Umphefumulo wokugcina okuphakade we-graphite uhlaziya ukugcina nokubaluleka kwezinkothambo zemithombo yezindustria.

Umphefumulo wokugcina okuphakade we-graphite uyahlela ukugcina ngokusebenzisa imikhiqizo yekhesheni yezinsizakalo

Ukuchithwa kwekhesheni nokuhambisana phakathi kwamaphakathi kwe-graphite esincane kune-micron

Ukufaka umthelela wokugqibela kwe-powder yegraphite engeziwe ngokupheleleyo kuyabangela ubungakanani bokuguqula kweminye imithwalo: izimilo ezingaphansi zokugqibela phakathi kwe-layer zegraphene zisiza amapharti ukuthi abulawe ku-ma-thin, ama-flexible sheets. Lezi zi-layer ezibulaweyo zihlaza ngokulinganayo kuzo, zidala indawo engeziwe yokugqibela. Kukho okubalulekile ukuthi le nto iyasebenza ngokwakhe—ukuhlaza kahle kuyabangela ukuthi i-basal planes ezintsha zibonakale, kusiza ukuthi kubhekwe indawo yokugqibela ekhona ngokupheleleyo nakuba kunezimilo ezingaphansi zokugqibela apho izilubricant ezingaphansi zihlwa. Ukukhulu kwe-particle okungaphezulu kwe-micron kusiza ukuthi kubhekwe indawo engeziwe yokuhlaza, kusiza ukuthi ukugqibela kwezimilo kuhle. Ngokubonakalisa kwezifundo zokugqibela ezenziwe ngokupheleleyo, ama-coating ayezegraphite engeziwe ngokupheleleyo ayagcina ukugqibela kwezimilo kusuka ku-0.4 kusukela kungaphezulu kwe-0.08 [Wear, 2022].

Ngani ukukhulu kwe-particle (<1 µm) nokuhlanganiswa kwe-basal plane kugcina ukugqibela kwezimilo

Amaphakathi angaphezulu kwe-1 µm ayagcwalisa izinyathelo zokugcina zomfanekiso ngokuphelele, yenza isilayi sokugcina esihlanu, esifanayo, esisindisayo esikhubaza ukuxhumana kwezinkambo ngokwesibini—umthwalo omkhulu wekugcina ngokuxhumana nokuthi kubhekise kwezinkambo nezinkambo futhi ukuthi kubhekise kwezinkambo ngokukhulu. Uma kufakwa amandla okuhambisa, izinyathelo zokugcina zokugcina zokugcina ziyahlanganisa ngokuzenzakalelayo ngokuphelele kumgomo wokuhambisa, kubonisa ukuthi ukuhambisa kuyasebenza ngokuphelele futhi ukuthi kungabhekise kwezinkambo zokusebenza. Lokhu kusiza ukuthi i-coefficient yemithwalo ibe yizilinganiso zokulinganisa phakathi kwe-0.05–0.08, kubonisiwe ngokusebenzisa izimboni zokuhlanganisa izinkambo ngokwesibini [Tribology International, 2023]. Ngaphandle kwalokho, i-graphite engafanele (ngaphezulu kwe-10 µm) ayinakubonakalisa ukuthi kuyahlukaniswa ngokuphelele futhi kusho kakhulu ukuthi kuyasebenza njengomuntu wokuthi kuyahlukaniswa ngokwesibini, kubhekise kwezinkambo zokugcina. Kuyinto kuphela ukuthi kuyahlukaniswa kwezinkambo zokugcina ngaphezulu kwe-micron futhi ukuthi kuyahlukaniswa ngokwesibini kuyasiza ukuthi kuyasebenza ngokuphelele kanye nokuthi kuyasebenza ngokuphelele kunezinkambo eziningi zokuhambisa.

I-Ultra Fine Graphite Powder iyadlula isikhathi sokusebenza kwesilayi ngokusebenzisa izindlela zokugcina.

I-Load-Bearing Graphite Networks iyadlula ukugcina ngokuhlukaniswa kwezinkambo kwezilayi zokugcina zezinhlangano zezinkambo.

