Ukufunda ngokuchazwa kwesimo sendiza yenthalpi (CTE) nokuthi kubalulekile kanjani

Izinguquko zokunweba kwezimali, noma CTE ngokufuphi, kuvamile kusho ukuthini umlando uzoba khona uma izinkimbili ziphakama. Amadhamende angcono ngoba akhula kude, kuphela kungu-0.8 kuze kube ngu-1.2 ngamazinga amathupha kuye Kelvin. Ngokulinganisa lokhu nozidingo olunjani lwezinyo njenge-cobalt noma iindlela ezithile ze-steel alloys eziphakama phakathi kwe-5 kuye kube ngu-15 okuningi kungeza madhamende. Uma sibizwa ngemisebenzi ye-laser welding, izinto ziyashisa kakhulu. Umthubi ophakeme kule miphumela ungafika kumaqondo phakathi kwe-1500 kuye kube ngu-2000 degrees Celsius. Lokhu okukhulu kokulinganisa kwezinkimbili kwenza imiba engcono emkhawulweni apho idhamende ihlangana nezidingo. Uma akuzenzeki ngendlela efanelekileyo, le nkqubo yezinkinga ikhombisa izinkinga ezingenjalo ebalulekileyo ephazanyiswa yonke into ngaphambi kokuba igunya likhululwe ekusebenzisweni kwempilo.

Kungani Ukulinganisa Kwe-CTE Kumele Kuwuchungechunge Lomnotho Wamandla Wezixhumanisi Ze-Diamond

Ukulungiselela kuka-CTE akuyona into ebalulekile kuphela kodwa yona maphakade esibalulekile uma sifuna ukuzivikela kusiphaluketho sobuqhubi. Umdeli wokwaziswa owabaliswe ngo-2022 yi-Journal of Materials Processing Technology ubonisa into engalunganga ngokuphelele mayelana nezinqamuzi ezalanyanyelwe ngolaser. Xa kwakukhona ukwahlukana kuka-CTE okungaphezu kuka-3 ppm/K phakathi kwezinto, lezi zinqamuzi zazinazo izahluko ezaningi kakhulu emva kwalokho kuzahlukaniswa kwezinkwa. Kutheni uma izinto zika-diamond ziyakhula ngendlela eyahlukene kwezinye? Ithimu lesheya eliphindwe ngaphezu kuka-400 MPa ekugcineni. Lokhu kungaba yisizathu sokuba izindlela zika-diamond zithunyelwe noma isibamba sezingxenye esilawuzeke. Akuyisidingo ukuthi amakhampini enkululeko aqale ukwenza ukulungiselela kuka-CTE njengesidingo xa kuthathwa izahluko kanye nezinyathelo eziphakeme kumsebenzi wabo wokudluliswa ngolaser.

Ukwehluka Kwesimiso Ngokuhlanganiswa Kuka-CTE Ngenkathi Yasezinkwini

Xa izinto zihlukunyezela kahle emva kokugaya, i-stress esizungulweni siqala ukubonakala ngoba umfanekiso ophawuliwe unyibilika kakhulu kunadindima. Ukubheka i-models ze-element eziyinkimbinkimbi kubonisa ukuthi kukhona ubuchwepheshe obukhulu kwiindlela zedindima lapho amandla aqhubeka akhiqizwa apho amandla ethu ekhiqizwa. Le miba ihluka kahle ngexesha xa i-thools iyasebenza ngezinga eliphakade lokuphakama nokuhlukunyezela okufana nezinto ezahlukene kumsebenzi wokugaya. I-stress echasisa iyashisa isixhobo phakathi kwamathuba, eyenzela ukuthi adindima abe ngu-graphite noma afile kabani. Ngokwahlukana, i-thools ezinzululwayo ngokusekelwe kwi-coefficient yokunyibilika kwinga ziyagcina adindima ngendlela efanelekileyo. Izivivinyo kubonisa ngempela ukuthi zicinga malunga ne-92% yeziko lesondlo sabo nangona zaziguga ngeminyaka engama-10,000 yenkinga yokushiswa.

Ithebhu

Imithombo yedatha: IsiJeli saMacholo weZibalo (2022), Izibalo Ezininzi Ze-Injiniya (2023)

Ukakhekelwa Kwesithunzi Se-Stress Ngenkathi Kugcwaliswa: Izindlela Nezimpendulo

Ukuthi I-Stress Zezithunzi Zikhikeya Kanjani Ngenkathi Kudwebeka Ngolaser Ne-Gcwaliseka Ngokushesha

