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机械与动力工程学院文件机字20067号机械与动力工程学院本科生毕业设计 (论文)管理办法 (试行)毕业设计 (论文)是教学计划中最重要的实践性教学环节之一。它的基本要求是培养学生综合运用所学的基础理论、基本知识和基本技能,用以分析、解决工程、科研、社会实际问题的能力使学生得到工程设计方法和科研能力的初步训练。同时培养学生正确的思想方法,树立严谨的治学态度、理论联系实际的工作作风。为加强对毕业设计 (论文)工作的管理,根据学校本科毕业设计管理办法,结合机械与动力工程学院实际情况,特制定本管理办法。 一、毕业设计 (论文)的管理 全院毕业设计 (论文)工作,在主管院长的领导下全面组织管理。为加强对毕业设计 (论文)工作的领导,学院成立由主管院长任组长、专业系(教研室)主任任付组长、教学秘书、专业系(教研室)副主任为成员的毕业设计 (论文)领导小组,负责毕业设计的具体工作。 二、对选题的要求 选题在满足教学要求的前提下要有一定的深度和难度。要注意新技术、新工艺、新方法的应用和训练,加强对学生的计算、绘图、实验、计算机技术等技能的训练。结合生产、科研以及实验室建设的实际题目应达80%以上,各专业毕业设计应符合专业培养目标要求。三、对指导教师的要求 1、毕业设计(论文)实行指导教师负责制。指导教师原则上由讲师职称以上的教师担任,助教一般不单独指导毕业设计 (论文)。对确因师资困难,可成立毕业设计指导组共同完成毕业设计指导工作。 2、每名教师指导学生人数原则上不超过15名。设计(论文)题目做到1人1题,对一人不能完成的大型设计题目可多人分部分独立完成。 3、指导教师必须在毕业设计(论文)开始以前向学生下达书面毕业设计(论文)任务书。 4、指导教师要严格要求学生,认真指导毕业实习,明确实习、调研的内容和要求,并规定实习纪律,对分散实习的学生教师应填写并留存指导实习的电话记录等;定期指导学生毕业设计(论文),如实、认真填写毕业设计(论文)进度检查记录。5、指导教师要重视对学生独立分析问题、解决问题和创新能力的培养,要加强设计场所的纪律管理和对学生的考勤,随时掌握学生动向,要求学生保持设计场所的整洁、安静,做好教书育人工作。6、答辩结束后指导教师应及时将有关材料(纸质和电子)交资料室归档。 四、对学生的要求 1、学生在毕业实习、调研中应服从带队教师安排,自觉遵守纪律,注意安全。虚心向工人和技术人员学习,认真作好笔记、写好实习报告。毕业签辩时应将实习报告交答辩评审组审查,并作为毕业设计 (论文)评分的依据之一。 2、学生应完成毕业设计(论文)任务,做到设计合理,叙述简练,文字工整,绘图整洁、正确、规范,完成不少于 25000以上印刷符号的原版外文专业文献翻译,并将原文附于设计说明书。 3、设计类题目,每个学生应完成相当于34张0号图纸的设计图,每张图纸内容饱满,符合工程要求,必须手工绘制1张1号图幅的中等复杂程度的零件设计图,其余全部采用计算机绘图,说明书2000030000字;计算类题目,每个学生应完成相当于1.53张0号图纸的设计图,每张图纸内容饱满,符合工程要求,必须手工绘制1张1号图幅的中等复杂程度的零件设计图,其余全部采用计算机绘图;说明书1500025000字;特殊专业视具体情况确定。 4、学生在完成毕业设计(论文)后应做好整理、善后工作。一般应按毕业设计(论文)封面指导教师评语任务书目录具体内容封底的顺序装订成册,并与其它设计 (论文)资料一起装入毕业设计 (论文)资料袋中。 5、学生凡有以下情况之者,应取消答辩资格: (1)未完成指导教师规定的任务和要求; (2)说明书有严重错误或极其潦草; (3)图纸有严重错误或极其潦草; (4)设计中有三分之一时间不在设计场所,或擅自离校,旷课总计达七天以上; (5)查明有抄袭或代做者。 五、总结、评选、存档 1、在毕业设计(论文)答辩结束后1周内,各系(部、教研室)或答辩小组要认真作好本单位毕业设计(论文)工作总结(包括基本情况、课题完成情况、工作经验和教训等 ),工作总结应报院教务办公室存档。 2、毕业设计(论文)资料的保存。 毕业设计 (论文)资料(实习报告、开题报告、中期检查、设计说明书、设计图纸以及应有的电子文档)由指导教师负责整理,交院资料室保存,教师可随时借用。设计资料的电子文档以“指导教师姓名”命名总文件夹,包括以“每个学生姓名”命名的子文件夹,列出具体明细,条理要清晰,其工作可由指导教师负责,安排学生完成。 六、本规定自公布之日起执行。 附件: 1. 机械与动力工程学院本科生毕业设计(论文)撰写规范2. 机械与动力工程学院本科生毕业设计(论文)答辩程序和实施办法(暂行)3. 机械与动力工程学院本科生毕业设计(论文)流程(暂行)4. 机械与动力工程学院毕业设计(论文)进度检查记录5. 机械与动力工程学院本科毕业设计(论文)评分标准 二六年三月十日主题词:毕业设计 管理办法 机械与动力工程学院党政办公室 2006年3月10日印发附件1河南理工大学本科毕业设计(论文)开题报告题目名称学生姓名专业班级学号一、 选题的目的和意义:二、 国内外研究现状简述:。三、毕业设计(论文)所采用的研究方法和手段: 四、主要参考文献与资料获得情况:五、毕业设计(论文)进度安排(按周说明):六、指导教师审批意见(对选题的可行性、研究方法、进度安排作出评价,对是否开题作出决定): 指导教师: (签名)年 月 日 附件2河南理工大学本科毕业设计(论文)中期检查表指导教师: 职称: 所在院(系): 教研室(系、研究所): 题 目学生姓名专业班级 学号一、进度情况说明:二、阶段性成果:三、存在的主要问题及解决方法:四、指导教师对学生在毕业设计(论文)中的纪律及毕业设计(论文)任务的完成进展等方面的评语指导教师: (签名) 年 月 日附件3河南理工大学本科生毕业设计(论文)撰写规范一、毕业设计(论文)资料的组成、装订毕业设计(论文)资料应包括:毕业设计(论文)说明书、译文及原文影印件、工程图纸(按国家标准装订)、计算机编程软件(光盘或软盘)及使用说明书等。毕业设计(论文)说明书按统一标准装订,装订的顺序如下:毕业设计(论文)说明书封面毕业设计任务书毕业设计评阅人评语毕业设计评定书毕业设计答辩许可证毕业设计答辩委员会(小组)决议中文摘要外文摘要目录前言正文致谢参考文献附录封底。二、毕业设计报告(论文)的内容与要求一份完整的毕业设计(论文)应包括以下几方面。(一)论文题目论文题目应简短、明确、有概括性。通过题目使读者大致了解毕业设计(论文)的内容、专业的特点和科学的范畴。如果有些细节必须放进标题,为避免冗长,可以分成主标题和副标题,主标题写得简明,将细节放在副标题里。(二)论文摘要摘要应以浓缩的形式概括研究课题的内容、方法和观点,以及取得的成果和结论,应能反映整个内容的精华。中外文摘要以300500字为宜;撰写摘要时应注意以下几点:1用精炼、概括的语言来表达,每项内容不宜展开论证或说明;2要客观陈述,不宜加主观评价;3成果和结论性字句是摘要的重点,在文字论述上要多些,以加深读者的印象;4要独立成文,选词用语要避免与全文尤其是前言和结论部分雷同。(三)目录目录按三级标题编写(即:1.、1.1、1.1.1)要求标题层次清晰。目录中标题应与正文中标题一致。(四)前言应说明本课题的意义、目的、研究范围及要求达到的技术参数;简述本课题应解决的主要问题。(五)正文正文是作者对研究工作的详细表述。其内容包括:问题的提出,研究工作的基本前提、假设和条件;基本概念和理论基础;模型的建立,实验方案的拟定;基本概念和理论基础;设计计算的方法和内容;实验方法、内容及其分析;理论论证,理论在课题中的应用,课题得出的结果以及结果的讨论等。一般情况下,根据毕业设计(论文)课题的性质,正文可包含上述部分内容。撰写正文部分的具体要求如下:1理论分析部分应写明所作的假设及其合理性,所用的分析方法、计算方法、实验方法等,哪些是自己改进的,哪些是自己创造的,以便指导教师审查和纠正,篇幅不宜过多,应以简练的文字概略地表达。2对于用实验方法研究的课题,应具体说明实验用的装置、仪器的性能,并应对所用装置、仪器作出检验和标定。对实验的过程和操作方法,力求叙述简明扼要,对人所共知的内容或细节内容不必详述。对于经理论推导达到研究目的的课题,内容要精心组织,做到概念准确,判断推理符合客观事物的发展规律,符合人们对客观事物的认识习惯,换言之,要做到言之有序,言之有理,以论点为中心,组成完整而严谨的内容整体。3结果与讨论是全文的重要内容,在撰写时对必要而充分的数据、现象、认识等要作为分析的依据写进去。在对结果作定性和定量分析时,应说明数据的处理方法以及误差分析,说明现象出现的条件及其可证性,交代理论推导中认识的由来和发展,以便他人以此为依据进行实验验证。对结果进行分析后得出的结论,也应说明其适用的条件与范围。此外,适当运用图、表作为结果与分析,也是科技论文通用的一种表达方式,应精心制作、整洁美观。(六)结论结论包括对整个研究工作进行归纳和综合而得出的总结,还应包括所得结果与已有结果的比较和本课题尚存在的问题,以及进一步开展研究的见解与建议。结论集中反映作者的研究成果,表达作者对所研究的课题的见解,是全文的思想精髓,是文章价值的体现,结论要写得概括、简短。撰写时应注意以下几点。1结论要简洁、明确,措辞应严密,且容易被人领会;2结论应反映个人的研究工作,属于他人已有过的结论要少提;3要实事求是地介绍自已研究的成果,科学问题的探索是永无止境的,切忌言过其实,在无充分把握时应留有余地。(七)致谢致谢应以简短的文字对课题研究与论文撰写过程中曾直接给予帮助的人员(例如指导教师、答疑教师及其他人员)表示自已的谢意,这不仅是一种礼貌,也是对他人劳动的尊重,是毕业生未来科 技工作者应有的思想作风。(八)参考文献与附录参考文献是毕业设计(论文)不可缺少的组成部分,它反映毕业设计(论文)取材来源、材料的广博程度和材料的可靠程度。