(1) Iimpawu zokubrawuza iingxaki ezibandakanyekayo kwi-graphite kunye ne-diamond polycrystalline brazing zifana kakhulu nezo zidibene ne-ceramic brazing.Xa kuthelekiswa nesinyithi, i-solder inzima ukumanzisa i-graphite kunye ne-diamond polycrystalline izinto, kwaye i-coefficient yayo yokwandiswa kwe-thermal ihluke kakhulu kwizinto zezakhiwo eziqhelekileyo.Ezi zimbini zifudunyezwa ngqo emoyeni, kwaye i-oxidation okanye i-carbonization iya kwenzeka xa ubushushu budlula i-400 ℃.Ke ngoko, i-vacuum brazing iya kwamkelwa, kwaye idigri yevacuum ayiyi kuba ngaphantsi kwe-10-1pa.Ngenxa yokuba amandla omabini akaphezulu, ukuba kukho uxinzelelo lwe-thermal ngexesha lokuqhayisa, ukuqhekeka kungenzeka.Zama ukukhetha i-brazing filler metal ene-coefficient ephantsi yokwandiswa kwe-thermal kunye nokulawula ngokungqongqo izinga lokupholisa.Ekubeni umphezulu wezinto ezinjalo akulula ukumanziswa zisinyithi eziqhelekileyo zokuzalisa i-brazing, umaleko we-2.5 ~ 12.5um ubukhulu be-W, i-Mo kunye nezinye izinto zingafakwa kumphezulu we-graphite kunye ne-diamond polycrystalline izinto ngokuguqulwa komphezulu (i-vacuum coating. , i-ion sputtering, i-plasma yokutshiza kunye nezinye iindlela) ngaphambi kokubrawuza kunye nefom ye-carbides ehambelanayo kunye nabo, okanye i-high-brazing filler metals ingasetyenziswa.
Igraphite kunye nedayimane zinamabakala amaninzi, ahluke ngobukhulu bamasuntswana, ukuxinana, ubunyulu kunye neminye imiba, kwaye ineempawu zokubrawuza ezahlukeneyo.Ukongeza, ukuba ubushushu bezinto zedayimani ze-polycrystalline zidlula i-1000 ℃, umlinganiselo wokunxiba we-polycrystalline uqala ukuncipha, kwaye umlinganiselo wokunxiba wehla ngaphezu kwe-50% xa ubushushu budlula i-1200 ℃.Ngoko ke, xa i-vacuum brazing diamond, iqondo lokushisa lokutshisa kufuneka lilawulwe ngaphantsi kwe-1200 ℃, kwaye idigri ye-vacuum ayiyi kuba ngaphantsi kwe-5 × 10-2Pa.
(2) Ukukhethwa kwesinyithi sokuzalisa i-brazing kusekelwe ikakhulu ekusebenziseni kunye nokulungiswa kwendawo.Xa isetyenziswe njengento ekwazi ukumelana nobushushu, isinyithi sokutshiza esine-brazing kunye nobushushu obuphezulu kunye nokumelana nobushushu kuya kukhethwa;Kwizinto zekhemikhali ezinganyangekiyo kwi-corrosion, iintsimbi zokuzalisa i-brazing kunye nobushushu obuphantsi bokubrawuza kunye nokumelana ne-corrosion elungileyo kukhethiwe.Kwigraphite emva konyango lwe-metalization ye-surface, i-solder yobhedu ecocekileyo ene-ductility ephezulu kunye nokuchasana kokubola kakuhle kunokusetyenziswa.I-solder esebenzayo esekelwe kwisilivere kunye nobhedu inokumanzi kakuhle kunye nokumanzi kwigraphite kunye nedayimane, kodwa ubushushu benkonzo yejoyinti yebrazed kunzima ukugqitha kuma-400 ℃.Kwizixhobo zegraphite kunye nezixhobo zedayimane ezisetyenziswa phakathi kwe-400 ℃ kunye ne-800 ℃, isiseko segolide, isiseko se-palladium, isiseko semanganese okanye isinyithi sesiseko se-titanium sihlala sisetyenziswa.Kumalungu asetyenziswa phakathi kwe-800 ℃ kunye ne-1000 ℃, i-nickel esekwe okanye i-drill based based filler metals iya kusetyenziswa.Xa amacandelo egraphite asetyenziswa ngaphezulu kwe-1000 ℃, isinyithi esisulungekileyo sokuzalisa isinyithi (Ni, PD, Ti) okanye isinyithi se-alloy filler equkethe i-molybdenum, i-Mo, i-Ta kunye nezinye izinto ezinokuthi zenze i-carbides nge-carbon zingasetyenziswa.
