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1、南京航空航天大學(xué)碩士學(xué)位論文摘要顆粒介質(zhì)成形是利用固體顆粒作為傳力介質(zhì)進(jìn)行板料成形的一種軟模成形工藝,其主要是利用固體顆粒所具有的良好流動性及體積近似不可壓縮性等特性進(jìn)行板料成形。本課題對顆粒介質(zhì)成形工藝進(jìn)行了理論分析,并選用四種不同直徑的球形陶瓷顆粒作為傳力介質(zhì),對顆粒作為凸模和凹模的兩種顆粒介質(zhì)成形工藝條件下筒形件拉深進(jìn)行研究。結(jié)果表明:軟凸模顆粒介質(zhì)成形時,板料的危險區(qū)域?yàn)榈撞颗c傳力區(qū)之間的過渡區(qū)域;在相同的陶瓷顆粒裝入量下,當(dāng)陶瓷顆粒直徑較大時,隨著陶瓷顆粒直徑的減小,板料的成形極限將會提高。但當(dāng)陶瓷顆粒減少到一定程度時,板料的成形極限不再提高;陶瓷顆粒介質(zhì)裝入量,對板料成
2、形極限有很大影響,隨著陶瓷顆粒裝入量的減小,板料的成形極限將會顯著提高;軟凹模顆粒介質(zhì)成形工藝條件下,相同的反向壓力時使用大直徑陶瓷顆粒能使試件更好的與凸模貼合;對于相同直徑的陶瓷顆粒,則需要使用較大的反向壓力使試件貼模;隨著傳遞到試件表面上的反向壓力增大,試件表面質(zhì)量下降,并降低材料的塑性成形能力。關(guān)鍵詞:顆粒介質(zhì)成形;拉深;脹形;板料I顆粒介質(zhì)成形工藝研究ABSTRACTDrawingtechnologywithsolidgranulesasloadtransfermediumisonecategoryofsofttoolformingtechnologies,sincesol
3、idgranulesarecharacteristicoffavorablefluidityandalmostnon-condensabilityofsolidity.Ceramicgranuleswithdifferentdiameterswereselectedasloadtransfermediumtoinsteadofpunchandcavitydie,andformingexperimentationofcolumnarpartsintwotechnicalconditionswerecarriedoutinthisthesis.Theresultsofexperimen
4、tsshowthatthetransitionsectionfromthebulgingregiontothedrawingregioniseasytoberupturedinthecaseofthesolidgranulesaspunch,andtheforminglimitationofsheetincreasesalongwiththediameterdecreasingwhenthequantityofceramicgranuleisconstant.Whilethediameterofceramicgranuleislargerthancertaincriticalval
5、ue,theforminglimitationofsheetwillnotincrease.Moreover,itisfoundthattheforminglimitationofsheetimprovesobservablywhenthequantityofceramicgranuledecreaseduringformingprocess,ontheconditionofthediameterofceramicgranuleisconstant.Ontheconditionsofthesolidgranulesascavitydie,thefitabilityofsheetca
6、nbeimprovedbyincreasingthediametersofceramicgranulesundertheconstantreversepressure,andfortheceramicgranulesofsamediameterdonebyincreasingthereversepressure.However,thesurfacequalityofpartandtheformabilityofsheetwilldecreasealongwiththeincreasingofreversepressure.Keywords:solidgranulemedium;dr
7、awing;bulging;sheetII顆粒介質(zhì)成形工藝研究圖清單圖1.1液壓成形示意圖?????????????????????????????2圖1.2粘質(zhì)成形示意圖?????????????????????????????4圖1.3橡膠成形示意圖?????????????????????????????5圖1.4軟凸模顆粒介質(zhì)成形???????????????????????????6圖1.5軟凹模顆粒介質(zhì)成形?????????????????????????