一份完整的参考文献也是向读者提供的一份有价值的信息资料。一般做毕业设计(论文)的参考文献不宜过多,但应列入主要的中外文献。对于一些不宜放入正文中、但作为毕业设计(论文)又不可或缺的组成部分,或有主要参考价值的内容,可编入毕业设计(论文)的附录中,例如,公式的推演、编写的算法语言程序等。如果毕业设计中引用的实例、数据资料,实验结果等符号较多时,为了节约篇幅,便于读者查阅,可以编写一个符号说明,注明符号代表的意义。附录的篇幅不宜太多,附录一般不要超过正文。附件1机械与动力工程学院本科生毕业设计(论文)撰写规范一、毕业设计(论文)资料的组成、装订毕业设计(论文)任务书资料应包括:评语、毕业设计报告(论文)、说明书;中外文摘要;目录、参考文献附录;译文及原文影印件;工程图纸(按国家标准装订)、计算机编程软件(软盘)使用说明书;正文、封面等。毕业设计(论文)按统一标准装订,装订的顺序如下:毕业设计(论文)封面毕业设计任务书毕业设计评阅人评语毕业设计评定书毕业设计答辩许可证毕业设计答辩委员会(小组)决议中文摘要外文摘要目录前言正文致谢参考文献资料附录译文及原文影印件封底。二、毕业设计报告(论文)的内容与要求一份完整的毕业设计报告(论文)应包括以下几方面。(一)论文题目论文题目应简短、明确、有概括性。通过题目使读者大致了解毕业设计(论文)的内容、专业的特点和科学的范畴。如果有些细节必须放进标题,为避免冗长,可以分成主标题和副标题,主标题写得简明,将细节放在副标题里。(二)论文摘要摘要应以浓缩的形式概括研究课题的内容、方法和观点,以及取得的成果和结论,应能反映整个内容的精华。中外文摘要以300500字为宜;撰写摘要时应注意以下几点:1用精炼、概括的语言来表达,每项内容不宜展开论证或说明;2要客观陈述,不宜加主观评价;3成果和结论性字句是摘要的重点,在文字论述上要多些,以加深读者的印象;4要独立成文,选词用语要避免与全文尤其是前言和结论部分雷同。(三)目录目录按三级标题编写(即:1.、1.1、1.1.1)要求标题层次清晰。目录中标题应与正文中标题一致。(四)绪论应说明本课题的意义、目的、研究范围及要求达到的技术参数;简述本课题应解决的主要问题。(五)正文正文是作者对研究工作的详细表述。其内容包括:问题的提出,研究工作的基本前提、假设和条件;基本概念和理论基础;模型的建立,实验方案的拟定;基本概念和理论基础;设计计算的方法和内容;实验方法、内容及其分析;理论论证,理论在课题中的应用,课题得出的结果,以及结果的讨论等。一般情况下,根据毕业设计(论文)课题的性质,正文可包含上述的部分内容。撰写正文部分的具体要求如下:1理论分析部分应写明所作的假设及其合理性,所用的分析方法、计算方法、实验方法等,那些是自己改进的,那些是自己创造的,以便指导教师审查和纠正,篇幅不宜过多,应以简练的文字概略地表达。2对于用实验方法研究的课题,应具体说明实验用的装置、仪器的性能,并应对所用装置、仪器作出检验和标定。对实验的过程和操作方法,力求叙述简明扼要,对人所共知的内容或细节内容不必详述。对于经理论推导达到研究目的的课题,内容要精心组织,做到概念准确,判断推理符合客观事物的发展规律,符合人们对客观事物的认识习惯,换言之,要做到言之有序,言之有理,以论点为中心,组成完整而严谨的内容整体。3结果与讨论是全文的重要内容,在撰写时对必要而充分的数据、现象、认识等要作为分析的依据写进去。在对结果作定性和定量分析时,应说明数据的处理方法以及误差分析,说明现象出现的条件及其可证性,交代理论推导中认识的由来和发展,以便他人以此为依据进行实验验证。对结果进行分析后得出的结论,也应说明其适用的条件与范围。此外,适当运用图、表作为结果与分析,也是科技论文通用的一种表达方式,应精心制作、整洁美观。(六)结论结论包括对整个研究工作进行归纳和综合而得出的总结,还应包括所得结果与已有结果的比较和本课题尚存在的问题,以及进一步开展研究的见解与建议。结论集中反映作者的研究成果,表达作者对所研究的课题的见解,是全文的思想精髓,是文章价值的体现,结论要写得概括、简短。撰写时应注意以下几点。1结论要简洁、明确,措辞应严密,且又容易被人领会; 2结论应反映个人的研究工作,属于他人已有过的结论要少提;3要实事求是地介绍自已研究的成果,科学问题的探索是永无止境的,切忌言过其实,在无充分把握时应留有余地。(七)致谢致谢应以简短的文字对课题研究与论文撰写过程中曾直接给予帮助的人员(例如指导教师、答疑教师及其他人员)表示自已的谢意,这不仅是一种礼貌,也是对他人劳动的尊重,是毕业生未来科技工作者应有的思想作风。(八)参考文献与附录参考文献是毕业设计(论文)不可缺少的组成部分,它反映毕业设计(论文)的取材来源、材料的广博程度和材料的可靠程度。一份完整的参考文献也是向读者提供的一份有价值的信息资料。一般做毕业设计(论文)的参考文献不宜过多,但应列入主要的中外文献。对于一些不宜放入正文中、但作为毕业设计(论文)又不可或缺的组成部分,或有主要参考价值的内容,可编入毕业设计(论文)的附录中,例如,公式的推演、编写的算法语言程序等。如果毕业设计中引用的实例、数据资料,实验结果等符号较多时,为了节约篇幅,便于读者查阅,可以编写一个符号说明,注明符号代表的意义。附录的篇幅不宜太多,附录一般不要超过正文。 三、毕业设计(论文)的书写格式(一)毕业设计(论文)一律采用国家文字改革委员会正式公布的简化汉字,论文提倡采用计算机排版、打印(用学校规定的稿纸B5复印纸)。论文要求语句通顺、论述严谨、程序和实验数据完整、齐全、规范、正确。论文采用河南理工大学本科生毕业设计(论文)统一封面。封页上的内容由本人用碳素墨水钢笔填写或打印; (二)毕业设计(论文)中标点符号应按新闻出版署公布的“标点符号用法”使用;(三)科学技术名词术语尽量采用全国自然科学名词审定委员会公布的规范词或国家标准、部标准中规定的名称,尚未统一规定或叫法有争议的名词术语,可采用惯用的名称;(四)使用外文缩写代替某一名词术语时,首次出现时应在括号内注明其含义,如CPU(Central Processing Unit)代替计算机中央处理器。外国人名一般采用英文原名,可不译成中文,英文人名按名前姓后的原则书写。一般很熟知的外国人名(如牛顿、爱因斯坦、达尔文、马克思等)可按通常标准译法写译名;(五)毕业设计(论文)中的量和单位必须采用中华人民共和国家标准,它是以国际单位制(SI)为基础的。非物理量的单位,如件、台、人、元等,可用汉字与符号构成组合形式的单位,例如件/台、元/km;(六)毕业设计(论文)中的数量、统计数据一律用阿拉伯数字,如5.25MeV等。在叙述不很大的数目时,一般不宜用阿拉伯数字; (七)毕业设计(论文)的全部标题层次应有条不紊,整齐清晰,相同的层次应采用统一的表示体例,正文中各级标题下的内容应同各自的标题对应,不应有与标题无关的内容。章节编号方法应采用分级阿拉伯数安编号方法,第一级为“1”、“2”、“3”、等,第二级为“2.1”、“2.2”、“2.3”等,第三级为“2.2.1”、“2.2.2”、“2.2.3”等,但分级阿拉伯数字的编号一般不超过四级,两级之间用下角圆点隔开,除第一级外,其余各级的末尾不加标点。各层标题均单独占行书写,第一级标题居中书写,第二级标题序数顶格书写,空一格接写标题,末尾不加标点,第三级和第四级标题均空两格书写序数,空一格写标题。第四级以下单独占行的标题须序采用A.B.C.和a.b.c.两层,标题均空两格书写序数,空一格写标题。正文中对总项包括的分项采用(1)、(2)、(3)的序号,对分项中的小项采用、的序号,数字加半括号或括号后,不再加其它标点;(八)毕业设计(论文)中有个别名词或情况需要解释时,可加注说明,注释可用页末注(将注文放在加注页稿纸的下端)或篇末注(将全部注文集中在文章末尾),而不用行中注(夹在正文中的注)。若在同一页中有两个以上的注时,按各注出现的先后,顺序编列注号,注释只限于写在注释符号出现的同页,不得隔页;(九)公式应另起一行写在稿纸中央,一行写不完的长公式,最好在等号处转行,如做不到这点,在数学符号(如“+”、“-”号)处转行,数学符号应写在转行后的行首。公式的编号用圆括号括起放在公式右边行末,在公式和编号之间不加虚线,公式可按全文统一编序号,公式序号必须连续,不得重复或跳缺。重复引用的公式不得另编新序号。公式中分数的横分线要写清楚,特别是连分数(即分子和分母也出现分数时)更要注意分线的长短,并将主要分线和等号对齐。在叙述中也可将分数的分子和分母平列在一行,用斜线分开表述;(十)每个表格应有自已的表题和表序,表题应写在表格上方正中,表序写在表题左方不加标点,空一格接写表题,表题末尾不加标点。全文的表格统一编序,也可以逐章编序,不管采用哪种方式,表序必须连续。表格允许下页接写,接写时表题省略,表头应重复书写,并在右上方写“续表”。此外,表格应写在离正文首次出现处的近处,不应过分超前或拖后;(十一)毕业设计(论文)的插图必须精心制作,线条要匀称,图面要整洁美观,插图应与正文呼应,不得与正文脱节。每幅插图应有图序和图题,全文插图可以统一编序,也可以逐章单独编序,不管采用哪种方式,图序必须连续,不得重复或跳缺。由若干分图组成的插图,分图用a,b,c标序,分图的图名以及图中各种代号的意义,以图注形式写在图题下方,先写分图名,另起行后写代号的意义。图应在描图纸或白纸上用墨线绘成,或用计算机绘图,电气图或机械图应符合相应的国家标准的要求。(十一)字体字号要求字体 :宋体 一级标题:三号 二级标题:四号三级标题:小四 正 文:五号(十二)参考文献格式参考文献按照文后参考文献著录规则(GB771487)的规定书写,并按顺序编码制,即按中文引用的顺序将参考文献附于文末。多位作者,姓名写到第三位,余者写“,等”或“,et al”。几种主要参考文献著录表的格式为:连续出版物:序号 作者题目。刊名,年,卷号(期号):起止页码专(译)著:序号 作者书名(,译者)出版地:出版者,出版年起止页码论文集:序号 作者. 