Isicelo seUmhlaba ongavamileEzintweni Ezihlanganisiwe
Izakhi zomhlaba ezingavamile zinesakhiwo se-elekthronikhi esingu-4f esiyingqayizivele, umzuzu omkhulu kazibuthe we-athomu, ukuhlanganisa okuqinile kokuphonswa nezinye izici. Lapho kwakhiwa ama-complexes nezinye izakhi, inombolo yabo yokuxhumana ingahluka kusuka ku-6 kuya ku-12. Izinhlanganisela zomhlaba ezingavamile zinezinhlobonhlobo zezinhlaka zekristalu. Izakhiwo ezikhethekile ezibonakalayo namakhemikhali zomhlaba ongavamile ziwenza asetshenziswe kabanzi ekuncibilikisweni kwezinsimbi ezisezingeni eliphezulu nezingezona insimbi, ingilazi ekhethekile nezitsha zobumba ezisebenza kahle kakhulu, izinto zikazibuthe ezihlala unomphela, izinto zokugcina i-hydrogen, izinto zokukhanya nezingilazi, izinto zenuzi. , nezinye izinkambu. Ngokuthuthuka okuqhubekayo kwezinto eziyinhlanganisela, ukusetshenziswa kwemihlaba eyivelakancane kuphinde kwanda emkhakheni wezinto eziyinhlanganisela, kudonsela ukunaka okusabalele ekuthuthukiseni izakhiwo zokuxhumanisa phakathi kwezinto ezihlukene.
Izinhlobo zokusetshenziswa eziyinhloko zomhlaba ongavamile ekulungiseleleni izinto eziyinhlanganisela zihlanganisa: ① ukungezaizinsimbi zomhlaba ezingavamileekuhlanganiseni izinto; ② Engeza ngendlela yeama-oxide omhlaba angavamilekumpahla eyinhlanganisela; ③ Ama-polymers afakwe noma ahlanganiswe nezinsimbi zomhlaba ezingavamile kuma-polymers asetshenziswa njengezinto ze-matrix ezintweni eziyinhlanganisela. Phakathi kwalezi zinhlobo ezintathu ezingenhla zokusetshenziswa komhlaba okungavamile, amafomu amabili okuqala engezwa kakhulu enhlanganisela ye-matrix yensimbi, kuyilapho eyesithathu isetshenziswa kakhulu kuzinhlanganisela ze-polymer matrix, kanye nenhlanganisela ye-ceramic matrix yengezwe ngokuyinhloko efomini lesibili.
Umhlaba ongavamileikakhulukazi isebenza ku-metal matrix kanye nenhlanganisela ye-ceramic matrix ngendlela yezithasiselo, iziqinisi, nezithasiselo ze-sintering, ithuthukisa kakhulu ukusebenza kwazo, inciphise izindleko zokukhiqiza, nokwenza ukusetshenziswa kwayo kwezimboni kwenzeke.
Ukwengezwa kwezinto ezingavamile zomhlaba njengezithasiselo ezintweni eziyinhlanganisela ikakhulukazi kudlala indima ekuthuthukiseni ukusebenza kwesixhumi esibonakalayo sezinto eziyinhlanganisela nokuphromotha ukucolisiswa kwezinhlamvu ze-matrix yensimbi. Indlela yokwenza imi kanje.
① Thuthukisa ukumanzisa phakathi kwe-matrix yensimbi nesigaba sokuqinisa. I-electronegativity yezakhi zomhlaba ezingavamile iphansi uma kuqhathaniswa (uma kuncane ukutholakala kwe-electronegativity kwezinsimbi, yilapho kusebenza khona i-electronegativity yezinto ezingezona ezensimbi). Isibonelo, u-La ungu-1.1, u-Ce ungu-1.12, futhi u-Y ungu-1.22. I-electronegativity ye-common base metal Fe yi-1.83, i-Ni ingu-1.91, futhi i-Al ingu-1.61. Ngakho-ke, izakhi zomhlaba ezingavamile zizokhanga ngokukhethekile emingceleni yokusanhlamvu ye-matrix yensimbi kanye nesigaba sokuqinisa phakathi nenqubo yokuncibilikisa, inciphisa amandla azo okusebenzisana nayo, ikhulise umsebenzi wokunamathela wesixhumi esibonakalayo, inciphise i-engeli yokumanzisa, futhi ngaleyo ndlela ithuthukise ukumanzi phakathi kwe-matrix. kanye nesigaba sokuqinisa. Ucwaningo luye lwabonisa ukuthi ukungezwa kwe-element ye-La ku-matrix ye-aluminium kuthuthukisa ngempumelelo ukumanzisa kwe-AlO ne-aluminium liquid, futhi kuthuthukisa i-microstructure yezinto ezihlanganisiwe.
② Thuthukisa ukucolisiswa kwezinhlamvu ze-matrix zensimbi. Ukunyibilika komhlaba ongavamile kukristalu yensimbi kuncane, ngoba irediyasi ye-athomu yezinto ezingavamile zomhlaba inkulu, futhi irediyasi ye-athomu ye-matrix yensimbi incane kakhulu. Ukungena kwezinto ezingavamile zomhlaba ezine-radius enkulu ku-matrix lattice kuzodala ukuhlanekezela kwe-lattice, okuzokhuphula amandla esistimu. Ukuze kugcinwe amandla amahhala aphansi, ama-athomu omhlaba ayivelakancane angacebisa kuphela emingceleni yokusanhlamvu engajwayelekile, okuthi ngezinga elithile ivimbele ukukhula okukhululekile kwezinhlamvu ze-matrix. Ngasikhathi sinye, izakhi zomhlaba eziyivelakancane ezithuthukisiwe zizophinde zikhangise ezinye izakhi ze-alloy, zikhulise i-gradient ye-alloy elements, okubangela ukuba ingxenye yendawo ingapholi kahle, futhi ithuthukise umphumela we-nucleation ohlukahlukene we-matrix yensimbi ewuketshezi. Ukwengeza, ukupholisa okuphansi okubangelwa ukuhlukaniswa kwe-elemental kungabuye kukhuthaze ukwakheka kwezinhlanganisela ezihlukanisiwe futhi kube yizinhlayiya ze-nucleation ezisebenzayo, ngaleyo ndlela kukhuthaze ukucwengwa kwezinhlamvu ze-matrix zensimbi.
