Iyo kabhoni yemukati mega yega sintered specimen fracture yakasiyana, ine kabhoni yemukati yeA-2.5 awt.% murudzi urwu, ichigadzira dense zvinhu zvine kunge zvisina pores, iyo inoumbwa neyakafanana yakagoverwa silicon carbide zvimedu uye yemahara silicon. Nekuwedzera kwekabhoni yekuwedzera, zviri mukati me reaction-sintered silicon carbide inowedzera zvishoma nezvishoma, saizi yesilicon carbide inowedzera, uye silicon carbide yakabatana kune imwe neimwe mune skeleton chimiro. Nekudaro, yakawandisa kabhoni yemukati inogona kutungamira nyore kune yakasara kabhoni mumuviri wakanyungudika. Kana iyo kabhoni dema ichiwedzerwa kusvika ku3a, sintering yemuenzaniso haina kukwana, uye dema "interlayers" rinoonekwa mukati.
Kana kabhoni ikaita nesilicon yakanyungudutswa, huwandu hwayo hwekuwedzera huwandu hunosvika 234%, izvo zvinoita kuti iyo microstructure ye reaction-sintered silicon carbide yakanyatsoenderana nekabhoni yemukati mubillet. Kana iyo kabhoni yemukati mubillet idiki, iyo silicon carbide inogadzirwa nesilicon-kabhoni reaction haina kukwana kuzadza pores yakatenderedza kabhoni poda, zvichikonzera kuwanda kwesilicon yakasununguka mumuenzaniso. Nekuwedzera kwekabhoni yemukati mubillet, reaction-sintered silicon carbide inogona kuzadza zvizere pores dzakatenderedza kabhoni poda uye kubatanidza yekutanga silicon carbide pamwechete. Panguva ino, zvirimo zvesilicon yemahara mumuenzaniso zvinodzikira uye kuwanda kwemuviri wakasvibiswa kunowedzera. Nekudaro, kana paine kabhoni yakawanda mubillet, yechipiri silicon carbide inogadzirwa nekuita pakati pekabhoni nesilicon inokurumidza kutenderedza toner, zvichiita kuti zviome kuti silicon yakanyungudutswa ibate toner, zvichikonzera kusara kabhoni mumuviri wakanyorova.
Zvinoenderana nemhedzisiro yeXRD, chikamu chekuumbwa kwekuita-sintered sic ndeye α-SiC, β-SiC uye yemahara silicon.
Mukuita kwekupisa kwakanyanya kuita sintering, kabhoni maatomu anotamira kunzvimbo yekutanga paSiC pamusoro β-SiC neyakanyungudutswa nesilicon α-secondary formation. Sezvo iyo silicon-carbon reaction yakajairwa exothermic reaction ine huwandu hukuru hwekudziya kupisa, kukurumidza kutonhora mushure menguva pfupi yekuzvimirira kwekushisa kwekushisa kunowedzera kubviswa kwekabhoni yakanyungudika musilicon yemvura, kuitira kuti zvidimbu zve β-SiC zvinonaya mumhepo. fomu yekabhoni, nekudaro ichivandudza michina yezvinhu. Naizvozvo, chechipiri β-SiC kukwenenzvera zviyo kunobatsira pakuvandudzwa kwesimba rekukotama. MuSi-SiC composite system, zvirimo zvesilicon yemahara muzvinyorwa zvinodzikira nekuwedzera kwekabhoni yemukati mune mbishi zvinhu.
Mhedziso:
(1) Iyo viscosity yeyakagadzirirwa reactive sintering slurry inowedzera nekuwedzera kwehuwandu hwekabhoni dema; Iyo pH kukosha ndeye alkaline uye zvishoma nezvishoma inowedzera.
(2) Nekuwedzera kwekabhoni yemukati mumuviri, kuwanda uye kubhenda simba rekuita-sintered ceramics yakagadzirirwa nekutsikirira nzira yakatanga kuwedzera uye ndokuderera. Kana huwandu hwekabhoni nhema huri 2.5 nguva yehuwandu hwekutanga, iyo matatu-point kukotama simba uye hukuru density yegirinhi billet mushure mekupindura sintering yakakwira zvakanyanya, idzo 227.5mpa uye 3.093g/cm3, zvichiteerana.
(3) Kana muviri une kabhoni yakawandisa uchinge wanyungudutswa, mitswe uye nzvimbo nhema dze “sandwich” dzichaonekwa mumuviri wemuviri. Chikonzero chekupaza ndechekuti iyo silicon oxide gasi inogadzirwa mukati mekuita sintering haisi nyore kuburitsa, zvishoma nezvishoma kuunganidza, kudzvanywa kunokwira, uye iyo jacking mhedzisiro inotungamira kune kuputika kwebillet. Munzvimbo yakasviba "sandwich" mukati me sinter, kune huwandu hwakawanda hwekabhoni isingabatanidzi mukuita.
Nguva yekutumira: Jul-10-2023