Kwigraphite okanye idayimane ngaphandle konyango lomphezulu, iintsimbi ezisebenzayo zokuzalisa kwitafile ye-16 zingasetyenziselwa ukunyathela ngokuthe ngqo.Uninzi lwezi zinyithi zokugcwalisa ziyi-titanium esekwe kwibinary okanye i-ternary alloys.I-titanium ecocekileyo isabela ngamandla kunye negraphite, enokuthi yenze umaleko oshinyene kakhulu we-carbide, kwaye i-coefficient yayo yokwandiswa komgca yahluke kakhulu kuleyo yegraphite, ekulula ukuvelisa iintanda, ngoko ayinakusetyenziswa njenge-solder.Ukongezwa kwe-Cr kunye ne-Ni ukuya kwi-Ti kunokunciphisa indawo yokunyibilika kunye nokuphucula ukumanzi kunye neekeramics.I-Ti yi-alloy ye-ternary, ikakhulukazi iqulunqwe nguTi Zr, kunye nokongezwa kwe-TA, i-Nb kunye nezinye izinto.Ine-coefficient ephantsi yokwandiswa komgca, oko kunokunciphisa uxinzelelo lwe-brazing.I-alloy ye-ternary ikakhulu iqulunqwe yi-Ti Cu ifanelekile ukubethelwa kwegraphite kunye nentsimbi, kwaye i-joint inokumelana nokugqwala okuphezulu.
Itheyibhile ye-16 yokuqhawula iintsimbi zokuzalisa ukubethelwa ngokuthe ngqo kwegraphite kunye nedayimane
(3) Inkqubo yokutshisa i-brazing ye-graphite inokwahlulwa ibe ngamacandelo amabini, enye i-brazing emva kwe-metallization yomhlaba, kwaye enye i-brazing ngaphandle kokunyangwa kwendawo.Kungakhathaliseki ukuba yeyiphi indlela esetyenzisiweyo, i-weldment iya kucutshungulwa ngaphambi kokuhlanganiswa, kwaye iindawo ezingcolileyo ze-graphite ziyakusulwa ngotywala okanye i-acetone.Kwimeko yokubrawuza umphezulu wesinyithi, umaleko we-Ni, Cu okanye i-Ti, iZr okanye i-molybdenum disilicide iya kucandwa kumphezulu wegraphite ngokutshiza ngeplasma, emva koko isinyithi esekwe kubhedu okanye isinyithi esekwe kwisilivere iya kusetyenziselwa ukubrawuza. .Ukuqhafaza ngokuthe ngqo nge-solder esebenzayo yeyona ndlela isetyenziswa kakhulu ngoku.Ukushisa okutshisayo kunokukhethwa ngokwe-solder ebonelelwe kwitheyibhile 16. I-solder inokunyanzeliswa phakathi kwendawo edibeneyo okanye isondele ekupheleni.Xa ubhobhoza ngesinyithi kunye ne-coefficient enkulu yokwandiswa kwe-thermal, i-Mo okanye i-Ti enobunzima obuthile ingasetyenziswa njengomaleko we-buffer ophakathi.Umaleko wenguqu unokuvelisa i-deformation yeplastiki ngexesha lokufudumala kwe-brazing, ukufunxa uxinzelelo lwe-thermal kwaye ugweme ukuqhekeka kwegraphite.Umzekelo, i-Mo isetyenziswa njengejoyinti yenguqu ye-vacuum brazing yegraphite kunye ne-hastelloyn components.I-solder ye-B-pd60ni35cr5 enokuxhathisa okulungileyo kwi-corrosion yetyuwa etyhidiweyo kunye nemitha yemitha isetyenziswa.Iqondo lobushushu lokutshisa liyi-1260 ℃ kwaye iqondo lobushushu ligcinwa kwi-10min.
