【单选题】【消耗次数:1】
粗车碳钢工件时,刀具的磨损部位主要发生在()
前刀面
后刀面
前、后刀面
空气介质
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相关题目
【单选题】 前刀面与主后刀面的交线,它承担主要切削工作。是指( )
①  主后刀面Aa
②  前刀面Ay
③  主切削刃S
【单选题】 切削钢料时,常在主切刃靠近工件待加工表面处和副切削刃靠近刀尖处的后刀面上,磨出较深的沟纹,这种磨损称为( )
①  后刀面磨损
②  边界磨损
③  前刀面磨损
【单选题】 刀具后角的正负规定:后刀面与基面夹角小于 90o 时,后角为( )。
① 
② 
③  0
④  任意角
【判断题】 铣刀后刀面与工件已加工表面的挤压、摩擦小,刀刃磨损慢,工件加工表面质量较好,但工件表层的硬皮和杂质对刀具磨损影响较大,该说法( )
①  正确
②  错误
【单选题】 前刀面上出现积屑瘤对()有利。
①  粗加工
②  半精加工
③  光整加工
④  精加工
【单选题】 ( )是指在切削塑性材料时,由于切屑与前刀面之间的压力很大,再加上几百摄氏度的高温,使切屑底部与前刀面发生黏结。
①  冷焊
②  黏结
③  滑动
【单选题】 ( )的特点是在极短的时间内,后刀面磨损VB增加很快。
①  正常磨损阶段
②  急剧磨损阶段
③  初期磨损阶段
【判断题】 切削塑性材料时,切屑与前刀面的摩擦主要是普通摩擦。()
①  正确
②  错误
【判断题】 刀尖的圆弧半径和后刀面磨损量增大,将使冷作硬化层深度增大。
①  正确
②  错误
【单选题】 ( )是工件被切削层在刀具切削刃和前刀面的挤压作用下而产生以滑移为主的塑性变形过程。
①  金属切削
②  数控切削
③  机械切削
随机题目
【单选题】 What are language contents?
①  Structures, vocabulary, functions and topics
②  Pictures, vocabulary, communication and topics
③  PPT, structures, aims and summary
④  Structures, aims, functions and topics.
【单选题】 Which part is to be finished after a lesson in a lesson plan?
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【单选题】 What are the principles for good lesson planning?
①  Aim, variety, flexibility, learnability and linkage
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③  Aim, micro-planning, macro-planning and flexibility
④  Aim, micro-planning, macro-planning and variety.
【单选题】 What is the function of optional activities?
①  Backups in case the lesson goes too fast and there are a few minutes left
②  Prepared for good students
③  Prepared for bad students
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【单选题】 What are very commonly used teaching procedures and stages?
①  Presentation, practice and production
②  Pre-reading, while-reading and post-reading
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【单选题】 What are the guidelines for writing teaching aims in a lesson plan?
①  Clear, brief
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③  Specific, teacher-oriented
④  Both A and B.
【单选题】 What is discourse competence concerned with?
①  Appropriate use of the language in social context
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③  Strategies one employs when there is communication breakdown due to lack of resources
④  Knowledge of language itself, its form and meaning.
【单选题】 What is strategic competence concerned with?
①  Appropriate use of the language in social context
②  Ability to create coherent written text or conversation and the ability to understand them
③  Strategies one employs when there is communication breakdown due to lack of resources
④  Knowledge of language itself, its form and meaning.
【单选题】 What are the five components of communicative competence?
①  Linguistic competence, pragmatic competence, discourse competence, strategic competence and fluency
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③  grammar competence, pragmatic competence, discourse competence, strategic competence and fluency
④  grammar competence, pragmatic competence, discourse competence, strategic competence and accuracy.
【单选题】 What are the principles of communicative language teaching?
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②  Communication principle, accuracy principle and meaningful principle
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④  Communication principle, task principle and purpose principle.