(1) Halayen gyaran ƙarfe matsalolin da ke tattare da gyaran ƙarfe na graphite da lu'u-lu'u suna kama da waɗanda aka fuskanta a gyaran ƙarfe na yumbu. Idan aka kwatanta da ƙarfe, solder yana da wahalar jika kayan polycrystalline na graphite da lu'u-lu'u, kuma yawan faɗaɗa zafi ya bambanta sosai da na kayan gini na gabaɗaya. Ana dumama su biyu kai tsaye a cikin iska, kuma iskar oxygen ko carbonization zai faru lokacin da zafin ya wuce 400 ℃. Saboda haka, ya kamata a ɗauki gyaran ƙarfe na vacuum, kuma matakin injin ba zai zama ƙasa da 10-1pa ba. Saboda ƙarfin duka biyun ba shi da yawa, idan akwai damuwa ta zafi yayin gyaran ƙarfe, fasa na iya faruwa. Yi ƙoƙarin zaɓar ƙarfe mai cike da ƙarfe tare da ƙarancin haɓakar zafi kuma a kula da ƙimar sanyaya sosai. Tunda saman irin waɗannan kayan ba shi da sauƙi a jika su da ƙarfen cikawa na yau da kullun, ana iya sanya wani Layer na W, Mo, mai kauri 2.5 ~ 12.5um a saman kayan polycrystalline na graphite da lu'u-lu'u ta hanyar gyaran saman (rufin vacuum, sputtering ion, fesa plasma da sauran hanyoyi) kafin a yi amfani da su wajen yin amfani da carbide masu dacewa, ko kuma a yi amfani da ƙarfe masu cikawa masu aiki sosai.
Graphite da lu'u-lu'u suna da maki da yawa, waɗanda suka bambanta a girman barbashi, yawa, tsarki da sauran fannoni, kuma suna da halaye daban-daban na brazing. Bugu da ƙari, idan zafin kayan lu'u-lu'u na polycrystalline ya wuce 1000 ℃, rabon lalacewa na polycrystalline ya fara raguwa, kuma rabon lalacewa ya ragu da fiye da 50% lokacin da zafin ya wuce 1200 ℃. Saboda haka, lokacin da lu'u-lu'u na brazing na vacuum, dole ne a sarrafa zafin brazing a ƙasa da 1200 ℃, kuma matakin vacuum bai kamata ya zama ƙasa da 5 × 10-2Pa ba.
(2) Zaɓin ƙarfen cikawa na brazing ya dogara ne akan amfani da kuma sarrafa saman. Lokacin amfani da shi azaman kayan da ke jure zafi, za a zaɓi ƙarfen cikawa na brazing mai yawan zafin brazing da kuma kyakkyawan juriyar zafi; Don kayan da ke jure lalata sinadarai, ana zaɓar ƙarfen cikawa na brazing mai ƙarancin zafin brazing da kuma kyakkyawan juriyar tsatsa. Don maganin ƙarfe na graphite bayan an yi amfani da shi, ana iya amfani da ƙarfen jan ƙarfe mai tsabta tare da babban juriya da kuma kyakkyawan juriyar tsatsa. Mai aiki na jan ƙarfe mai tushen azurfa da na jan ƙarfe suna da kyakkyawan juriya da ruwa zuwa graphite da lu'u-lu'u, amma zafin sabis na haɗin gwiwa yana da wuya ya wuce 400 ℃. Don kayan aikin graphite da kayan aikin lu'u-lu'u da ake amfani da su tsakanin 400 ℃ da 800 ℃, galibi ana amfani da ƙarfen cikawa na zinariya, tushen palladium, tushen manganese ko ƙarfen cikawa na titanium. Don haɗin da ake amfani da su tsakanin 800 ℃ da 1000 ℃, za a yi amfani da ƙarfen cikawa na nickel ko na haƙa. Idan aka yi amfani da abubuwan da ke cikin graphite sama da digiri 1000, ana iya amfani da ƙarfe masu cike ƙarfe masu tsabta (Ni, PD, Ti) ko ƙarfe masu cike ƙarfe masu ɗauke da molybdenum, Mo, Ta da sauran abubuwan da za su iya samar da carbide tare da carbon.
Ga graphite ko lu'u-lu'u ba tare da maganin saman ba, ana iya amfani da ƙarfe masu aiki a cikin tebur na 16 don yin brazing kai tsaye. Yawancin waɗannan ƙarfe masu cikawa an yi su ne da ƙarfe biyu ko ƙarfe masu ƙarfi bisa titanium. Tsarkakken titanium yana amsawa da ƙarfi da graphite, wanda zai iya samar da kauri mai kauri sosai, kuma ma'aunin faɗaɗa layinsa ya bambanta da na graphite, wanda yake da sauƙin samar da tsagewa, don haka ba za a iya amfani da shi azaman solder ba. Ƙara Cr da Ni zuwa Ti na iya rage wurin narkewa da inganta danshi da yumbu. Ti ƙarfe ne mai ƙarfi, wanda galibi ya ƙunshi Ti Zr, tare da ƙara TA, Nb da sauran abubuwa. Yana da ƙarancin ma'aunin faɗaɗa layi, wanda zai iya rage damuwa ta brazing. Aluminum mai ƙarfi wanda aka haɗa shi da Ti Cu ya dace da brazing na graphite da ƙarfe, kuma haɗin yana da juriya mai ƙarfi ga lalata.
