识,当然应该有所侧重;2)在第一条的基础上,还必须学习一些有关科技英语翻译为中文方面的理论与技巧;3)此外,还应该多接触科技资料的各种英文版参考文献。课后小结:1、学生整体到课比率&上课学习情绪皆属高昂,且针对先进“美式英语”之专业英语课程的内容,充满了求新、求知、求精、求实的学习兴趣。2、相信凡是愿意主动投入心力学习的学生,无论是在个人英语造诣方面以及在机械&材料工程与机械&模具制造技术领域专业英语的学习方面,必然将会逐步有所斩获。3、建议:本项“专业英语”课程应配合普通“大学英语”课程并提前开设,让学生自入学起始就接受“双轨制”全面“美式英语”相关教学,同时,可针对各科系的需求,自大学一、二年级起,即择优片面开设:微积分、工程数学、普通物理、普通化学、工程力学、计算机基原理…等基础学科与科系的专业学科之“专业英语”课程,俟全院两届本科学生学习后,再对学生的英语程度进行全面评估,如此,则本院系的其他相关专业学科的普遍教学品质学生整体素质亦将获得同步提升。4、由于当今全球已开发国家均盛行“美式英语”,故欲与国际先进科技接轨,就必须规划全国的莘莘学子,全面展开学习先进的“美式英语”;而目前国内的英语教学则常年采用“英式英语”作为教材,以致当学生面对本课程的教材内容时容易产生困惑与障碍,加以国内许多教学“专家”早已自行规整创建了一套“Chinglish”,并且长年累积、持续的灌输学生以错误的英语学习观念&语法意识及词汇用法,也因此造成了本课程在授课过程中明显的出现“双轨脱序”现象,所以务必要求学生全力配合授课老师对课程的相关要求,同时付出更多的努力,学习才能逐渐有所斩获。材料成型(MaterialsMolding)专业英语课程教案授课时间第三周周三第3、4节课次3授课方式(请打√)理论课(∨)讨论课(∨)实验课□习题课(∨)其他□课时安排2hr授课题目(教学章、节或主题):第三单元:金属铸造过程Unit3:CastingProcesses主要教学方法与手段授课模式:课堂面授(VerbalInstruction)、词汇疑惑澄清、专有名词释疑…等本课次教学之目的、要求(分掌握、熟悉、了解三个层次):原则上采取由浅入深、循序渐进的教学方式,训练学生针对课程内容逐步进行:⊙掌握:Castingisamanufacturingprocessinwhichmoltenmetalispouredorinjectedandallowedtosolidifyinasuitablyshapedmoldcavity;duringoraftercooling,thecastpartisremovedfromthemoldandthenprocessedfordelivery.⊙熟悉:Castingprocessesandcast-materialtechnologiesvaryfromsimpletohighlycomplex;materialandprocessselectiondependsonthepart’scomplexityandfunction,theproduct’squalityspecifications,andtheprojectedcostlevel.⊙了解:Castingsarepartsthataremadeclosetotheirfinaldimensionsbyacastingprocess;withahistorydatingback6,000years,thevariouscastingprocessesareinastateofcontinuousrefinementandevolutionastechnologicaladvancesarebeingmade.教学重点及难点:⊙重点:1、Introductiontothedifferentkindsofcastingprocesses,atwhichthatincludes:1)SandCasting;2)InvestmentCasting;3)CentrifugalCasting.2、Theunderstandingofvariouskindsofvariablecast-materialTechnologiesfromsimpletohighlycomplex,especially,theInvestmentCasting,itcanbeusedtomakepartsthatcannotbeproducedbynormalmanufacturingtechniques,suchasturbinebladesthathavecomplexshapes,orairplanepartsthathavetowithstandhightemperatures.3、IntroductiontotheProceduresoftheInvestmentCasting,themoldofInvestmentCastingprocessismadebymakingapatternusingwaxorsomeothermaterialthatcanbemeltedaway;andthiswaxpatternisdippedinrefractoryslurry,whichcoatsthewaxpatternandformsaskin;waitingthisisdriedandtheprocessofdippingintheslurryanddryingisrepeateduntilarobustthicknessisachieved.⊙难点:1、Thematerialsusedfortheslurryareamixtureofplaster,abinderandpowderedsilica,arefractory,forlowtemperaturemelts;2、Forhighertemperaturemelts,sillimaniteoralumina-silicateisusedasarefractory,andsilicaisusedasabinder;3、Dependingonthefinenessofthefinishdesiredadditionalcoatingsofsillimaniteandethylsilicatemaybeapplied;4、Alloysteelsowetheirpropertiestothepresenceofoneormoreelementsotherthancarbon,namelynickel,chromium,manganese,molybdenum,tungsten,silicon,vanadium,andcopper;Sincetheirimprovedphysicalpropertiestheyareusedcommerciallyinmanywaysnotpossiblewithcarbonsteels;5、Themoldthusproducedcanbeuseddirectlyforlightcastings,orbereinforcedbyplacingitinalargercontainerandreinforcingitmoreslurry;6、Thepourinthepre-heatedmoldalsoensuresthatthemoldwillfillcompletely;Pouringcanbedoneusinggravity,pressureorvacuumconditions;attentionmustbepaidtomoldpermeabilitywhenusingpressure,toallowtheairtoescapeasthepourisdone.