Boron carbide yana ɗaya daga cikin mafi ƙarancin kayan aikin injiniya da ake samu; lu'u-lu'u kawai da cubic boron nitride sun fi wuya. Tare da babban lanƙwasawa ƙarfi, mai kyau lalata juriya, da thermal conductivity m ga aikace-aikace kamar fashewa nozzles da famfo hatimi. Machining boron carbide yumbu na iya zama duka tsada da kuma cin lokaci saboda ta kore ko biskit jihar ba rike m tolerances da shrinkage a lokacin sintering by game. 20%.
Hanyoyin masana'antu
Boron carbide (B4C) yana daya daga cikin mafi wahalar kayan da mutum ya sani, fahariyar ƙimar taurin kwatankwacin lu'u-lu'u da kwanciyar hankali. Ana amfani dashi a aikace-aikace inda juriya mai girma, ƙarfi a ƙananan nauyi, ko kwanciyar hankali na thermal yana da mahimmanci, kamar kariyar tayal sulke na sulke na ballistic ga jami'an soji da motoci daga abubuwan fashewa, harsashi, gutsuttsura ko wasu majigi – waɗannan halayen sun sa B4C ya zama abu mai mahimmanci.
yadda ake boron carbide yumbu? A al'adance, An kera cikakkun sassan boron carbide masu yawa ta hanyar amfani da dabarun latsawa kamar matsi mai zafi ko matsi mai isostatic da kuma spark plasma sintering.; wadannan hanyoyin, duk da haka, zo da yawa drawbacks ciki har da geometric hadaddun da girman hani, buƙatun farashin kayan aiki da kuma buƙatar aiwatar da ayyukan bayan-sintering kamar injiniyoyi.
Anan ya ta'allaka ne da mahimmancin ƙirƙirar da aka kwatanta a nan: ya shafi hanyar samar da yumbun carbide boron wanda ya haɗu da fa'idodin kore, biskit, ko wani bangare na boron carbide da aka kera da yumbu mai ƙera boron carbide.
Wannan hanyar ta ƙunshi haɗaɗɗen albarkatun ƙasa masu ɗauke da amorphous B da C bangaren tare da filayen carbon nano a cikin yanayin tarwatsewa daidai., da kuma ƙaddamar da wannan cakuda zuwa haɗuwa tare da haɗin gwiwa ta amfani da hanyar SPS. Wannan yana samar da ƙaramin ƙaramin sintepon tare da babban abun ciki na B4C da ingantattun kaddarorin inji; Ana iya daidaita abubuwan da ke tattare da shi ta hanyar canza kaso na atomic na boron da carbon don halaye daban-daban.
Kayayyaki
Boron carbide B4C abu ne da aka sani da yumbu, bambanta da ƙananan yawa, high Hugoniot na roba iyaka da super-high high taurin kaddarorin. Duk da haka, yana fama da rashin haƙuri da lalacewa da ƙarfi yana iyakance aikace-aikacen sa a fagage da yawa. Don haɓaka waɗannan kaddarorin kayan aikin jiki, Masu bincike sun yi ƙoƙari su ƙara wasu abubuwan da suka haɗa da sinadarai daban-daban ciki har da oxides dangane da ƙananan karafa da kuma silicon Si mai tsabta [3,6,7] amma waɗannan na iya rage yawan zafin jiki / matsa lamba don haka suna samar da abubuwa masu yawa yayin da suke canza wasu kaddarorin na musamman waɗanda ke yin B4C na musamman.!
Kwanan nan, kayayyaki na musamman sun zama larura a cikin ci-gaba na lantarki, sararin samaniya da fasahar kwamfuta. Waɗannan suna buƙatar babban kwanciyar hankali na thermal kazalika da juriya mai kyau na abrasion – wani abu boron carbide yumbu iya gamsarwa.
