Yintoni Uzinzo Lobushushu?

Uzinzo lobushushu lubhekiselele kubuchule besixhobo okanye benkqubo ukugcina iipropati ezingaguqukiyo kunye nokusebenza kuzo zonke iimeko ezahlukeneyo zobushushu. Olu phawu lumisela ukuba into imelana kangakanani na nokuthotywa, utshintsho lwemilinganiselo, okanye utshintsho olusebenzayo xa ibekwe kubushushu okanye kubanda. Uzinzo lobushushu bulinganiswa ngokubeka esweni ukutenxa kwipropathi ngokuhamba kwexesha kumaqondo obushushu athile, ngokuqhelekileyo abonakaliswa njengokwahluka kwepesenti kumaxabiso asisiseko.

Uzinzo lobushushu lusebenza kumgaqo wokuba izinto zingena emzimbeni kunye notshintsho lweekhemikhali xa amandla obushushu etshintsha izakhiwo zemolekyuli. Kwinqanaba leathom, ukunyuka kwamaqondo obushushu kubangela ukuba iibhondi zemolekyuli zingcangcazele kakhulu, okunokukhokelela ekwaphulweni kwebhondi okanye uhlengahlengiso.

Ukuzinza kwayo nayiphi na imathiriyeli ixhomekeke kumandla ayo okuvula{0}}awona mandla afunekayo kutshintsho lwesakhiwo. Izinto eziphathekayo ezinamandla okusebenza aphezulu zixhathisa ukuthotywa kwe-thermal ngokufanelekileyo. Umzekelo, iiseramics zidla ngokubonisa uzinzo oluphezulu lobushushu xa kuthelekiswa neepolima ngenxa yokuqina kwe-ionic kunye ne-covalent bond.

Iindlela ezimbini eziphambili zilawula ukuzinza kobushushu: iziphumo ezibuyiselwa umva (njengokwandiswa kwe-thermal) kunye neziphumo ezingenakuguquleka (ezifana nokubola okanye ukuguquka kwesigaba). Iinguqu ezibuyiselwa umva zivumela izixhobo ukuba zibuyele kwimeko yazo yangaphambili xa ubushushu buqhelekile, ngelixa iinguqu ezingenakuguqulelwa ziguqula ngokusisigxina iipropati eziphathekayo.

Ii-coefficients zobushushu zilinganisa indlela iipropati ezitshintsha ngayo ngeqondo lokushisa. Isixhobo esinomlinganiso weqondo lokushisa we-0.001 / idigri ifumana utshintsho lwepropathi ye-0.1% kwi-10℃degrees. Ii-coefficients ezisezantsi zibonisa ukuzinza okungcono.

Temperature Stability

Umahluko wokuSkena ngeKhalorimitha (DSC)isebenza njengomgangatho wegolide wovavanyo lozinzo lwe-thermal. Le ndlela yokulinganisa ubushushu bungena okanye buphuma kwisampulu njengoko ubushushu butshintsha ngesantya esilawulwayo, ngokuqhelekileyo i-10℃/ min. I-DSC ichonga amaqondo obushushu abalulekileyo aquka uguqulo lweglasi (Tg), indawo yokunyibilika, kunye nokuqala kokubola. Indlela ibonelela amaxabiso amandla okuvula ngokuchanekileyo ngaphakathi ±2%.

Uhlalutyo lweThermogravimetric (TGA)ilandelela utshintsho olukhulu phantsi kobushushu obulawulwayo. Uphononongo luka-2024 olupapashwe kuNxibelelwano lweNdalo lubonise ukuba i-TGA inokubona ukuthotywa kweqondo lokushisa elichanekileyo ukuya kwi-0.5 degree. Ubuchwephesha bungqineka buxabiseke kakhulu kwizinto ezibolayo ngaphandle kokunyibilika okubonakalayo, okunje ngeepolima kunye nemixube.

Iimvavanyo zokuguga ze-Isothermalukuveza imathiriyeli kumaqondo obushushu aphakamileyo ahlala ehleli ixesha elongeziweyo{0}}kaninzi 1,000 ukuya 10,000 iiyure. Iinjineli zibeka iliso kugcino lwepropathi ngamaxesha athile, zibala amaxabiso okuthotywa ngeArrhenius equations. Le ndlela iqikelela{7}}uzinzo lwexesha elide ukusuka kwidatha ekhawulezileyo{8}}yexesha elifutshane.

