RbiC超声辅助磨削及剩余强度研究.docxVIP

RB．SiC超声辅助磨削及剩余强度研究Study RB．SiC超声辅助磨削及剩余强度研究 Study on Ultrasonic Assisted Grinding of RB-SiC and R℃sidual S缸ength Abstract IIl order to iInproVeⅡle resolution of space mi玎or，me increasiIlg diameter of mirror leads to a greatly increaSing laullchmg cost． 111e pe墒胁aIlce indexes of恤：optical system are seVerely related to the lightweight of mirror．As tlle pref．erred material for tlle spaCe renector，hi曲h鲫dIless aIld brimeness of Im-SiC result i11 poor processing peffomaIlce．A la唱e鲥nding forCe埘U in们duc d锄age into t11e surl沁e layer in processing，which causes the decrease of mirror s臼．engm and eVen f-ailure of me mirror．Therefore，in tms p印er， grind吨experiIIlents of RB-SiC were conducted丽m the ind印endem research锄d deVelopmem ul舰sonic assisted system，comparing the two processillg metllods，、^，itll a11d wittlout ulnDsoIlic vibration．Combined wim the nomal grillding f．0rce，sulface quali钾甜ld subsurf．ace d跚age，tlle residual sn．engm of伊ound material was stumed．The following concluSiongs were obtained： (1)nle nomal咖ding force of ul仃Dsollic assisted酊n血g(UAG)was stLldied systematically．Combined砸t11 the specific conditions，a model of nomal grinding forCe was proposed aIld the orcllogonal experimem of four f．actors aIld f．our leVels waS designed．I沁ge anaysis showed that the innuence of feed rate，grinding deptll，ul旬rasoIlic Vibration amplitude aIld spiIldle speed on grinding force decreased iIl order．The grindiIlg force had negative correlation、Ⅳith ultI．asonic vib阳．tion amplinlde aIld spindle speed，aIld positive correlation 、杭tll feed rate and酣nding dep也．Analysis of v撕ance showed tllat也e ef．fect of feed rate on 咖ding forCe was 11igllly si咖ficant．，nle coemcients aIld meir coIlfidence inteⅣals of regression model were obtained aIld tlle re伊ession results were lligllly sigIlificant． (2)Surface mo印hology，rougllIless and subsurface damage of tlle specimens埘m UAG and conventional grinding(OG)were obseⅣed and measured．The material removal mode of me觚o metllods were bom accompaIlied谢th plastic