Umbhalo wemphakathi wemithambo yegraphite (≤1 µm) uyadala umkhakha wokugcina, owahlukile kumakhambu amahle wemithambo yepolymers—ngaphandle kwezinye izinkampani ezincane, ozokwenzela ukuthi kubhekwe ngokuphelele kwezinkinga zokuzimela. Amaphakathi akhethekile asegraphite ayadistribuza ukulawula kwemikhumbu ngokulinganayo, ukunciphisa indawo yokuxhumana okwesibonelo futhi ukungqoba ukuchitha kwezinye izinto ezingaphakathi. Kuma-epoxy-based coatings, ukudala kuphela ama-5 wt% wepowder leyi yasusula ukuchitha kwezinye izinto kusuka ku-3.8 × 10⁻⁴ mm³/N·m ku-1.2 × 10⁻⁴ mm³/N·m [Wear, 2022]. Umkhakha wokusebenza wasegraphite wafaka ukuzimela kwemithambo yepolymers, ukongeza ukuphakama kwezinkampani ngo-25–30% ngaphandle kokungqoba ukuzimela. Lokhu kucabanga kabili—ukuthuthukisa imikhumbu futhi ukusebenza njengomthwalo wokuhlanya—kuyenza ukuthi le-coating ibe yisibonelo sokuvikela ukuchitha kwezinye izinto futhi ukuchitha kwezinye izinto ngokuphindeleka kwezinkinga zokuzimela okuphelele, ngokuphelele njengomkhakha wokuvikela okuphindeleka okuhlanya okuvikela isibonelo.

Ukuthuthukisa ukuhlanya ngokuzimela kwezinkinga zokuzimela okuphelele: Idata yokusebenza kwezinto zokusebenza

Kwizindlela zokusebenza eziningi kwezinye izimo zokugcina ngaphandle kwamafutha, umqondiso wemithombo yegraphite enkulu kakhulu uyakunceda ukuba ibe yisibonelo esihle sokubaluleka kude. Kwizicatshulwa zezibalo zase-ASTM G133 zokuguqula isiphephelo esingaphansi kwezibhola, umqondiso wamaphutha we-polyamide-imide owenziwe ngale mpilo yegraphite wabeka isibonelo esihle sokubaluleka kwe-coefficient of friction (COF) esingaba yisi-0.11 emva kokuphinda kabusha kwezibalo zesi-150,000—ngakho-ke umqondiso owayengasoloko wabuka ngokukhanya kwe-COF = 0.48 futhi wafa ngokuphinda kabusha kwezibalo zesi-20,000 [Tribology International, 2023]. Lokhu kubhekise kuzo zokugcina okufana nezibalo zokugcina kwezibhola zegraphite, okuyabeka isibonelo esincane sokugcina esikhanyayo kwenqamulela yezibhola. Lokhu sibonelo siyagcinwa ngokuphinda kabusha ngokusebenza, okunqamula ukugcina kwezinhlobo zezinto zokusebenza noma ukugcina kwezinhlobo zezinto zokusebenza nokugcina kwezinhlobo zezinto zokusebenza. Ukuvumela kwezindawo zokusebenza kwezinkampani zokuhambisa amathuba ayisibonelo sokuthi lokhu kusobala kwezindawo zokusebenza: izintonga zokusebenza ziyakhupha kahle ngokuphinda kabusha kwezintathu ngamaphutha ayo egraphite, okubonisa ukuthi lokhu kusobala kwezindawo zokusebenza zokuphinda kabusha kwezintathu ngamaphutha ayo egraphite.

Ukuhlelwa kwezimpilo zegraphite enkulu kakhulu kwezimpilo zokugcina nokuhlanganisa kwezimpilo zokugcina

Imiphumela Yokugcina Kwezinto Ezihlukene Nokudala Kwemiphumela Yokugcina Phakathi Kwemiphumela Yokugcina

Umpilo wemithi yegrafithi oyinkulu kakhulu (<1 µm) uyakwenzela ukugcina okuphakeme kwezinto ezihlukene ngokusebenzisa amandla asezingeni le-van der Waals emifanekweni yezinto ezihlukene. Lezi ziqembu zokugcina ziyadala imiphumela yokugcina ephakeme—izikhumba, izibhulungu zemikhono, nezindawo eziphelele kwezinto ezihlukene—kumfano wokugcina. Lezi zimpilo ziyasebenza njengamandla okugcina, okuvula ukubambisana ngaphezu kwe-40% futhi okongeza ukufika kwemvula. Okubi kakhulu, iziqembu zegrafithi ezikwenzelwa zingasenza umsebenzi wokuba ngamathuba amabili wezinto ezihlukene, okuvula ukunciphisa ukuzimela nokuphatha kwezinto ezihlukene. Ukuchitha okuphakeme kungenza ukuthi kube phakade ukugcina kwezinto ezihlukene; iziqembu ezingaphansi ziyadala izindawo ezingazange zisebenze, apho umfano wokugcina uyabuyela kuqinisekisa ukuthi ubumbane bungabonakali, okuvula ukufa kahle ngokusebenzisa ukusuka kwezinto ezihlukene noma ngokusebenzisa ukusuka kwezinto ezihlukene.