Imiba yozinzo lobushushu idla ngokuxela amaxabiso ngamaxesha amabini: ixesha elifutshane ({0}}iyure e-1) kunye nexesha elide{2}}nexesha (iiyure ezingama-24 nangaphezulu). Kwizinto zombane ezichanekileyo, abavelisi banokuchaza uzinzo njenge-±0.001℃kwithuba elongeziweyo, ngelixa imathiriyeli yefektri inokuvumela ±5% ukwahluka kwepropathi kuluhlu lwabo lokusebenza.

Ixesha lokwenene{0}}lokujongwa kobushushuisebenzisa abenzi boluvo abafakelweyo ukulandelela uzinzo ngexesha lokusebenza. Iinkqubo eziphezulu zisebenzisa i-thermistors okanye i-retance detectors (RTDs) kunye namaxesha okuphendula phantsi kwe-100 millisecond, eyenza ulawulo oluchanekileyo kwizicelo ezifuna ukuzinza kwe-millidegree.

Ukwakhiwa kweekhemikhalingokusisiseko imisela ukuziphatha thermal. Iikhompawundi ze-Inorganic zikholisa ukodlula imathiriyeli ephilayo{1}}i-aluminiyam oxide igcina uzinzo ukuya kutsho kwi-1,800 degree, ngelixa uninzi lwe-organic polymers luthoba ngaphantsi kwe 400 degree. Ubukho beebhondi ezingaxutywanga, izakhiwo ezinevumba elimnandi, okanye iiheteroatom zinefuthe kakhulu kwiindlela zokubola.

Uyilo lwemolekyuliidlala indima ebalulekileyo. Iipolima ezidityanisiweyo zibonisa uzinzo olongeziweyo xa kuthelekiswa namatyathanga anqamlezileyo kuba ii-crosslinks zithintela intshukumo yemolekyuli. Uphononongo luka-2023 kwiiMathiriyeli eziPhakamileyo zafumanisa ukuba ukunyuka kwe-crosslink density ukusuka kwi-10% ukuya kwi-30% kuphuculwe ukuzinza kwe-thermal malunga ne-60℃kwi-epoxy resins.

Umoya we-Ambientichaphazela kakhulu amazinga okuthotywa. Iimeko-bume ze-oxidative zikhawulezisa ukophuka{1}}izinto ezizinzile ukuya kwi-300℃kwi-nitrogen zinokusilela kwi-200℃emoyeni. Ezinye izicelo zifuna umoya ongasebenziyo okanye iimeko zevacuum ukugcina uzinzo kumaqondo obushushu aphezulu.

Umxholo wokufumaichaphazela ukuzinza komzimba kunye neekhemikhali. Iimolekyuli zamanzi zinokwenza i-hydrolysis reaction okanye iguqule amaqondo obushushu besigaba. Izinto ezixuba amayeza zihlala zifuna ukugcinwa ngaphantsi kwe-25℃kunye ne-60% yokufuma okuhambelanayo ukugcina uzinzo.

Uxinzelelo lomatshiniidityaniswe nobushushu idala iziphumo zokuthotywa kwe-synergistic. Izinto eziphantsi komthwalo we-tensile zibonisa ukuzinza okuphantsi kwe-thermal kuneesampuli ezingagxininisi. Le nto ibaluleke kakhulu kwizicelo zesakhiwo apho amacandelo ngaxeshanye afumana ukulayishwa kwe-thermal kunye noomatshini.

Ukuhamba ngebhayisekile okushushuibalulekile njengobushushu obupheleleyo. Icandelo elimelana ne-100℃elizinzile linokusilela xa ibhayisekile phakathi kwe-25℃kunye ne-100℃ngokuphindaphindiweyo ngenxa yokudinwa kwe-thermal. Inani lemijikelo yokusilela lilandela amandla -ubudlelwane bomthetho kunye nokwahluka kobushushu beamplitude.

Temperature Stability

Amacandelo e-elektroniki avelisa ubushushu obuninzi ngexesha lokusebenza, okwenza ukuzinza kobushushu kube yeyona nto iphambili ekuthembekeni. Iimicroprocessors zangoku zivelisa ubushushu obugqithisa kwi-100 W/cm², ifuna imathiriyeli egcina ukusebenza ukusuka ku--40℃ukuya kwi-125℃. I-semiconductors esekwe kwi-silicon ibonisa uzinzo olubalaseleyo lwendalo, kunye nepropathi encinci yokuqhutywa kulo lonke uluhlu.

Izixhobo ze-elektroniki zijongene neemeko ezinzima nangakumbi. Ii-IGBT kunye nee-MOSFET kwizithuthi zombane kufuneka zisebenze ngokuthembekileyo kumaqondo obushushu ahlanganayo afikelela kwi-175 degree. Izinto zokupakisha ezikumgangatho ophezulu kunye ne-coefficients yobushushu engaphantsi kwe-50 ppm / idigri ziqinisekisa ukuba iimpawu zombane zihlala ngaphakathi kwenkcazo ngaphandle kokutshintsha kwe-thermal.

