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Chigawo chamkati cha chotengera chopanikizika ndi ulusi ndi kapangidwe ka mkati, komwe ntchito yake yayikulu ndikugwira ntchito ngati chotchinga chotseka kuti mpweya wopanikizika kwambiri kapena madzi osungidwa mkati mwake asatuluke, komanso kuteteza chiwalo chakunja cha ulusi. Chigawochi sichimawonongeka ndi zinthu zomwe zili mkati mwake, ndipo chiwalo chakunja ndi chiwalo cholimbikitsidwa ndi ulusi, chomwe chimagwiritsidwa ntchito kwambiri kunyamula katundu wambiri wopanikizika mkati mwa chotengera chopanikizika.

Kapangidwe ka chotengera chopanikizika cha bala la ulusi: Zotengera zokakamiza zopangidwa ndi zinthu zosiyanasiyana zimapezeka m'njira zinayi: zozungulira, zozungulira, zozungulira, ndi zozungulira. Chotengera chozungulira chimakhala ndi gawo lozungulira ndi mitu iwiri. Zotengera zokakamiza zachitsulo zimapangidwa m'mawonekedwe osavuta, ndi mphamvu zochulukirapo zosungira mbali ya axial. Pansi pa kupsinjika kwamkati, kupsinjika kwakutali ndi latitudinal kwa chotengera chozungulira ndi kofanana, ndipo ndi theka la kupsinjika kozungulira kwa chotengera chozungulira. Zipangizo zachitsulo zimakhala ndi mphamvu zofanana mbali zonse; chifukwa chake, zotengera zachitsulo zozungulira zimapangidwa kuti zikhale ndi mphamvu yofanana ndipo zimakhala ndi kulemera kochepa kwa voliyumu ndi kupsinjika komwe kwaperekedwa. Mkhalidwe wopsinjika wa chotengera chozungulira ndi wabwino, ndipo khoma la chotengera likhoza kupangidwa kukhala lopyapyala kwambiri. Komabe, chifukwa cha zovuta kwambiri popanga zotengera zozungulira, nthawi zambiri zimagwiritsidwa ntchito pazinthu zapadera monga zombo zamlengalenga. Zombo zooneka ngati mphete ndizosowa kwambiri popanga mafakitale, koma kapangidwe kake kamakhala kofunikirabe m'mikhalidwe ina yake. Mwachitsanzo, zombo zamlengalenga zimagwiritsa ntchito kapangidwe kapaderaka kuti zigwiritse ntchito mokwanira malo ochepa. Zombo zozungulira zimagwiritsidwa ntchito kwambiri kuti zigwiritse ntchito bwino malo pamene malo ndi ochepa, monga magalimoto ozungulira a tanki yamagalimoto ndi magalimoto onyamula sitima. Mabotolo amenewa nthawi zambiri amakhala ndi mphamvu zochepa kapena mphamvu zoyendera mpweya, ndipo kulemera kopepuka ndi komwe kumakondedwa.

Kuvuta kwa kapangidwe ka chotengera cha kupanikizika kwa zinthu zophatikizika, kusintha kwadzidzidzi kwa zipewa zomaliza ndi makulidwe awo, komanso makulidwe ndi ngodya yosinthasintha ya zipewa zomaliza kumabweretsa zovuta zambiri pakupanga, kusanthula, kuwerengera, ndi kupanga. Nthawi zina, zotengera za kupanikizika kwa zinthu zophatikizika sizimangofunika kuzunguliridwa pamakona osiyanasiyana ndi ma speed ratios m'zipewa zomaliza, komanso zimafuna njira zosiyanasiyana zozunguliridwa kutengera kapangidwe kake. Nthawi yomweyo, mphamvu ya zinthu zothandiza monga coefficient of friction iyenera kuganiziridwa. Chifukwa chake, kapangidwe kolondola komanso koyenera kokha ndi komwe kungatsogolere bwino njira yopangira kuzunguliridwa kwazinthu zopangidwa ndi zinthu zosiyanasiyanazotengera zopanikizika, motero zimapanga zinthu zopepuka zopangidwa ndi zotengera zopanikizika zomwe zimakwaniritsa zofunikira pa kapangidwe kake.