题目. 见(In):编者(eds). 文集名.出版地:出版者,出版年.起止页码学位论文:序号 姓名题目:XX学位论文授予单位所在地:授予单位,授予年技术标准:序号 发布单位技术标准代号技术标准名称出版地:出版者,出版日期。附件2机械与动力工程学院本科生毕业设计(论文)答辩程序和实施办法(暂行)一、答辩程序1答辩资格审查凡本科生毕业设计(论文)按计划完成者,其论文经院(系)形式审查通过,方获得参加答辩资格。2.毕业设计(论文)答辩毕业设计(论文)形式审查通过后,由专业答辩小组主持答辩并以公开方式进行。答辩前,答辩小组每个成员都必须详细审阅每位学生毕业设计(论文)报告,了解设计(论文)的质量和水平,并准备答辩时应向学生提出的问题,为答辩作好准备。答辩中,学生须报告自己毕业设计(论文)的主要内容(约15分钟,但不少于10分钟),并回答答辩小组成员的提问。每个学生答辩时间不少于30分钟。答辩过程中,应做好记录供评定成绩时参考。3.成绩评定答辩前每个学生都要将自己的毕业设计(论文)在指定的时间内交给指导教师,由指导教师审阅,写出评语并预评分。答辩工作结束后,答辩小组应举行专门会议按学校和学院统一的评分标准和评分办法,在参考指导教师预评结果的基础上,评定每个学生的成绩。系(部)对专业答辩小组提出的优秀和不及格的毕业设计(论文),要组织系(部)级答辩,最终确定成绩,并向学生公布。二、实施办法1各系(部、教研室)毕业设计(论文)答辩工作,在主管院长统一领导下进行。2学院实行优秀申报制度,申报优秀毕业设计的学生必须参加大组答辩;其他学生可根据学生人数的多少,按专业成立若干个答辩小组。每一答辩小组,可设秘书1人(负责答辩时记录),成员57人。答辩小组名单在答辩前5天报送教学秘书备案,由教学院长统一协调。3答辩小组的职责是:安排答辩程序,主持答辩过程,按照毕业设计评分标准评定学生成绩并写出评语。4答辩工作结束后,答辩小组应向教学院长作出书面报告。附件3机械与动力工程学院本科生毕业设计(论文)流程(暂行)序号内容负责人时间说明1毕业设计题目申报教学院长、教学秘书前一学期第16-17周指导教师在前一学期第16-18周将设计题目和拟指导人数报到教学秘书处,附电子文档,教学秘书将全院指导教师设计题目汇总好,分专业列出2师生双向选择教学院长、教学秘书前一学期第18周分专业将设计题目发于学生处,由学生自愿选择。班主任应做适当辅导工作3安排毕业实习系、教研室主任第1周各系、教研室统一领取实习经费,协调各指导教师联系毕业实习地点,实习地点要符合设计题目要求,报实习安排表4毕业实习指导教师第57周由指导教师负责安排具体实习事宜5开题报告指导教师第68周按照学校格式填写开题报告,经指导教师审查合格后方可进行设计,开题报告由指导教师统一保存至答辩前;抽查6进度检查记录指导教师第918周认真填写机械与动力工程学院毕业设计(论文)进度检查记录7中期检查指导教师第1112周指导教师认真检查学生设计进度和质量,按照学校要求填写中期检查表,由指导教师统一保存至答辩前;抽查8期中教学检查教学院长、系、教研室主任第1011周检查全院毕业实习、设计进行情况,分别开指导教师、学生代表座谈会,及时发现实际存在问题,并协商解决,教学秘书提出书面总结9毕业答辩小组安排教学院长、教学秘书第14周制定机械学院答辩委员会名单。按学生专业及答辩程序要求划分答辩小组,评优学生必须参加大组答辩10毕业设计审查答辩委员会、答辩小组第1617周对学生毕业设计的相关资料(设计说明书、图纸、开题报告、中期检查、文献翻译、毕业实习报告)以及论文格式等进行审查,合格者可以进行答辩,不合格者进行修改合格后方能答辩,修改后仍不合格者取消答辩资格11毕业设计答辩答辩委员会、答辩小组第1718周按照要求,本着“公平、公正”原则,进行毕业答辩,认真做好记录,答辩后上交答辩记录12毕业设计成绩审定答辩委员会、答辩小组第1718周答辩委员会、答辩小组确定学生答辩成绩,汇总到专业教研室主任处,在教务管理系统中录入成绩,一式四份打印后交教务科、院教学秘书、教学干事,教研室存留一份13修改、整理毕业设计资料指导教师第1819周6月25日前根据答辩过程情况,修改答辩过程中提出的问题,整理毕业答辩资料(签字要完全),按要求装入档案袋14毕业设计存档资料管理员、指导教师第19周由指导教师将毕业设计资料(包括电子文档)按规定存到资料室,并办理相关交接手续15毕业设计总结答辩委员会、答辩小组第20周答辩结束后,答辩小组提交书面总结,经院答辩委员会主席、教学院长审阅后,由教学秘书做书面总结报告,书面总结由教学秘书归档附件4机械与动力工程学院毕业设计(论文)进度检查记录 题目学生姓名学号专业班级指导教师姓名指导教师职称日 期指 导 记 录可另附页指导教师:(签字) 附件5机械与动力工程学院本科毕业设计(论文)评分标准项目分值优秀(100x90)良好(90x80)中等(80x70)及格(70x60)不及格(x60)评分参考标准参考标准参考标准参考标准参考标准调研论证10能独立查阅文献以及从事其它形式的调研,能较好地理解课题任务并提出实施方案,有分析整理各类信息、从中获取新知识的能力除全部阅读教师指定的参考资料、文献外,还能阅读一些自选资料,能较好地分析整理各类信息,并提出较合理的实施方案能阅读教师指定的参考资料、文献,能分析整理各类信息能力,有实施方案能阅读教师指定的参考资料,有实施方案未完成教师指定的参考资料及文献的阅读,无信息分析整理,实施方案不合理外文翻译5按要求按时完成外文翻译,译文准确质量好按要求按时完成外文翻译,译文质量较好按要求按时完成外文翻译,译文质量尚可按要求按时完成外文翻译外文翻译达不到要求技术水平与实际能力20设计合理、理论分析与计算正确,实验数据准备可靠,有较强的实际动手能力、经济分析能力和计算机应用能力设计比较合理、理论分析与计算正确,实验数据比较准确,有一定的实际动手能力、经济分析能力和计算机应用能力设计比较合理,理论分析与计算基本正确,实验数据基本准确,实际动手能力尚可,论文中涉及了经济问题设计基本合理,理论分析与计算无大错设计不合理,理论分析与计算有原则错误,实验数据不可靠,实际动手能力差研究成果、基础理论与专业知识20对研究的问题能较深刻分析或有独到之处,成果突出,反映出作者很好地掌握了有关基础理论与专业知识对研究的问题能正确分析或有新见解,成果比较突出,反映出作者较好地掌握了有关基础理论与专业知识对研究的问题能提出自己的见解,成果有一定意义,反映出作者基本掌握了有关基础理论与专业知识对某些问题提出个人见解,并得出研究结果,作者对基础理论和专业知识基本掌握缺乏研究能力,未取得任何成果,反映出作者基础理论和专业知识很不扎实创新10有重大改进或独特见解,有一定实用价值有较大改进或新颖的见解,实用性尚可有一定改进或新的见解有一定见解观念陈旧论文(说明书)撰写质量15论文结构严谨,逻辑性强,论述层次清晰,语言准确,文字流畅,完全符合规范化要求,用计算机打印成文论文结构合理,符合逻辑,文章层次分明,语言准确,文字流畅,达到规范化要求,用计算机打印成文论文结构基本合理,层次较为分明,文理通顺,基本达到规范化要求论文结构基本合理,论证基本清楚,文字尚通顺,勉强达到规范化要求内容空泛,结构混乱,文字表达不清,错别字较多,达不到规范化要求答辩情况15能简明扼要、重点突出地阐述论文的主要内容,能准确流利地回答各种问题能比较流利、清晰地阐述论文的主要内容,能较恰当地回答与论文有关的问题基本能叙述出论文的主要内容,对提出的主要问题一般能回答,无原则错误能阐明自己的基本观点,答辩错误经提示后能作补充或进行纠正不能阐明自己的基本观点,主要问题答不出或有原则错误,经提示后仍不能回答有关问题学习态度5学习态度认真,科学作风严谨,严格保证设计时间并按任务书中规定的进度开展各项工作学习态度比较认真,科学作风良好,能按期圆满完成任务书规定的任务学习态度尚好,遵守组织纪律,基本保证设计时间,按期完成各项工作学习态度尚可,在指导教师的帮助下能按期完成任务学习马虎,纪律涣散,工作作风不严谨,不能保证设计时间和进度总成绩100机械与动力工程学院毕业设计答辩评分表序号学生姓名调研论证(10)外文翻译(5)技术水平与实际能力(20)研究成果、基础理论与专业知识(20)创新(10)论文(说明书)撰写质量(15)答辩情况(15)学习态度(5)总成绩(100)答辩委员:(签字)Journal of Materials Processing Technology 83 (1998) 151158Machining of Al/SiC particulate metal-matrix compositesPart I: Tool performanceM. El-Gallaba, M. Skladb,*aPratt and Whitney Canada, Mississauga, Ontario, L5T1J3, CanadabDepartment of Mechanical Engineering, McMaster Uni6ersity, Hamilton, Ontario, L8S4L7, CanadaReceived 20 March 1997AbstractDespite the superior mechanical and thermal properties of particulate metal-matrix composites, their poor machinability hasbeen the main deterrent to their substitution for metal parts. The hard abrasive reinforcement phase causes rapid tool wear duringmachining and, consequently, high machining