Ukungazinzi kobushushu kwi-electronics kubonakalisa njengeparameter drift, ukunyuka kokuvuza kwangoku, kunye neempazamo zexesha. Ukunyuka kweqondo lokushisa kwe-10 kunokuphinda kabini ukuvuza kwe-semiconductor yangoku, okuchaphazela ukusetyenziswa kwamandla kwaye kunokubangela ukungasebenzi kwesekethe. Iisistim zolawulo lwe-thermal ezisebenzisa izixhobo zokutshintsha isigaba ngoku zigcina uzinzo ngaphakathi kwe-±2 idigri naphantsi komthwalo oguqukayo womsebenzi.

Ibhetri ye-lithium ion imele obunye bobona bushushu{0}}obona buchule bogcino lwamandla. Ezi bhetri zisebenza ngokufanelekileyo phakathi kwe-15 kunye ne-35 degree, kunye nokusebenza okuthotywayo ngokukhawuleza ngaphandle kwale festile. Uzinzo lobushushu buchaphazela ngokuthe ngqo umthamo webhetri, ubomi bomjikelezo, kunye nokhuseleko.

Kubushushu obuphantsi obungaphantsi kwe-0 degree, i-electrolyte yebhetri ye-lithium ion iba yi-viscous, inciphisa kakhulu i-ionic conductivity. Umthamo unokuhla nge 30% okanye ngaphezulu kwi -20℃. Okubaluleke ngakumbi, ukutshaja kumaqondo omkhenkce emngciphekweni we-lithium plating-metallic lithium idiphozithi kwi-anode enciphisa ngokusisigxina umthamo kwaye inokubangela iisekethe ezimfutshane zangaphakathi.

Amaqondo obushushu aphezulu ngaphezu kwe-45℃akhawulezisa iindlela zokuthotywa kweebhetri ze-lithium ion. Kulo lonke unyuso lwe-10℃ngaphaya koluhlu olufanelekileyo, ubomi bomjikelezo buyancipha nge-50%. Kwi-degree ye-60 nangaphezulu, ukubola kwe-electrolyte kukhawuleza, ukuvelisa igesi eyandisa uxinzelelo lweeseli. Ukubaleka kweThermal{7}}impendulo ye-exothermic engalawulekiyo{8}}iba ngumngcipheko omkhulu ngaphezu kwe-80 degree.

Iisistim zolawulo lwebhetri ezikwinqanaba eliphezulu zijonga ubushushu beeseli ngokuchaneka kwe ±1℃, ukupholisa okusebenzayo okanye ukufudumeza ukugcina ifestile yokusebenza eyamkelekileyo. I-architecture yolawulo lwe-thermal ye-Tesla, umzekelo, isebenzisa i-glycol yokupholisa iilophu ukugcina iipakethi zebhetri ngaphakathi kwe-5 iqondo lokushisa ekujoliswe kulo ngexesha lokutshaja kunye nokukhupha.

Izixhobo zenqwelomoya zinyamezela ukuguquguquka okugqithisileyo kwamaqondo obushushu, ukusuka -idigri engama-55 kumphakamo wokuhamba ngenqanawa ukuya kuma-200℃+ kufutshane neenjini. Ingxubevange ye-Titanium kunye ne-nickel{5}esekelwe kwi-superalloys zisebenza kwindawo{8}}eziphezulu zobushushu ngenxa yokukwazi ukugcina iimpawu zomatshini ezingaphezu kwama-600 degree. Ezi zixhobo zivavanywa ngokungqongqo ngokwemigangatho ye-AEC-Q100, ziqinisekisa uzinzo nge-1,{11}} imijikelo ye-thermal.

Imathiriyeli edityanisiweyo kwiifreyim zomoya kufuneka igcine uzinzo lwe-dimensional kwimvulophu yokubhabha. Iicomposites zeCarbon fibre epoxy zibonisa ulwandiso lwe-thermal coefficients lwe-0.5-2 ppm/degree parallel to fibres-50 amaxesha ngaphantsi kwe-aluminiyam. Oku kuzinza kuthintela ukuphazamiseka kwe-thermal kunokuchaphazela i-aerodynamics okanye ukunyaniseka kwesakhiwo.

