资源描述：
《工程材料及机械制造基础复习(工程材料)g》由会员上传分享，免费在线阅读，更多相关内容在应用文档-天天文库。
1、工程材料及机械制造基础复习（Ⅰ）——工程材料工程材料1．1材料的力学性能1．2．1金属的晶体结构(1)基本概念①晶体与非晶体：两者的主要区别是：a．晶体中原子(或分子)按一定的几何规律作周期的重复排列；b．晶体具有固定的熔点；c．晶体具有各向异性。②晶格；为了便于表明晶体内部的原子排列规律，把每个原子看成一个点，点与点之间用直线连接起来而形成的空间格子。③晶胞：能完全反映晶格原子排列特征的最小几何单元。④晶格常数；晶胞的棱边长度，晶格常数和棱面夹角表示晶胞的形状和大小。(2)常见金属晶格类型单晶体的各项异性：由于各
2、晶面和各晶向上的原子排列密度不同，因而导致在同一晶体的不同晶面和晶向上的各种性能也不同——各项异性。多晶体tomorrowIgofishingtotheEast.Bossesdon'thavefishtoeat."Positionsoutofafatman:"goingonnowinthepast,theImperialArmycameaftereatingisbad."OldKingsHeadRushthankedthecaptainrushedtothebaseforHongKong,ShenYuezhensa
3、id:"Ithinksowell!"Aboardtheship,toldthroughagain.MonthsProhappymealsfreshlyprepared,Scullchunkspostimmediately.CardthatFushengoftheElvestakecareof:"oldKingsHeadtomorrow,yourfishsuchasweCaptain!""Know"thisistheKing'svoice,byfar.Atnight,theshiptoport,nexttoseeaf
4、ewxieyeofsmallfishingvessels,stopeating.Alexaftereatingtwoadjacentboatsstoppingby.Learnedfromthemouthsoflocalfishermenherehaveisguerrillazones,EastTaihuLakeinfestedwithbandits,Miaoganglandmark,quietatnight,sometimesinthemorningzhenzeJapanDevilssweep,afternoonz
5、henze,Westofguerrillaactivities.Backontheboat,monthlyProactiondecidedbythefirstprogramme,gotoMiaogang,findfocalpointconnector.Gentlyopentheship,sailedintothetracklessYang.MonthsProhaslostitsway,don'tknowdirection,andhadtolettheoldKingwasdriving.OldKingpullingt
6、wooarssaid:"gooddaytoseethestars,cloudydaybyfeel.Youtakeabreak,gotoclassina构词成分。."No,thecabintherewas"grunting...Shout..."snore.Thenextmorning,MiaogangtheLionBridgeamourningfisherman'swoman.Headwrappedinwhitecloth,foot-wearwhiteshoes,sellingfishinafishline.Her
7、aredfloweronthetoeinhisleftfoot,awhitefloweronthetoeofhisrightfoot,whichisajointsign.Womenwereobservedonthestreetthatatobaccostores,postedalotofsmokeonthedoor,thereisnooldknifebrand.ShopkeepersfacingWest,thereareanothertwostrangerslookingaround.MonthsProknowst
8、hisfocalpointhasbeenexposed,shequicklysoldthefishbacktotheLake,getonBoardoftheoldKingsaid:isShenYuezhen,xiaozhengxinthem.Afewdaysago,ShenYuezhenlistentoJonesLangLaSallesaidhisfamil