costs. A series of dry high-speed turning tests were performed to select the optimumtool material, tool geometry and cutting parameters for the turning of 20%SiC/Al metal-matrix composites. The results indicatethat polycrystalline diamond tools (PCD) provide satisfactory tool life compared to alumina and coated-carbide tools, where thelatter tools suffered from excessive edge chipping and crater wear during the machining of the metal-matrix composite understudy. Furthermore, the cost of PCD tools could be justified by using dry cutting at feed rates as high as 0.45 mm rev1, cuttingspeeds of 894 m min1and a depth of cut of 1.5 mm. With these cutting parameters, the relatively small built-up edge formedon the tool protects it from further wear by abrasion and micro-cutting. Polycrystalline tools with zero rake angle and large toolnose radii are recommended for the roughing operations. 1998 Elsevier Science S.A. All rights reserved.Keywords:Metal-matrix composites; Tool wear1. IntroductionMetal-matrix composites (MMCs) form one group ofthe new engineered materials that have received consid-erable research since the trials by Toyota in the early1980s 1. The most popular reinforcements are siliconcarbide and alumina. Aluminium, titanium and magne-sium alloys are commonly used as the matrix phase.The density of most MMCs is approximately one thirdthat of steel, resulting in high specific strength andstiffness 2. Due to these potentially attractive proper-ties coupled with the inability to operate at high tem-peratures, MMCs compete with super-alloys, ceramics,plastics and re-designed steel parts in several aerospaceand automotive applications. The latter materials, how-ever, may not have much further capacity for theinevitable future increases in service loads 3.Particulate metal-matrix composites (PMMCs) are ofparticular interest, since they exhibit higher ductilityand lower anisotropy than fiber reinforced MMCs 2.Moreover, PMMCs offer superior wear resistance 3.WhilemanyengineeringcomponentsmadefromPMMCs are produced by the near net shape formingand casting processes, they frequently require machin-ing to achieve the desired dimensions and surface finish.The machining of PMMCs presents a significant chal-lenge, since a number of reinforcement materials aresignificantly harder than the commonly used high-speedsteel (HSS) and carbide tools 4. The reinforcementphase causes rapid abrasive tool wear and therefore thewidespread usage of PMMCs is significantly impededby their poor machinability and high machining costs.2. Literature reviewFrom the available literature on PMMCs, it is clear* Corresponding author. Fax: +1 905 5727944; e-mail: mech-macmcmaster.ca0924-0136/98/$19.00 1998 Elsevier Science S.A. All rights reserved.PIIS0924-0136(98)00054-5M. El-Gallab, M. Sklad/Journal of Materials Processing Technology83 (1998) 151158152Table 1Typical physical properties of Duralcan F3S.20S 20PropertyDensity (g cm3)2.77Thermal conductivity (cal cm1s1K1) at 22C0.47Specific heat (cal g1K)0.218100C0.239200C0.259300CAverage coefficient of thermal expansion17.550100C50300C21.121.450500CUltimate strength (MPa)262Yield strength (MPa)21.41.9Elongation (%)98.6Elastic modulus (GPa)6791.5Rockwell hardness (B)Table 2Tool geometryToolGeometryPCD (tipped-80rhomboid)Rake angle, a: 5, 0, 5Clearance angle: 7Approach angle: 5Tool nose radius (mm), r: 0.8, 1.6TiN coated carbideRake angle, a: 0(triangular)Clearance angle: 7Approach angle: 5Tool nose radius (mm), r: 1.6Rake angle, a: 0Al2O3/TiC ceramic(triangular)Clearance angle: 7Approach angle: 5Tool nose radius (mm), r: 1.6crystalline diamond (PCD) tools are the only tool mate-rial that is capable of providing a useful tool life duringthe machining of SiC/Al PMMCs. PCD is harder thanAl2O3and SiC and does not have a chemical tendencyto react with the workpiece material. Tomac et al. 5compared the performance of chemical vapor deposi-tion (CVD) inserts to that of TiN, Ti(CN) and Al2O3coated tools. CVD tools offered better overall perfor-mance than that of the other tools. Lane et al. 18studied the performance of different CVD tools withthin and thick films. According to their observations,CVD tools with thin