Idayimani yendalo inokuxutywa ngokuthe ngqo nge-b-ag68.8cu16.7ti4.5, b-ag66cu26ti8 kunye nezinye ii-solders ezisebenzayo.Ukubethelwa kuya kwenziwa phantsi kwe-vacuum okanye ukhuseleko oluphantsi lwe-argon.Iqondo lokushisa lokutshisa akufanele lidlule i-850 ℃, kwaye izinga lokufudumeza ngokukhawuleza kufuneka likhethwe.Ixesha lokubamba kwiqondo lokushisa lokutshisa akufanele libe lide kakhulu (ngokubanzi malunga ne-10s) ukuphepha ukubunjwa kwe-tic layer eqhubekayo kwi-interface.Xa ubhobhoza idayimani kunye nentsimbi ye-alloy, i-plastic interlayer okanye i-alloy ephantsi yokwandisa i-alloy layer kufuneka yongezwe kwinguqu yokukhusela umonakalo weenkozo zedayimani ezibangelwa uxinzelelo olugqithisileyo lwe-thermal.Isixhobo sokuguqula okanye isixhobo esinesithukuthezi se-ultra precision machining senziwa yinkqubo yokuqhafaza, eyenza i-20 ~ 100mg i-diamond encinci ye-diamond kumzimba wentsimbi, kwaye amandla adibeneyo okudibanisa i-brazing afikelela kwi-200 ~ 250mpa.
Idayimani yePolycrystalline inokugqalwa ngumlilo, isantya esiphezulu okanye ivacuum.Ukubrawuza okuphezulu okanye ukubranywa kwedangatye kuya kwamkelwa ngencakuba yedayimani esetyhula yokusika isinyithi okanye ilitye.I-Ag Cu Ti esebenzayo yokuzalisa isinyithi enendawo yokunyibilika ephantsi iya kukhethwa.Iqondo lobushushu lokubrawuza liya kulawulwa ngaphantsi kwe-850 ℃, ixesha lokufudumeza aliyi kuba lide kakhulu, kwaye isantya sokupholisa esicothayo siyakwamkelwa.Amasuntswana edayimane ePolycrystalline asetyenziswa kwipetroleum kunye nokwembiwa kwejoloji aneemeko ezingentle zokusebenza kwaye athwala imithwalo enkulu yeempembelelo.I-nickel esekelwe kwi-brazing filler metal inokukhethwa kwaye i-foil yobhedu ecocekileyo ingasetyenziswa njenge-interlayer ye-vacuum brazing.Ngokomzekelo, i-350 ~ 400 capsules Ф 4.5 ~ 4.5mm columnar polycrystalline idayimane igxininiswe kwi-perforations ye-35CrMo okanye i-40CrNiMo yensimbi yokwenza amazinyo okusika.I-vacuum brazing yamkelwe, kwaye idigri ye-vacuum ayikho ngaphantsi kwe-5 × 10-2Pa, ukushisa kwe-brazing yi-1020 ± 5 ℃, ixesha lokubamba li-20 ± 2min, kwaye amandla e-shear ye-brazing joint inkulu kune-200mpa.
Ngexesha lokugcoba, ubunzima bokuzimela be-weldment buya kusetyenziselwa ukudibanisa kunye nokubeka ngokusemandleni ukwenza inxalenye yentsimbi icinezele i-graphite okanye i-polycrystalline impahla kwindawo ephezulu.Xa usebenzisa i-fixture yokubeka indawo, i-fixture material iya kuba yinto ene-coefficient yokwandisa i-thermal efana ne-weldment.
Ixesha lokuposa: Jun-13-2022