boron carbide yumbu yana ɗaya daga cikin sanannun abubuwan da aka sani kuma yana da ƙarfi na musamman, sanya shi manufa don amfani a matsayin abrasive da kuma yanke karfe gami kamar titanium, aluminum da bakin karfe. Bugu da kari, Ƙarfinsa ya ba da damar yin amfani da shi don kera rigar harsashi saboda ya fi nauyi fiye da sulke na ƙarfe tare da juriya mai girma.; mafi juriya zafi fiye da aluminum kamar yadda zai iya jure yanayin zafi 1,800 digiri Celsius na tsawon lokaci ba tare da narkewa ba, yin wannan abu mai mahimmanci a cikin aikace-aikacen soja da nau'ikan yumbu masu juriya sosai waɗanda ke jure yawan damuwa fiye da aluminum na iya taɓa sarrafa shi kaɗai.! Ƙarshe boron carbide yumbura yana ba da matsananciyar dorewa da juriya mai ƙarfi tare da ƙarfi mai ƙarfi yana cikin sahun su.
Aikace-aikace
Boron carbide abu ne mai wuyar gaske, m abu iya jure high yanayin zafi yayin da mallakan babban lalacewa juriya. An yi amfani da shi a yawancin aikace-aikacen masana'antu kamar yankan, niƙa, polishing da lapping aikace-aikace; Bugu da ƙari, yana yin kyakkyawan abu mai lalata da ake amfani da shi azaman sulke akan kayan soja da motoci kamar jirage masu saukar ungulu waɗanda ke buƙatar kariya daga harsashi daga ƙasa..
Saboda tsananin taurinsa, boron carbide na iya zama da wahala sosai don haƙawa – wannan yana gabatar da matsaloli na musamman lokacin gina gine-gine tare da abubuwan yumbu waɗanda aka yi daga wannan kayan. Kayan aikin hako na'ura na al'ada ba za su iya shiga cikin shi cikin sauƙi ba; maimakon ƙwararrun ƙwararrun lu'u-lu'u na iya buƙatar a yi amfani da su maimakon aikin hakowa mai inganci.
Hanya ɗaya don magance wannan matsala ta haɗa da yin amfani da abin saka tungsten carbide don haƙa ramuka ta hanyar yumburan carbide na boron.. Abin takaici, wannan hanyar ba ta da inganci kuma tana ɗaukar lokaci; Don haka zai fi kyau a sami wata hanyar da za ta iya ba da damar shiga ciki ba tare da buƙatar canza ko cirewa da maye gurbin wannan ɓangaren tsarin ba a duk lokacin da abin da ake buƙata ya maye gurbin..
Wannan ƙirƙirar tana bayyana hanyar samar da ƙaramin yumbu na boron carbide wanda ya ƙunshi fiber nano fiber. (CNF) rarraba iri ɗaya a saman ta. An ƙirƙiri yumbura kai tsaye ta hanyar haɗawa lokaci guda tare da daidaita cakudawar B da C amorphous; Sakamako ya nuna cewa daya irin wannan m tare da 15% ta ƙarar CNF yana nuna kyawawan kayan aikin injiniya kamar ƙarfin lanƙwasa (710 MPa), Vickers taurin (364 GPA), da karaya taurin KIC (7.6 MPa*m1/2).
Amfani
Boron carbide abu ne mai wuyar gaske wanda za'a iya samar dashi zuwa siffofi daban-daban. Yana alfahari mafi girman juriya da juriya na zafin jiki, har ma ana iya amfani da shi azaman abrasive a cikin masu yankan jet na ruwa don yanke karafa da sauran kayan. Boron carbide ya kuma sami amfani a matsayin kayan sarrafawa a cikin masana'antar makamashin nukiliya saboda ikonsa na ɗaukar makamashin neutrons na thermal da kuma kasancewa maras narkewa tare da nitric acid kuma yanayin yanayin hydrogen fluoride ba ya shafa..
Ana iya samar da yumbu na boron carbide ta amfani da matakai daban-daban, gami da sintering mara matsi a babban zafin jiki (wanda aka fi sani da spark plasma sintering; SPS). Ana haxa foda na SPS tare da carbon nanofiber kuma an sanya su cikin sifofi masu yawa ta amfani da dumama wutar lantarki na yanzu.; wannan yana haifar da babban ƙarfin lanƙwasawa mai maki uku da yumbu juriya wanda ke samar da madaidaicin ma'auni uku na yumbu boron carbide abu..