films failed catastrophically duringthe end milling of 20%SiC/Al PMMC. This tool failurewas attributed to coating spalling and consequent dam-age to the relatively soft carbide substrate. Further-more, PCD tools with a grain size of 25 mm betterwithstand abrasion wear by micro-cutting than toolswith a grain size of 10 mm 8,14. Further increases inPCD grain size do not benefit the tool life, but rathercause significant deterioration in the surface finish. Thisthat the morphology, distribution and volume fractionof the reinforcement phase, as well as the matrix prop-erties, are all factors that affect the overall cuttingprocess 2,4, but as yet relatively few works related tothe optimization of the productivity process have beenpulished. For example, Monaghan 2 studied the wearmechanism of carbide tools during the machining of25% SiC/Al PMMC at speeds below 20 m min1.Tomac et al. 5 developed a tool life relationship forcarbide tools during the machining of SiC/Al PMMCsat speeds lower than 100 m min1. However, theauthors of Ref. 5 recommended further research onthe built-up edge phenomenon that is observed in alltools during the machining of SiC/Al PMMCs. OReillyet al. 6 ranked various tool materials with respect totool wear, however, their cutting parameters did notexceed 125 m min1and 1.0 mm depth of cut, whichwas achieved using cubic boron nitride tools. Similartest results were reported by Brun et al. 7 who relatedthe tool wear rate, mainly due to abrasion, to the toolhardness. Winert 8 attributed the wear of the carbidetools to abrading Al2O3particles that form on thesurface and rub the tool in the direction of the chipflow. However, pulled SiC particles could also lead tothe same effect, SiC particles also being harder than theWC. Tomac et al. 5 suggested that coatings with lesshardness than that of Al2O3and SiC offer little to noadvantage during the machining of SiC/Al PMMCs,Brun et al. 7 suggested using lower cutting speeds toreduce the cutting temperature, which accelerate diffu-sion and adhesion wear and thermally weaken the tool.Since aluminium tends to seize on the tool face andsince grain boundaries are the sites of seizure, theauthors recommended using cemented carbide toolswith a large grain size.Several researchers 725 have indicated that poly-Fig. 1. SEM figure showing wear on Al2O3tool (6=488 m min1,f=0.2 mm rev1, doc=0.5 mm, r=1.6 mm, a=0).M. El-Gallab, M. Sklad/Journal of Materials Processing Technology83 (1998) 151158153Table 3Effect of tool material on cutting forces and temperatures (r=1.6mm; a=0)Measured cut-Tool materialMeasured cuttingtemperature (C)ting force (N)PCD (6=894 m min1;97.00440f=0.45 mm rev1;doc=2.5 mm)98.10PCD (6=670 m min1;410f=0.25 mm rev1;doc=1.5 mm)520Al2O3(6=248 m min1;183.85f=0.2 mm rev1;doc=0.5 mm)143.52500TiN (6=248 m min1;f=0.2 mm rev1;doc=0.5 mm)Fig. 3. Effect of depth of cut on the cutting forces (PCD tool: r=1.6mm, a=0; square points: 6=894 m min1, doc=1.5 mm; roundpoints: 6=894 m min1, doc=2.5 mm).of cut that are as aggressive as possible during theroughing operations. Finally, with regard to the coolantapplication, researchers at Duralcan USA 1123, rec-ommend investigating the possibility of dry-rough ma-chining in order to take advantage of the protectivebuilt-up edge phenomenon.In summary, the literature review carried out showedthat the effect of more aggressive cutting parameters(speed, feed and depth of cut) still needs further re-search in order to improve the economics of the cuttingprocess. Also, several important parameters have beenoverlooked by previous researchers, among which arethe tool geometry and coolant application.3. Test material and cutting tools3.1.Workpiece materialThe machining investigations were carried out usingDuralcan F3S.20S Al/SiC metal-matrix composite. TheSiC particles had an average diameter of 12 mm. Table1 shows some of the physical and mechanical propertiesof A356-20%SiC PMMC. Prior to carrying out thecutting experiments, the test material was fully heat-treated to the T71 condition. The test material was inthe form of bars of 177.8 mm diameter and 305 mmlength.3.2.Cutting toolsVarious tool materials (coated carbide, Al2O3/TiCand PCD) and