Tebur 16 ƙarfe masu cika ƙarfe don yin brazing kai tsaye na graphite da lu'u-lu'u
(3) Tsarin gyaran gashi za a iya raba hanyoyin gyaran gashi na graphite zuwa rukuni biyu, ɗaya shine gyaran gashi bayan gyaran gashi, ɗayan kuma shine gyaran gashi ba tare da maganin saman ba. Ko da wace hanya aka yi amfani da ita, za a yi wa walda kafin a haɗa ta, kuma za a goge gurɓatattun kayan graphite da barasa ko acetone. Idan ana yin gyaran gashi na saman, za a shafa Layer na Ni, Cu ko Layer na Ti, Zr ko molybdenum disilicide a saman graphite ta hanyar fesawa ta plasma, sannan a yi amfani da ƙarfe mai cike da tagulla ko ƙarfe mai cike da azurfa don gyaran gashi. Gyara kai tsaye tare da mai aiki shine hanyar da aka fi amfani da ita a yanzu. Za a iya zaɓar zafin jiki na gyaran gashi bisa ga mai haɗawa da aka bayar a tebur na 16. Ana iya ɗaure mai haɗawa a tsakiyar haɗin gwiwa ko kusa da ƙarshen ɗaya. Lokacin yin gyaran gashi da ƙarfe mai babban adadin faɗaɗa zafi, ana iya amfani da Mo ko Ti mai wani kauri azaman matsakaicin layin buffer. Tsarin canzawa zai iya haifar da lalacewar filastik yayin dumama gashi, sha damuwa ta zafi kuma ya guji fashewa ta graphite. Misali, ana amfani da Mo a matsayin haɗin canzawa don yin amfani da injin graphite da hastelloyn. Ana amfani da na'urar solder ta B-pd60ni35cr5 mai juriya ga tsatsa da kuma radiation na gishirin da aka narke. Zafin aikin na'urar shine 1260 ℃ kuma ana ajiye zafin na tsawon minti 10.
Ana iya yin amfani da lu'u-lu'u na halitta kai tsaye da b-ag68.8cu16.7ti4.5, b-ag66cu26ti8 da sauran solders masu aiki. Za a yi amfani da brazing ɗin a ƙarƙashin injin tsabtacewa ko ƙarancin kariyar argon. Ya kamata zafin brazing ɗin bai wuce 850 ℃ ba, kuma ya kamata a zaɓi saurin dumama. Lokacin riƙewa a zafin brazing bai kamata ya yi tsayi da yawa ba (galibi kimanin 10s) don guje wa samuwar layin tic mai ci gaba a mahaɗin. Lokacin brazing lu'u-lu'u da ƙarfe mai ƙarfe, ya kamata a ƙara layin filastik ko ƙaramin layin ƙarfe mai faɗaɗa don sauyawa don hana lalacewar ƙwayoyin lu'u-lu'u da matsin lamba mai yawa ke haifarwa. Kayan aikin juyawa ko kayan aikin ban sha'awa don injinan ultra-precision ana ƙera su ta hanyar tsarin brazing, wanda ke ƙarfafa ƙaramin lu'u-lu'u 20 ~ 100mg akan jikin ƙarfe, kuma ƙarfin haɗin haɗin brazing ɗin ya kai 200 ~ 250mpa
Ana iya yin amfani da lu'u-lu'u mai siffar polycrystalline ta hanyar harshen wuta, mita mai tsayi ko injin tsabtace ruwa. Za a yi amfani da ƙarfin ƙarfe mai tsayi ko na harshen wuta don yanke ƙarfe mai zagaye na saw ko dutse. Za a zaɓi ƙarfe mai aiki na Ag Cu Ti mai ƙarancin narkewa. Za a sarrafa zafin saw ɗin ƙasa da 850 ℃, lokacin dumama ba zai yi tsayi ba, kuma za a yi amfani da saurin sanyaya a hankali. Ƙananan lu'u-lu'u na polycrystalline da ake amfani da su a haƙa mai da ƙasa ba su da mummunan yanayin aiki kuma suna ɗauke da manyan nauyin tasiri. Ana iya zaɓar ƙarfe mai siffar nickel kuma ana iya amfani da foil ɗin jan ƙarfe mai tsabta azaman Layer mai haɗaka don saw ɗin injin tsabtace ruwa. Misali, ana haɗa capsules 350 ~ 400 Ф 4.5 ~ 4.5mm na lu'u-lu'u mai siffar polycrystalline a cikin ramukan ƙarfe 35CrMo ko 40CrNiMo don samar da haƙoran yankewa. Ana amfani da injin ƙarfafawa na injin, kuma matakin injin ba ya ƙasa da 5 × 10-2Pa, zafin injin ƙarfafawa shine 1020 ± 5 ℃, lokacin riƙewa shine 20 ± 2 min, kuma ƙarfin yankewar haɗin gwiwar ƙarfafawa ya fi 200mpa
A lokacin yin amfani da injin ƙarfafawa, za a yi amfani da nauyin walda don haɗawa da sanya shi gwargwadon iyawa don sanya ɓangaren ƙarfe ya danna graphite ko polycrystalline a saman ɓangaren. Lokacin amfani da injin don sanyawa, kayan haɗin dole ne su zama kayan da ke da ma'aunin faɗaɗa zafi iri ɗaya da na walda.
Lokacin Saƙo: Yuni-13-2022