Zipangizo Zogwiritsira Ntchito Ziwiya Zopondereza ndi Ulusi

Chingwe cholumikizira ulusi, monga gawo lalikulu lonyamula katundu, chiyenera kukhala ndi mphamvu zambiri, modulus yapamwamba, kuchepa kwa kachulukidwe, kukhazikika kwa kutentha, kunyowa bwino kwa resin, kusinthasintha bwino, komanso kulimba kwa ulusi wofanana. Zipangizo zolimbikitsira ulusi zomwe zimagwiritsidwa ntchito kwambiri pazitseko zopepuka zophatikizira zimaphatikizapo ulusi wa kaboni, ulusi wa PBO, ulusi wa aramid, ndi ulusi wa polyethylene wolemera kwambiri.

Ulusi wa kabonindi kaboni wopangidwa ndi ulusi womwe gawo lake lalikulu ndi kaboni. Umapangidwa ndi zinthu zoyambira ulusi wachilengedwe zomwe zimapangitsa kuti mpweya ukhale woipa kutentha kwambiri ndipo ndi ulusi wopangidwa ndi ulusi wochita bwino kwambiri wokhala ndi mpweya woposa 95%. Ulusi wa kaboni uli ndi makhalidwe abwino kwambiri, ndipo kafukufuku wake unayamba zaka zoposa 100 zapitazo. Ndi ulusi wopangidwa ndi ulusi wochita bwino kwambiri, wopangidwa ndi modulus, komanso wochepa, womwe umadziwika ndi izi:

1. Kulemera kochepa komanso kopepuka. Kulemera kwa ulusi wa kaboni ndi 1.7~2 g/cm³, kofanana ndi 1/4 ya kukhuthala kwa chitsulo ndi 1/2 ya kukhuthala kwa aluminiyamu.

2. Mphamvu yayikulu komanso modulus yayikulu: Mphamvu yake ndi yayikulu nthawi 4-5 kuposa chitsulo, ndipo modulus yake yotanuka ndi yayikulu nthawi 5-6 kuposa aluminiyamu, zomwe zikuwonetsa kuchira kwathunthu kwa elasticity (Zhang Eryong ndi Sun Yan, 2020). Mphamvu yokoka ndi modulus yotanuka ya ulusi wa kaboni imatha kufika 3500-6300 MPa ndi 230-700 GPa, motsatana.

3. Kuchuluka kwa kutentha kokwanira: Kuchuluka kwa mpweya wa kaboni kumachepa ndi kutentha kowonjezereka, zomwe zimapangitsa kuti isagwe kuzizira ndi kutentha mwachangu. Sidzasweka ngakhale itazizira kuchokera madigiri zikwi zingapo Celsius mpaka kutentha kwa chipinda, ndipo sidzasungunuka kapena kufewa mumlengalenga wopanda okosijeni pa 3000℃; sidzasweka pa kutentha kwa madzi.

4. Kukana dzimbiri: Ulusi wa kaboni sugwira ntchito bwino ndi ma asidi ndipo umatha kupirira ma asidi amphamvu monga hydrochloric acid ndi sulfuric acid. Kuphatikiza apo, ma composites a ulusi wa kaboni ali ndi makhalidwe monga kukana ma radiation, kukhazikika kwa mankhwala, kuthekera koyamwa mpweya wa poizoni, komanso kuchepetsa ma neutron, zomwe zimapangitsa kuti zigwiritsidwe ntchito kwambiri mumlengalenga, usilikali, ndi madera ena ambiri.