geometries were employed in the study.Oblique turning tests were carried out and differentcutting parameters were employed for each tool mate-rial. However, for the purpose of comparing tool wear,all cutting tests were carried out at a fixed volume ofmetal removed (300 mm3). Table 2 summarizes the tooldata.is because PCD grains with size 25 mm are easilypulled out of the cutting edge.Regarding the effect of the cutting parameters on thetool life, Lane et al. 1115,1719 attributed the in-crease in the wear of PCD tools (by abrasion) toincrease in kinetic energy gained by abrading SiC parti-cles. On the other hand, Brun et al. 7 attributed theincrease in tool wear in the thermal degradation of thetool material. Tool wear was found to be inverselyproportional to the feed rate 9. Tomac et al. 5attributed the increase in tool life at higher feed rates tothe thermal softening of the composite. The authorssuggest that the workpiece material becomes softer andthe SiC particles become pressed into the workpiece,causing less abrasion on the tool itself. However, Finnet al. 24 and Morin et al. 25 attributed the reductionin tool wear with greater feed rates to the reducedcontact between the cutting edge and the abrasive SiCparticles. Despite the controversy in explaining themechanism behind the tool wear at different feed rates,all researchers recommend using feed rates and depthsFig. 2. Effect of cutting speed on the cutting forces (PCD tool: r=1.6mm, a=0; square points: 6=670 m min1, doc=1.5 mm; roundpoints: 6=894 m min1, doc=1.5 mm).M. El-Gallab, M. Sklad/Journal of Materials Processing Technology83 (1998) 151158154Dry turning tests were carried out on a 10 HPStandard Modern NC lathe. The cutting force compo-nents (Fx, Fy, Fz) and tool wear were measured contin-uously for each combination of cutting parameters. Thetool forces were measured using a Kistler 3-componentdynamometer and the cutting conditions were selectedcarefully for each tool material. In some of the cuttingtests, the tool temperature was measured using K-typethermocouples that were glued onto the tool rake face,1 mm away from the cutting edge. The reliability of themeasurement techniques was checked constantly byrepeating the experiments and the results of each set ofexperiments were accepted if they exhibited a varianceof less than 5%. At the end of each cutting test, the toolwear was examined using a scanning electron micro-scope and the X-ray dispersion technique. The toolFig. 5. (a) Built-up edge on PCD tools (6=670 m min1, f=0.45mm rev1; doc=2.5 mm, r=1.6 mm); (b) as for Fig. 5(a), but for6=894 m min1.Fig. 4. (a) Built-up edge on PCD tools (6=670 m min1, f=0.25mm rev1, doc=2.5 mm, r=1.6 mm, a=0); (b) X-ray dispersionof built-up edge shown in Fig. 4(a).flank wear (VB) was measured using a toolmakersmicroscope.4. Results and discussion4.1.Effect of tool materialA series of preliminary tests was conducted to assesthe effect of tool material on the tool wear, cuttingforces and cutting temperature during the rough turn-ing of 20%SiC/Al PMMC. Fig. 1 shows that Al2O3/TiCtools suffered excessive wear in the form of edge chip-ping. Al2O3particles are pulled out by the abradingworkpiece particles, which have a greater Vickers hard-ness number (VHN) than the Al2O3particles (VHN forAl2O3TiC=2500 kgfmm2; VHN for SiC=3000 kgfmm2). Crater wear was also observed, which is due tothe widening of grooves that were caused by abrasion.Due to severe edge chipping, the cutting forces for theM. El-Gallab, M. Sklad/Journal of Materials Processing Technology83 (1998) 151158155Al2O3/TiC tool were much higher than those experi-enced by TiN coated tools (Table 3). The TiN coatingprovided some protection against the abrasive effects ofthe SiC particles. The superior performance of poly-crystalline diamond tools, compared to both Al2O3/TiCand TiN coated carbide tools, is attributed to their highabrasion resistance and high thermal conductivity,which led to lower cutting temperatures, as shown inTable 3. Therefore, all machinability studies carried outthereafter were concerned with the optimization of thecutting process using PCD tools.4.2.Effect of cutting parametersFigs. 