③ Hlanza imingcele yokusanhlamvu. Ngenxa yokuhlobana okuqinile phakathi kwezakhi zomhlaba ezingavamile kanye nezakhi ezifana no-O, S, P, N, njll., amandla amahhala ajwayelekile okwakheka kwama-oxides, ama-sulfide, ama-phosphides, nama-nitrides aphansi. Lezi zinhlanganisela zinezinga eliphakeme lokuncibilika kanye nobukhulu obuphansi, ezinye zazo ezingasuswa ngokuntanta phezulu kusuka ku-alloy liquid, kanti ezinye zisakazwa ngokulinganayo ngaphakathi kokusanhlamvu, ukunciphisa ukuhlukaniswa kokungcola emngceleni wokusanhlamvu, ngaleyo ndlela kuhlanzwe umngcele wokusanhlamvu futhi ukuthuthukisa amandla ayo.
Kumele kuqashelwe ukuthi, ngenxa yomsebenzi ophezulu kanye nephuzu eliphansi lokuncibilika kwezinsimbi zomhlaba ezingavamile, lapho zengezwa kwinhlanganisela ye-metal matrix, ukuthintana kwabo ne-oxygen kudinga ukulawulwa ngokukhethekile ngesikhathi senqubo yokwengeza.
Izinqubo eziningi ziye zafakazela ukuthi ukwengeza ama-oxide omhlaba angavamile njengezinzinzisi, izinsiza ze-sintering, nezilungisi ze-doping kumatrix ehlukene yensimbi kanye nenhlanganisela ye-ceramic matrix kungathuthukisa kakhulu amandla nokuqina kwezinto, kunciphise izinga lokushisa elishisayo, futhi ngaleyo ndlela kunciphise izindleko zokukhiqiza. Indlela eyinhloko yesenzo sayo imi kanje.
① Njengesengezo se-sintering, singaphromotha i-sintering futhi sinciphise i-porosity ezintweni eziyinhlanganisela. Ukwengezwa kwezithasiselo ze-sintering ukukhiqiza isigaba soketshezi emazingeni okushisa aphezulu, ukunciphisa izinga lokushisa le-sintering lezinto eziyinhlanganisela, ukuvimbela ukubola kwezinga lokushisa eliphezulu kwezinto ngesikhathi senqubo yokucwilisa, nokuthola izinto eziyinhlanganisela eziminyene ngokusebenzisa i-liquid phase sintering. Ngenxa yokuzinza okuphezulu, ukuguquguquka okubuthakathaka kwezinga eliphezulu lokushisa, kanye namaphoyinti aphezulu ancibilikayo nabilayo ama-oxides omhlaba ayivelakancane, angakwazi ukwenza izigaba zengilazi nezinye izinto zokusetshenziswa futhi akhuthaze ukucwiliswa kwe-sintering, okuwenza abe isithako esisebenzayo. Ngasikhathi sinye, i-earth oxide engavamile ingakha isixazululo esiqinile nge-ceramic matrix, engakhiqiza amaphutha ekristalu ngaphakathi, ivule i-lattice futhi ikhuthaze ukucwiliswa.
② Thuthukisa i-microstructure futhi wenze ngcono usayizi wokusanhlamvu. Ngenxa yokuthi ama-oxide omhlaba angeziwe angeziwe atholakala ikakhulukazi emingceleni yokusanhlamvu ye-matrix, futhi ngenxa yomthamo wawo omkhulu, ama-oxide omhlaba ayivelakancane anokumelana okuphezulu nokufuduka esakhiweni, futhi avimbela ukufuduka kwamanye ama-ion, ngaleyo ndlela anciphise ukufuduka. izinga lokufuduka kwemingcele yokusanhlamvu, elivimbela ukukhula okusanhlamvu, futhi livimbele ukukhula okungavamile kokusanhlamvu ngesikhathi sokushiswa kwezinga lokushisa eliphezulu. Bangakwazi ukuthola okusanhlamvu okuncane futhi okufanayo, okuhambisana nokwakheka kwezakhiwo eziminyene; Ngakolunye uhlangothi, ngokufaka ama-oxides angavamile emhlabeni, angena esigabeni sengilazi yomngcele wokusanhlamvu, athuthukise amandla esigaba seglasi futhi ngaleyo ndlela afeze umgomo wokuthuthukisa izakhiwo zemishini yezinto ezibonakalayo.
Izakhi zomhlaba ezingavamile ezinhlanganisela ze-polymer matrix zibathinta kakhulu ngokuthuthukisa izakhiwo ze-polymer matrix. Ama-earth oxides angavamile angakhuphula izinga lokushisa lokubola lama-polymers, kuyilapho ama-carboxylates ayivelakancane angathuthukisa ukuqina okushisayo kwe-polyvinyl chloride. I-doping polystyrene enezinhlanganisela zomhlaba ezingavamile ingathuthukisa ukuzinza kwe-polystyrene futhi ikhulise ngokuphawulekayo amandla ayo omthelela namandla okugoba.
Isikhathi sokuthumela: Apr-26-2023