教学基本内容及过程1、IntroductiontotheInvestmentcastingMethods,thatisalsoknownasthelostwaxprocess;thisprocessisoneoftheoldestmanufacturingprocesses;theEgyptiansuseditinthetimeofthePharaohstomakegoldjewelry(hencethenameInvestment);2、Withrespecttothisunit:theAcronyms(词首字母缩略组合词)&Abbreviation(缩写词)willbeselectedasfollows:LASER:LightAmplificationbyStimulatedEmissionofRadiationRADAR:RAdioDetectionAndRangingAI:ArtificialIntelligenceAGV:AutomaticGuidedVehicleAPT:AutomaticallyProgrammingToolsmoreelementsotherthancarbon,namelynickel,chromium,manganese,molybdenum,tungsten,silicon,vanadium,andcopper;Sincetheirimprovedphysicalpropertiestheyareusedcommerciallyinmanywaysnotpossiblewithcarbonsteels.3、Introductiontothespecialelements,whichexistwithinsomekindofceramicsmaterials,otherthenthemica;quartz;glass;silicon;porcelain;chinaclay;potter’searth;etc.especially,Let’semphasistohinttheglobalfocusandthetreasureofourcountry:theREE(RareEarthElement),whichwilljointhehigh-temperature&low-temperaturesuperconductivematerials,andthatwasassuredtomakethethirdglobalindustrialrevolutionforthefurtherfuture.(Phase-Ⅲ)4、Introductiontothedifferentkindsofcastingprocesses,atwhichthatincludes:1)SandCasting;2)InvestmentCasting;3)CentrifugalCasting.5、Castingsarepartsthataremadeclosetotheirfinalshapes&dimensionsbyacastingprocess;withahistorydatingback6,000years,thevariouscastingprocessesareinastateofcontinuousrefinementandevolutionastechnological&modernadvancesarebeingmade.6、Sandcastingisusedtomakelargeparts(typicallyiron,butalsobronze,brass,aluminum);Moltenmetalispouredintoamoldcavityformedoutofsand(naturalorsynthetic);theprocessesofsandcastingarediscussedinthissection,including:patterns,spruesandrunners,positionofcavity,designconsiderations,andcastingallowance.7、Thecavityinthesandisformedbyusingapattern(anapproximateduplicateoftherealpart),whicharetypicallymadeoutofwood,sometimesmetal;Thecavityiscontainedinanaggregatehousedinaboxcalledtheflask.8、Coreisasandshapeinsertedintothemoldtoproducetheinternalfeaturesofthepartsuchasholesorinternalpassagesatwhichcoresareplacedinthecavitytoformholesofthedesiredshapes.9、Ingeneral,typicalstagesofsandcastingoperationincluding:1)Patternsaremade;thesewillbetheshapeusedtoformthecavityinthesand.2)Corealsomaybemadeatthistime;thesecoresaremadeofbondedsandthatwillbebrokenoutofthecastpartafteritiscomplete.3)Sandismulled(mixed)thoroughlywithadditivessuchasbentonitetoincreasebondingandoverallstrength.4)Sandisformedaboutthepatterns,andgates,runners,risers,ventsandpouringcupsareaddedasneeded;acompactionstageistypicallyusedtoensuregoodcoverageandsolidmolds.5)Thepatternsareremoved,andthemoldsmaybeputthroughabakingstagetoincreasetheirstrength.6)Moldhalvesarematedandpreparedforpouringmetal.7)Metalispreheatedinafurnaceorcrucibleuntilisabovetheliquidustemperatureinasuitablerange,andwedon’twantthemetalsolidifyingbeforethepouriscomplete.8)Themetalispouredslowly,butcontinuouslyintothemolduntilthemoldisfull.9)Asthemoltenmetalcools(minutestodays),themetalwillshrinkandthevolumewilldecrease;duringthistimemoltenmetalmaybackflowfromthemoltenriserstofeedthepartandmaintainthesameshape.10)Oncethepartstartstosolidifysmalldendritesofsolidmaterialforminthepart;duringthistimethepropertiesofmetalarebeingd

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