2 and 3 show that as the cutting speed and/orthe depth of cut increase, the cutting forces decrease.This could be attributed to thermal softening of theworkpiece material. Another possible reason is due tothe changes introduced into the tool geometry upon theformation of built-up edge. Fig. 4(b) shows the X-raydispersion of the built-up material shown in Fig. 4(a).Fig. 7. (a) SEM image illustrating the wear on the PCD tool rake faceafter dissolving the BUE with NaOH (6=670 m min1, f=0.15 mmrev1, doc=1.5 mm, r=1.6 mm, a=0); (b) higher magnification ofrake face of the tool shown in Fig. 7(a).Fig. 6. (a) Built-up edge on PCD tools (6=670 m min1, f=0.35mm rev1, doc=1.5 mm, r=1.6 mm, a=0); (b) as for Fig. 6(a),but for doc=2.5 mm.Built-up edge was observed in all tools under all cuttingconditions. This is because particulate SiC/Al MMCshave all of the characteristics of materials that formFig. 8. Effect of cutting speed on the tool flank wear (PCD tool:r=1.6 mm, a=0; square points: 6=670 m min1, doc=1.5 mm;round points: 6=894 m min1, doc=1.5 mm).M. El-Gallab, M. Sklad/Journal of Materials Processing Technology83 (1998) 151158156Fig. 9. Effect of depth of cut on the tool flank wear (PCD tool:r=1.6 mm, a=0, 6=894 m min1; square points: doc=1.5 mm;round points: doc=2.5 mm).illustrate this point, in the case of a greater depth of cuta larger surface area of the tool flank face is exposed toabrasion.Increasing the feed rate had a beneficial effect. Asshown in Figs. 8 and 9, as the feed rate increases, thetool wear decreases. In the case of higher feed rates, fora fixed volume of metal removal, the tool surfaces willhave less contact with the abrasive PMMC. AnotherFig. 10. (a) Effect of PCD tool rake angle on tool flank wear (6=894m min1, doc=2.5 mm, r=1.6 mm; square points: 0; round points:5; star points, +5); (b) effect of PCD tool rake angle on thecutting forces (6=894 m min1, doc=2.5 mm, r=1.6 mm; squarepoints: 0; round points: 5; star points, +5); (c) SEM imageillustrating the PCD tool wear by pitting (6=670 m min1, doc=1.5mm, f=0.25 mm rev1, r=1.6 mm, a= +5).BUE (i.e. strain-hardened two-phase material underhigh temperature and pressure).At high cutting speeds (6=894 m min1(Fig. 5(b),a smaller BUE is formed, compared to the BUE formedat 6=670 m min1(Fig. 5(a); the height of the BUEwas measured perpendicular to the rake face) In con-trast, by increasing the depth of cut from 1.5 to 2.4mm, a large BUE is formed (Fig. 6(a,b), which couldbreak off the tool causing tool chipping and consequentadverse effects on the workpiece surface roughness anddimensional accuracy.Topographies of the tool indicate that the main wearmechanism of PCD is abrasion (manifested as groovesparallel to the chip flow direction). These grooves couldbe attributed to three factors. The first is that Al2O3isformed at the tool edge, which is hard enough toproduce grooving wear in the PCD. The second expla-nation for the PCD grooving is aluminium seizure andthe pull-out process of the PCD grain, as shown in Fig.7(a,b). The third possible reason behind PCD groovingis that SiC particles abrade the tools. Thus, PCD toolswith PCD grains larger than the grain size of the SiCparticles could better withstand the abrasion and mi-cro-cutting by the SiC particles. However, one shouldnote that as the size of the PCD grains increases, thefracture properties of the PCD tool deteriorates, due toan increased number of flaws in the material.The grooves that were formed on the tool face werefilled with the workpiece material. This adhering layersomewhat protected the tools rake face against furtherabrasion. Nonetheless, the tool flank face continued tobe subjected to abrasion. Hence, flank wear (Vb) wastaken as the tool life criterion with Vb1im=0.18 mm.Fig. 8 shows that as the cutting speed increases, theflank wear increases. This could be attributed to theincrease in the kinetic energy of the abrading particles,as previously hypothesized by Lane 17.Increasing the depth of cut leads to an increase in theflank wear (Fig. 9). This is attributed to enhancedabrasion by micro-cutting at the tool flank face. ToM. El-Gallab, M. Sklad/Journal of Materials Processing Technology83 (1998) 151158157Fig. 11. (a) SEM image