Izindlela Zokuguqula Isilisa: Ukugcina Kwesilane Nokuguqula Ngamaphuzu Ama-Amino

Ukuguqula kwesikhele kwezinye izinto kusobala ukuthi kubhekene nezinkinga zokugcina nokuhlanganisa. Izinkampani zokugxilisa ezingaphansi—njengokuthi i-3-aminopropyltriethoxysilane—ziyagula futhi ziyaqondana nesikhumba sezinkhomo, zingenisa izinto zokusebenza zezinhlobo zokuphatha okuzokuxhumana ngokuchemicali nesirinzi se-epoxy noma se-polyurethane. Lokhu kwenza umkhakha wokuxhumana kwemithambo, okuyisivumelwano sokuguqula umkhakha wokufaka ukuthi ubheke njengomkhakha wokubeka imiphumela emibi ku-umkhakha wokufaka ukuthi uye kube yinkhomo yokuqonda, okuyisibonelo sokukhulisa umkhakha. Ngokufanayo, ukuguqula ngokuthi kunezinhlobo zokuphatha zokuxhumana ngokwesibhakabhaka kusobala ukuthi kubhekene nezinhlobo zokuphatha eziningi, okunika ukugcina okuphelele okungafani noma kubhekene nokuvutha kabusha ekuphelweni. Izinkhomo eziguguwe zibe nemiphumela yezinye izinto engapheleli, okunika ukuthi zihlale kahle futhi ziyakhiwa ngokulinganayo. Lokhu kwenza ukuthi kukhona ukuvutha kwezindawo zokuphatha ngokuphelele kwe-20–30% futhi ukuthi kunciphiseka kakhulu ukuthi kubhekene nezindawo zokuphatha—okuyisidingo esibalulekile ukuthi kubhekene nezindawo zokuphatha zokuphatha okuphelele futhi ukuthi kubhekene nezindawo zokuphatha zokuphatha okuphelele kwezincwadi zokuphatha.

Imibuzo Evame Ukubuzwa

Yini inkimbinkimbi eyinkulu yokuphatha kwezinkhomo zokuphatha zokuphatha?

Umbhalo wemithambo yegrafithi oyinkulu kakhulu uyenza ukuthi kubheke isibonelo sokulubricathi ngokuthi kusukela kwezinyathelo zegraphene, okuyenza ukuthi kwenziwe indawo engekhona ukuthi kubhekiswe kahle. Lokhu kuyenza ukuthi kubhekiswe amaphansi amasha kuzo zonke izikhathi zokuhambana.

Kungani ubukhulu bekuphakeme kakhulu ekunciphiseni iziqu zokuthi kubhekiswe kahle?

Amaphakeme angaphezulu kwe-micron ayenza ukuthi igrafithi ibe yilapho lapho kunezinyathelo zomhlaba, futhi yenza izindawo ezihlukahlukene ezinamandla okuthi akubhekiswe kahle kwezinyathelo zomhlaba. Amaphakeme amancane futhi ayagcina ngokulinganisa ngokuthi kubhekiswe kahle, okuyenza ukuthi kubhekiswe kahle kwezinyathelo zomhlaba kanye nokunciphisa ukuthi kufakwa imisebenzi yezindawo.

Umbhalo wemithambo yegrafithi oyinkulu kakhulu uyenza kanjani ukuthi kubheke isibonelo sokulubricathi sibe nendlela yokudala?

Lokhu kuyenza izindawo eziphakeme ezinamandla okuthi ziqondise indawo yezindawo, okuyenza ukuthi kunciphiswe ukuthi kubhekiswe kahle kwezinyathelo zomhlaba. Ukusebenza kwalo kubili—ukuthi kubhekiswe kahle njengesolid kanye nokuthi kubhekiswe kahle njengesolid—kuyenza ukuthi kubhekiswe isibonelo sokulubricathi ngokuthi kubhekiswe kahle kwezinyathelo zomhlaba zokuhambana ngokuthi kubhekiswe kahle kwezinyathelo zomhlaba.

Izinkinga ziphi zokuthi kubhekiswe kahle kwezinyathelo zomhlaba zegrafithi oyinkulu kakhulu?

Ipowdla liyagqamuka ngokuzenzakalelayo ngokuthi kunezimali zokugqamuka kwe-van der Waals ezinkulu, okubangela ukuthi kubhekwe izinkinga zokugqamuka phakathi kwezinye iziqephu, okuhambisana nokungafaneleka kwezinkinga zokugqamuka kanye nokungafaneleka kwezinkinga zokuphatha kwezinqamuzi. Ukushekelwa ngokuzimisa okuphakeme kuyasebenza kungenza ukuthi izinkinga zokugqamuka zizamekile ngokuphelele.

Ukuguqula isibonelo sikhuluma njani ngokuvuselela ukushekelwa kwe-graphite?

Izindlela zokuguqula isibonelo, njengezindlela zokugqamuka kwe-silane noma ukuguqula ngokusebenzisa i-amino, zenza izihlukanisi zokugqamuka phakathi kwezinye iziqephu zwe-graphite nezinqamuzi. Lokhu kusinika ukushekelwa okuphakeme, kunciphisa izinkinga, futhi kubusa izinkinga zokuphatha kanye nezinkinga zokusebenza kwezinqamuzi.