Aramid, ulusi wachilengedwe wopangidwa kuchokera ku aromatic polyphthalamides, unayamba kumapeto kwa zaka za m'ma 1960. Kuchuluka kwake ndi kochepa kuposa ulusi wa kaboni. Ili ndi mphamvu zambiri, yokolola zambiri, yokana kukhudza bwino, yokhazikika bwino pa mankhwala, komanso yokana kutentha, ndipo mtengo wake ndi theka lokha la ulusi wa kaboni.Ulusi wa Aramidmakamaka ali ndi makhalidwe awa:

1. Kapangidwe kabwino ka makina. Ulusi wa Aramid ndi polima wosinthasintha wokhala ndi mphamvu yokoka kwambiri kuposa ma polyester wamba, thonje, ndi nayiloni. Uli ndi kutalika kwakukulu, mawonekedwe ofewa a manja, komanso kupota bwino, zomwe zimapangitsa kuti ukhale ulusi wosiyana komanso wautali.

2. Choletsa moto bwino kwambiri komanso choletsa kutentha. Aramid ili ndi mpweya wochepa woposa 28, kotero sipitiriza kuyaka ikachotsedwa pamoto. Ili ndi kutentha kokhazikika, ingagwiritsidwe ntchito nthawi zonse pa 205℃, ndipo imakhala ndi mphamvu zambiri ngakhale kutentha kopitirira 205℃. Nthawi yomweyo, ulusi wa aramid uli ndi kutentha kwakukulu, komwe kumasunga mphamvu zambiri ngakhale kutentha kopitirira 370℃.

3. Makhalidwe okhazikika a mankhwala. Ulusi wa Aramid umalimbana bwino ndi mankhwala ambiri, umatha kupirira kuchuluka kwa ma inorganic acid ambiri, komanso umalimbana bwino ndi alkali kutentha kwa chipinda.

4. Makhalidwe abwino kwambiri a makina. Ili ndi makhalidwe abwino kwambiri a makina monga mphamvu yapamwamba kwambiri, modulus yapamwamba, ndi kulemera kopepuka. Mphamvu yake ndi yowirikiza ka 5-6 kuposa waya wachitsulo, modulus yake yotanuka ndi yowirikiza ka 2-3 kuposa waya wachitsulo kapena ulusi wagalasi, kulimba kwake ndi kawiri kuposa waya wachitsulo, ndipo kulemera kwake ndi 1/5 yokha kuposa waya wachitsulo. Ulusi wa polyamide wonunkhira wakhala ukugwiritsidwa ntchito kwambiri kwa nthawi yayitali ngati ulusi wapamwamba, makamaka woyenera zombo zoyendera ndege ndi ndege zomwe zimafunikira kwambiri kuti zikhale bwino komanso mawonekedwe ake.

Ulusi wa PBO unapangidwa ku United States m'zaka za m'ma 1980 ngati chinthu cholimbikitsira zinthu zopangidwa ndi makampani opanga ndege. Ndi chimodzi mwa zinthu zabwino kwambiri za banja la polyamide zomwe zili ndi mankhwala onunkhira a heterocyclic ndipo zimadziwika kuti super fiber ya m'zaka za m'ma 2000. Ulusi wa PBO uli ndi mphamvu zabwino kwambiri zakuthupi ndi zamakemikolo; mphamvu zake, elastic modulus, komanso kukana kutentha ndi zina mwa ulusi wabwino kwambiri. Kuphatikiza apo, ulusi wa PBO uli ndi kukana kwakukulu kwa kukhudza, kukana kukwawa, komanso kukhazikika kwa mawonekedwe, ndipo ndi wopepuka komanso wosinthasintha, zomwe zimapangitsa kuti ukhale nsalu yoyenera. Ulusi wa PBO uli ndi makhalidwe akuluakulu awa:

1. Makhalidwe abwino kwambiri a makina. Zipangizo zapamwamba za ulusi wa PBO zili ndi mphamvu ya 5.8 GPa ndi modulus yotanuka ya 180 GPa, yomwe ndi yapamwamba kwambiri pakati pa ulusi wa mankhwala womwe ulipo.