illustrating the PCD tool wear by chipping(6=894 m min1, doc=1.5 mm, f=0.35 mm rev1, r=0.8 mm,a=0); (b) effect of tool nose radius on the tool flank wear (6=894min, doc=2.5 mm, a=0; tool FW: square points, r=1.6 mm;round pitch points, r=0.8 mm).wear in the case of negative rake angle, is the greatercutting forces encountered with such a rake angle (Fig.10(b). Moreover, the chips produced became caughtbetween the tool and the workpiece, causing damage tothe tool surface. Tools with positive rake angle showedirregular flank wear and excessive pitting in the cuttingedge zone, as shown in Fig. 10(c).The tool nose radius plays a key role in determiningthe wear mode of the tool. As the tool nose radius wasdecreased from 1.6 to 0.8 mm, the tool was found tosuffer from excessive chipping and crater wear, asshown in Fig. 11(a). This tool chipping leads to anincrease in cutting forces and flank wear, as shown inFig. 11(b). Tools with small nose radii are thus recom-mended for finishing operations where light cuttingparameters are used. Small nose radii are also expectedto yield better geometrical accuracy.5. ConclusionThe results of the machinability studies carried outon 20%SiC/Al particulate metal-matrix composites in-dicated the following.(1) The main tool wear mechanism is abrasion andmicro-cutting of tool material grains, manifested asgrooves on the tool face parallel to the chip flowdirection. All of the tools tested also suffered fromflank wear due to abrasion. There was no evidence ofchemical wear (e.g. by diffusion).(2) PCD tools sustained the least tool wear com-pared to TiN coated carbide tools and Al2O3/TiC tools.This is undoubtedly due to PCDs superior hardnessand wear resistance, as well as low coefficient of fric-tion, together with high thermal conductivity. This ledto lower cutting temperatures when PCD tools wereemployed. On the other hand, the TiN coated carbidetools and Al2O3/TiC tools suffered from excessivecrater wear and edge chipping.(3) The grooves formed on the rake face of PCDtools were filled with smeared workpiece material. Thisform of built-up edge is beneficial, since it protects thetool rake from further abrasion.(4) The cutting parameters play a key role in deter-mining the amount of tool flank wear, as well as thesize of the built-up edge. Tool wear is minimized byincreasing the feed rate, which leads to a reduction incontact between the tool and the abrading SiCp. Al-though increasing the cutting speed is expected to accel-erate the flank abrasion wear dramatically, the resultsindicated that the increase in wear is minimal. Highercutting speeds were associated with the increase in thecutting temperatures, which led to the formation of aprotective sticking thin layer of workpiece material onthe tool. This form of protective built-up edge wasprevented from growing in size by the increase speed ofadvantage gained by increasing the feed rate is thechange in chip form. At low feed rates, the chipsformed were continuous, also being difficult and haz-ardous to handle. At high feed rates and high depths ofcut ( f0.35, doc2.0 mm), the chips formed werediscontinuous. Despite the fact that in all experimentswith PCD tools high feed rates resulted in lower toolwear, a conclusive decision about the optimum cuttingparameters should take into consideration the effect ofthe cutting parameters on the surface integrity andsub-surface damage produced in the workpiece. Com-prehensive analysis of the surface integrity and chipmorphology will be presented in the Part II of thisresearch study.4.3.Effect of tool geometryThe tool rake angle had a profound effect on thewear of PCD tools. Three different rake angles wereexamined. As can be seen from Fig. 10(a), tools with 0rake angle out-performed positive and negative rakeangle tools. A possible reason for the increased flankM. El-Gallab, M. Sklad/Journal of Materials Processing Technology83 (1998) 151158158rubbing. Within the tested range of cutting parameters,the speed of 894 m min1, f=0.45 mm rev1anddepth of cut=1.5 mm resulted in the smallest toolwear. These cutting parameters enhance the productiv-ity rates upon using
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