Lapho kusheshwa amathuluzi edayimane nge-laser, kuba nokucindezeleka okusele ngenxa yalezi zingxabano ezinkulu zokushisa phakathi kwezinto ezihlanganisiwe ezishisiwe nezinhlayiya zedayimane zangempela kuyo yonke inqubo yokusheshi. Inkinga iba yimbi nakakhulu njengoba indawo yokushisela ipholile ngoba izingxenye ezihlukene zipholile ngejubane elihlukile, kwakheka izindawo lapho ezinye izingxenye zidonswa khona kuyilapho ezinye zicindezelwa. Amadayimane anenani eliphansi kakhulu lokwanda okushisayo elicishe libe yingxenye eyodwa yesigidi nge-Kelvin, okuyinto ephansi kakhulu kunalokho esikubona kuma-alloys amaningi okuhlangana akhula kakhulu, ngokuvamile angaphezu kuka-12 ppm/K. Lo mehluko omkhulu usho ukuthi amadayimane ayaqina ngendlela ehlukile kunezinsimbi zawo lapho Empeleni, lokho kuphakeme kunalokho izibopho ezijwayelekile ze-cobalt ezingakwazi ukukuphatha ngaphambi kokuba ziqale ukwehluleka. Lezi zinhlobo zokucindezeleka zisebenza kakhulu ezindaweni lapho ukubanda kwenzeka khona ngokushesha okukhulu, ngezinye izikhathi ngokushesha kuka-1000 degrees Celsius ngomzuzwana ngokweminye imilinganiso.

Amathuba akhelela kweMicrostructural Kusuka KuBuchwepheshe Bukhuni Ngama-Coefficient of Thermal Expansion (CTE)

Xa kukhona ukungqamana kwe-coefficient yekhuni ngaphakathi kwemithombo, kuyashisa umgodi wokuthobha kumadeko ekhokhelwa. Lokhu kwenza amabhonkolo amancane nezindawo zokudondoshelwa ezihamba phambili ezingeni le-diamond ngexesha. Mcinezela izibindi ezisekelwe kwi-nickel. Ukuba kuncipha kakhulu, into engachabikiyo ebizwa ngokuba yi-Ni3B ihlala kuyo. Izifundo zibonisa ukuthi lokhu kuyenza umlango ube ngu-40 iphasente engaphantsi kwemini xa kufikwa ekucothuleni kunazo enocingo olunciphayo. Kutheni okulandelayo? Lezo zindawo zomgodi oshisayo ziyakha indawo apho ibuchwepheshe buhlanjiswa ngenxa yokusebenzisa ngempela. Futhi yintoni? Lokho ibuchwepheshe kuhanjiswa kakhulu kanjalo kakhokelela ukuthi i-diamonds zithintwe kuzinqamlezo zokugcina, okungafuneki.

Ukukhokelela Kwesivinini Sokucindezelwa Ekugcineni Ibhondi

Uma ukugcina kweglasi kusenziwa ngokushesha kakhulu (ngaphezu kuka-10,000 K ngosuku), kwenza izinkinga ngezilinganiso zokunweba kanti umongo wakhiwa amasuntswana amancane kakhulu angaphenduli kangako. Lokhu kuyenza ukuthi ukugcina kube khanyayo kodwa kube lula kakhulu ekulondolozeni izixwayiso, okusho ukuthi isixwayiso sikhulu sitholakala endaweni ephakeme kakhulu ezingxenyeni zezindilinga ezimfushane, njengoko-50 ukuya ku-100 micrometers. Indlela engcono iyafaka phakathi ukupheliswa okubophelelayo okungekho mkati ka-300 ukuya ku-500 degrees Celsius ngosuku. Le ndlela yamandla enza ukuthi kunciphise isixwayiso esisemva ngama-35 kabusha ngaphandle kokuthintela indlela eyinhloko ethunyelwe, yenza into ekugcineni ihlangabezane kakhulu.

Kulinganiswa Nezogcina Ngilaser: Ukusebenza Ngesixwayiso Sokushisa

Ukulinganiswa Okuhlanganisiwe Kwemigqa Ye-Diamond Ezigcinwa Kwangaphandle Nezogcina Ngilaser

Izixhobo zediamond eziqhotyoshelwe zisebenzisa izintlangu ezithanda kakhulu ukuze ziqhotyoshe. Lezi ngcamango zihlukaniswa ngendlela yokuqhuma kodwa ngokuvamile azifuni indlela efanayo nezobuchwepheshe abahlanganisa. Ukunxibelelana kwelase laser kusebenza ngendlela eyahlukene. Xa usebenzisa le ndlela, izobuchwepheshe zombuso zithiyaniswa ukwenza uhlangano lwemetalurgiya ngqo. Ngokwesicwangciso esiphulileyo eJournal of Manufacturing Processes ngo-2022, lezi zinxiba zingafinyelela phakathi kuka-92% ne-97% yobuchwepheshe bwebomu. Izimpendulo zezenzo zibonakala ngokwengezeke kwegunya. Iqhotyoshelo lasekhohlo linethemba lokuthutha kakhulu kakhulu emaphandleni awo alaqhotyoshayo kunalokho okunxibeke kase-laser, lithintela ngakumbi kakhulu.