2. Kukhazikika kwabwino kwambiri pa kutentha. Imatha kupirira kutentha mpaka 600℃, yokhala ndi chizindikiro chocheperako cha 68. Siyaka kapena kufooka mu lawi, ndipo kukana kutentha kwake komanso kuchedwa kwa lawi ndi kwakukulu kuposa ulusi wina uliwonse wachilengedwe.

Popeza ndi ulusi wa m'zaka za m'ma 2000 womwe umagwira ntchito bwino kwambiri, ulusi wa PBO uli ndi mphamvu zowoneka bwino, zamakanika, komanso zamakemikolo. Mphamvu zake ndi modulus yake yotanuka ndi kawiri kuposa ulusi wa aramid, ndipo ili ndi mphamvu zoteteza kutentha komanso kukana malawi ngati meta-aramid polyamide. Mphamvu zake zakuthupi ndi zamakemikolo zimaposa zonse za ulusi wa aramid. Ulusi wa PBO wa mainchesi 1mm umatha kunyamula chinthu cholemera mpaka 450kg, ndipo mphamvu zake ndi zoposa nthawi 10 kuposa ulusi wachitsulo.

Ulusi wa polyethylene wolemera kwambiri wa molekyulu, yomwe imadziwikanso kuti ulusi wa polyethylene wamphamvu kwambiri, wokhala ndi modulus yapamwamba, ndi ulusi wokhala ndi mphamvu zapadera kwambiri komanso modulus yeniyeni padziko lonse lapansi. Ndi ulusi wopangidwa kuchokera ku polyethylene wokhala ndi kulemera kwa mamolekyulu kuyambira 1 miliyoni mpaka 5 miliyoni. Ulusi wa polyethylene wolemera kwambiri uli ndi makhalidwe awa:

1. Mphamvu yeniyeni yeniyeni ndi modulus yeniyeni yeniyeni. Mphamvu yake yeniyeni ndi yoposa nthawi khumi kuposa waya wachitsulo wa gawo lomwelo, ndipo modulus yake yeniyeni ndi yachiwiri kuposa ulusi wapadera wa kaboni. Kawirikawiri, kulemera kwake kwa mamolekyulu kumakhala kopitilira 10, ndi mphamvu yolimba ya 3.5 GPa, modulus yotanuka ya 116 GPa, ndi kutalika kwa 3.4%.

2. Kuchuluka kochepa. Kuchuluka kwake nthawi zambiri kumakhala 0.97 ~ 0.98 g/cm³, zomwe zimapangitsa kuti iyandama pamadzi.

3. Kutalikirana pang'ono panthawi yopuma. Ili ndi mphamvu yoyamwa mphamvu zambiri, kukana kukhudza ndi kudula bwino, kukana nyengo bwino, komanso kukana kuwala kwa ultraviolet, ma neutron, ndi ma gamma rays. Ilinso ndi mphamvu yoyamwa mphamvu zambiri, kukana kwa dielectric kochepa, kutumizira mafunde amphamvu kwambiri, komanso kukana dzimbiri la mankhwala, komanso kukana kuwonongeka kwa nthawi yayitali komanso kusinthasintha kwa nthawi yayitali.

Ulusi wa polyethylene uli ndi mphamvu zambiri, zomwe zimasonyeza ubwino waukulu mu kapangidwe kake.ulusi wochita bwino kwambirimsika. Kuyambira mizere yomangira m'minda yamafuta ya m'mphepete mwa nyanja mpaka zinthu zopepuka zophatikizika bwino, ikuwonetsa zabwino zazikulu pankhondo zamakono, komanso m'magawo a ndege, ndege, ndi nyanja, ikuchita gawo lofunikira kwambiri pazida zodzitetezera ndi madera ena.