Ii-reactors zeMichiza zihlala zisebenza kumaqondo obushushu aphezulu apho uzinzo lwe-thermal lumisela ukhuseleko lwenkqubo. Iimpendulo ze-exothermic zifuna izixhobo ezimelana nokubola phantsi kweemeko eziqhelekileyo kunye neemeko eziphazamisayo. Uvavanyo lozinzo lwe-Thermal luchonga ubushushu bokusebenza obuphezulu obukhuselekileyo kwaye lubonelela ngedatha yoyilo lwenkqubo yokunceda.

Ubushushu bokudlulisa ubushushu obujikeleza kwiinkqubo zoshishino kufuneka buxhathise ukuqhekeka kwe-thermal. Ulwelo lokwenziwa kwale mihla luhlala luzinzile ukuya kuthi ga kwi-350℃+, xa kuthelekiswa ne-250℃kwi-oyile yeminerali eqhelekileyo. Olu luhlu olwandisiweyo luvumela ukuhanjiswa kobushushu okusebenzayo ngakumbi kunye nokunciphisa ukugcinwa rhoqo.

Ukuthotywa kwezinto ukusuka kuzinzo olungonelanga lobushushu kubonakalisa kwiindlela ezininzi zokusilela. Ukubola kwe-thermal kuvelisa i-byproducts eguquguqukayo eguqula ukubunjwa kweekhemikhali kunye nokudala i-voids kwizinto eziqinileyo. Ezi ziphene zesakhiwo zisasazeka, ekugqibeleni zibangele ukusilela komatshini.

Kwiipolymers, i-chain scission inciphisa ubunzima beemolekyuli, iyancipha amandla okuqina kunye nokwandisa ukuqina. Uphononongo lwe-2024 lulandele ukuthotywa kwe-polyethylene kwi-120 degree, ukujonga i-40% yokulahlekelwa kwamandla emva kweeyure ze-500. I-oxidation iyenza mandundu le nkqubo, yenze amaqela e-carbonyl aqhubela phambili ukuwohloka.

Ukungazinzi komgangatho kubangela iingxaki ezibalulekileyo kwizicelo ezichanekileyo. Amacandelo e-Optical afumana ukwanda kwe-thermal ngaphaya kokunyamezela ukuyila alahlekelwa ingqwalasela okanye ukulungelelaniswa. I-1 ppm/ idigri yomlinganiso wokwandiswa kwe-thermal iguqulela kwi-10 μm yotshintsho lwe-dimensional ngemitha nganye ye-10℃degree swing{5}}eyanele ukuthomalalisa iinkqubo ezininzi ezichanekileyo{6}}ezichanekileyo.

Ukungaphumeleli kwe-Electronic ukusuka ekungazinzi kwe-thermal kubandakanya iimpazamo zexesha, iingxaki zengqibelelo yomqondiso, kunye nomonakalo ongunaphakade. Amalungu e-Solder afumana ibhayisekile ephinda-phindiweyo yobushushu aphuhlisa iintanda zokudinwa, okonyusa ukunganyangeki kombane kude kuvuleke{1}}ukusilela kwesekethi. Uphononongo lubonisa ubomi obudityanisiweyo be-solder bulandela ubudlelwane be-Coffin{3}} noManson, kunye nemijikelo yokungaphumeleli ngokuphambanayo ngokuhambelana noxinzelelo lwe-thermal amplitude.

Iingozi zokhuseleko zivela xa imida yozinzo lwe-thermal igqithisiwe. Ukubaleka okuphumayo kwiinkqubo zemichiza kunokubangela uqhushumbo. Ibhetri ye-thermal runaway ivelisa amaqondo obushushu angaphezu kwe-800 degree, kunye nokuveliswa kwegesi enokutsha. Ulawulo olufanelekileyo lwe-thermal olusekelwe kwidatha yozinzo oluchanekileyo luthintela ukungaphumeleli okunjalo kwentlekele.

Iimpembelelo zoqoqosho zozinzo olungonelanga lobushushu ziquka ukucuthwa kobomi besixhobo, ukonyuka kweendleko zokulondolozwa, kunye nelahleko yemveliso. Izibonelelo ezisebenza kufutshane nemathiriyeli yomlinganiselo we-thermal amava okuguga okukhawulezileyo, okunokufuna ukutshintshwa kwecandelo iminyaka ngaphambi kobomi boyilo. Ishishini leoli kunye negesi liqikelela ukuba ukuzinza kwe-thermal kwi-drilling fluids kunokunciphisa iindleko zokunciphisa ixesha le-500M + ngonyaka.