Ukuchazwa Kweziphumayo: Ukuphulwa Kwediamond Ekuqaleni Kwezixhobo Zokugcina Ngoba Ye-Coefficient (CTE) Yenguqu

Xa izinkuni zodiamond zakhula ngama-0.8 amaphuzu ngalokungu-1 million ngeKelvin kunokuthi kwezincunzi ze-steel ezhakamela kakhulu phakathi kwe-11 ne-14 ppm/K, lokhu kuchazwa kwenza kunezinkinga ezikhulu zomthwalo wokugayaya ngqo emkhawulweni. Ngemva kwalokho kwizindlela zokushisa ezingcono, le mithwalo ingasephinde iphumele 450 megapascals. Kusenzekani ngoku? Amaphethini aqala ukudalwa emathupheni akho kanye nokuthutha kuyo kuhlobo loba izinkuni zodiamond zihlupha kancane kancane. Uma ubheka imizekelo yombuso ngamandla okugaya komphethini ngamadividi angahliwa kumjikelezo, kuchaza into engiyasendabeni. Umdla wokusebenza kwangena ovela ku-Industrial Diamond Review ekupheleni kwe-2023 wabona ukuthi izixhumanisi ezilaser welded zahlinywa izinkuni zabo ngama-23 iphasenthi ngaphezulu kwezobumba eziphathelene nazo lomlando wokushisa.

Ubusizo Bemdla: Imiphumela Yokusisha KuMthwalo Wokuxhumaniswa

Kukhona uhlanganiso olucacile phakathi kwe-CTE mismatch nezinkinga zezinkinga ephathelene nethenkinga enjengomgwa welogarithmic. Isibonelo, yona yona iphamphilethi 1 ppm/K ekuphazanywayo kwe-CTE kushiywa kuthinta amathuba okuthembeka ngaproximately 19%. Ukubheka emva kwezinye izinsiza, sibona ukuthi kunezinkinga eziphindwe ngaproximately 68% eziphazanywayo eziphazanywayo uma lezi zinkinga eziphazanywayo ziyekwa ngaphezulu kwe-3 ppm/K ngokwesicelo sase-Journal of Materials Processing Technology ngenyanga ya-2022. Okuthintekayo kukuthi phezu kwe-41% kwezi zinkinga zibonakala ngaphakathi kweminyaka engu-50 yokuchithwa kwezinkwa futhi. Isimemo sokuhlelekile kukuthi izixhumanisi zomlando zazigcinwa zihlanzekile kakhulu kusasa. Abasebenzi bamanje bangabuka indlela esebenzayo yomthwalo ngamandla angaphansi kwe-5 microns, lokhu kuthintela ukuthi bafundeni ubude bezinkinga eziphakeme kakhulu ephakathi kwe-0.2 kuye kwe-0.35 mm ukulawula konke lokhu kumthwalo wokuchithwa.

Ithebula 1: Izilinganiso zokusebenza zama-interface amathuluzi edayimane ngaphansi kwe-ISO 15614 thermal cycling protocol

Amasu athuthukile okufanisa ama-CTE ekwakhiweni kwamathuluzi anamuhla

Ubuchwepheshe besimanje bokwakha amathuluzi busebenzisa izindlela ezintathu eziphambili zokubhekana nokungalingani kokwanda kokushisa phakathi kwamadiyamanti nezinto ezihlanganisiwe.

Izingqimba eziphakathi ezihlelwe ukusebenza ukuze kuncishiswe ukungalingani kokunwetshwa kokushisa

Izindawo zokuguqulwa ezinamakhasi amaningi ezinamanani e-CTE akhulayo kancane kancane zinciphisa ukucindezelwa kobuso ngo-42% uma kuqhathaniswa nokuhlangana kwezinto eziqinile (Journal of Manufacturing Processes, 2023). I-tungsten-copper composites ehlukaniswe kusuka ku-4.5 ppm/K kuya ku-8 ppm/K ibonisa ukuqina okuphawulekayo kwamandla emishini yokusika efakwe idayimane elawulwa imijikelezo yokushisa engu-300°C700°C.

Ukwakhiwa Okuqhutshwa Ukufaniswa: Ukudlulela Ngale Kwezinqubo Zokubopha Okuyisisekelo

Ukuhlaziywa kwezinto eziphelile (FEA) manje kubikezela ukugxila kokucindezeleka kwe-interfacial nge- ± 5% ukuphambuka kwedatha yokuhlola, okwenza ukufaniswa kwe-CTE okunembile ngaphambi kokwenza uhlobo lwe-physical prototyping. Ucwaningo lwango-2023 lwabonisa ukuthi amalunga alungiselelwe ukufaniswa ayakwazi ukumelana nemijikelezo yokushisa ephindwe kathathu kunamadoda avamile.

Ukuqamba Okuthuthukisa Ukuqina Kwengxenye Ephakathi Nokushisa

Izingqimba zensimbi ezivuthayo ezifana nama-alloys e-chromium-vanadium (CTE: 6.2 ppm/K) zakha izixhumi ezihambisanayo phakathi kwedayimane (1.0 ppm/K) nama-matrix wensimbi (12 ppm/K). Ukuhlolwa kwensimu kwembula ukuthi amathuluzi agqokiwe agcina ama-91% wokugcinwa kwedayimane lawo lokuqala ngemuva kwamahora angama-500 ekusetshenzisweni kokusika igraniteukuthuthuka okungama-68% kunamamodeli angagqokiwe (Journal of Materials Processing Technology, 2022).