Temperature Stability

Ii-electronics zabathengi zikholisa ukusebenza ngokukhuselekileyo phakathi kwe - 0 kunye ne 45℃, nangona amaqondo obushushu ogcino anokwandiswa ukusuka ku - 20℃ukuya kwi 60℃. Ii-elektroniki zemizi-mveliso kunye neemoto zifuna uluhlu olubanzi, rhoqo -40 idigri ukuya kwi-85℃ukuze isebenze kunye ne-55℃ukuya kwi-125℃yokugcina. Ii-elektroniki ezikhethekileyo zobushushu obuphezulu kwi-aerospace okanye kwi-downhole applications zinokusebenza ngokuthembekileyo ngaphezulu kwe-200℃usebenzisa i-silicon carbide semiconductors kunye nokupakishwa kwe-ceramic.

Amaqhinga amaninzi aphucula ukuzinza kwe-thermal. Ukwandisa ubuninzi be-crosslink kwiipolymers kuthintela intshukumo ye-molekyuli kwaye iphakamisa amaqondo obushushu okubola. Ukongeza izihluzi ezizinzile ngokwe-thermal njengamasuntswana e-ceramic kuphucula ukumelana nobushushu bezinto ezidibeneyo. Ukuguqulwa kweekhemikhali ezinjengokufaka imisesane enevumba elimnandi okanye amaqela afakwe i-fluorinated kwandisa amandla ebhondi. Kwizinyithi, i-alloying elements zenza iileya ze-oxide ezizinzile ezikhusela kwi-oxidation kumaqondo aphezulu. Ubuchwephesha bokugquma busebenzisa iileya ezinqabileyo ezikhuselayo ezandisa uluhlu olusebenzayo lwezixhobo ezisisiseko.

Ewe, ukuwohloka kobushushu kudla ngokubangela iinguqulelo ezingenakuguqulwa. Ukugqithisa amaqondo okushisa abalulekileyo kunokubangela ukubola kweekhemikhali, ukuguqulwa kwesigaba, okanye utshintsho lwe-microstructural oluguqula ngokusisigxina izinto eziphathekayo. Nangona kunjalo, izixhobo ezifumana iziphumo zomzimba kuphela ezifana nokwanda kwe-thermal zihlala zibuyela xa ubushushu buqhelekile. Umahluko ulele ekubeni iibhondi zeekhemikhali ziyaphuka ngexesha lokufudumeza. Emva kokuba iimolekyuli zibola, ukubuyela kubushushu obuphantsi akunakuwubuyisa umonakalo.

I-aerospace kunye nezicelo zokhuselo zifuna uzinzo olukhethekileyo lobushushu, kunye nezixhobo ezisebenza kuwo wonke amaqondo angama-250 + obushushu. Ishishini le-oyile kunye negesi lifuna uzinzo kwiindawo eziphantsi kwe-downhole ezidlula i-200℃kuxinzelelo olungaphezulu kwe-25,000 psi. Ukuveliswa kwamandla enyukliya kusebenzisa imathiriyeli ezinzileyo ukuya kuma-500℃+ kangangexesha elongeziweyo. Iinkqubo zokwenziwa eziphucukileyo ezifana nokubekwa komphunga wekhemikhali kusebenza kwi-1,000℃+, ifuna i-substrates kunye nezixhobo ezinozinzo olugqithisileyo lobushushu. Ukusetyenziswa kwesithuba sijongana nobona mbaxa babanzi, ukusuka -270℃kwisithunzi ukuya +120 isidanga kwilanga elithe ngqo.

Uzinzo lweqondo lobushushu kuthintela ngokusisiseko indawo kunye nendlela imathiriyeli enokusasazwa ngayo. Ukuqonda izinto ezichaphazela ukuziphatha kwe-thermal{1}}ukusuka kwi-molecular bonding ukuya kwiimeko zokusingqongileyo{2}} kwenza ukuba iinjineli zikhethe izixhobo ezifanelekileyo kwaye ziyile iinkqubo zolawulo olusebenzayo lwe-thermal. Njengoko izicelo zityhalela kuxinaniso lwamandla aphezulu kunye neemekobume ezirhabaxa, ukuqhubela phambili kwiqondo lobushushu{4}izinto ezizinzileyo kunye nobuchule bokulinganisa buqhubeleka nokwandisa oko kunokwenzeka ngokobuchule.

Ukudityaniswa kozinzo lwe-thermal kunye nezinye izinto eziphathekayo zenza i-tradeoffs yoyilo olunzima. Isixhobo sinokunika uzinzo oluncomekayo lobushushu kodwa amandla angasebenziyo omatshini, okanye ngokuphambeneyo. Impumelelo ifuna ukulungelelanisa iimfuno ezininzi ngelixa ihlonipha imiqobo esisiseko ebekwe yi-thermal physics.