(1) Brazing maitiro matambudziko anowanikwa mugraphite uye diamond polycrystalline brazing akafanana chaizvo neaya anosangana nawo mu ceramic brazing.Kana ichienzaniswa nesimbi, solder yakaoma kunyorova graphite uye diamond polycrystalline zvinhu, uye iyo coefficient yekuwedzera kwekupisa kwakasiyana zvakanyanya kubva kune yakajairika maumbirwo zvinhu.Iwo maviri anodziya zvakananga mumhepo, uye oxidation kana carbonization ichaitika kana tembiricha yadarika 400 ℃.Naizvozvo, vacuum brazing ichagamuchirwa, uye iyo vacuum degree haizove iri pasi pe10-1pa.Nokuti simba rezvose harina kukwirira, kana pane kushushikana kwekushisa panguva yebrazing, kuputika kunogona kuitika.Edza kusarudza brazing filler simbi ine yakaderera coefficient yekuwedzera kupisa uye kunyatso dzora mwero wekutonhora.Sezvo pamusoro pezvinhu zvakadaro zvisiri nyore kunyoroveswa neakajairwa brazing filler simbi, layer ye2.5 ~ 12.5um gobvu W, Mo uye zvimwe zvinhu zvinogona kuiswa pamusoro pegraphite uye diamond polycrystalline zvinhu nekugadziriswa kwepasi (vacuum coating. , ion sputtering, plasma spraying nedzimwe nzira) usati wagadzira uye kugadzira carbides inoenderana navo, kana yakakwirira basa brazing filler masimbi anogona kushandiswa.
Graphite nedhaimani zvine mamakisi akawanda, ayo akasiyana mukukura kwechidimbu, density, kuchena uye zvimwe zvinhu, uye ane akasiyana brazing maitiro.Uye zvakare, kana tembiricha ye polycrystalline diamond zvinhu zvakapfuura 1000 ℃, iyo polycrystalline kupfeka ratio inotanga kuderera, uye chiyero chekupfeka chinodzikira neinopfuura 50% kana tembiricha inopfuura 1200 ℃.Naizvozvo, kana vacuum brazing dhaimani, tembiricha yebrazing inofanira kudzorwa pazasi 1200 ℃, uye iyo vacuum degree haizove isingasviki 5 × 10-2Pa.
(2) Sarudzo yebrazing filler simbi inonyanya kuenderana nekushandiswa uye pamusoro pekugadzirisa.Kana ichishandiswa sechinhu chinodzivirira kupisa, iyo brazing filler simbi ine yakakwirira brazing tembiricha uye yakanaka kupisa inodzivirira ichasarudzwa;Kwemakemikari asingadziviriri zvinhu, brazing filler simbi ine yakaderera brazing tembiricha uye yakanaka corrosion kuramba inosarudzwa.Kune iyo graphite mushure mepamusoro metallization kurapwa, yakachena mhangura solder ine yakakwira ductility uye yakanaka corrosion kuramba inogona kushandiswa.Sirivha yakavakirwa uye mhangura yakavakirwa inoshanda solder ine yakanaka kunyorova uye fluidity kune graphite nedhaimani, asi tembiricha yebasa yebrazed joint yakaoma kudarika 400 ℃.Kune zvikamu zvegraphite uye maturusi edhaimani anoshandiswa pakati pe400 ℃ ne800 ℃, chigadziko chegoridhe, palladium base, manganese base kana titanium base filler simbi inowanzo shandiswa.Pamajoini anoshandiswa pakati pe800 ℃ ne1000 ℃, nickel based kana drill based filler metals ichashandiswa.Kana zvikamu zvegraphite zvichishandiswa pamusoro pe1000 ℃, simbi yakachena yekuzadza simbi (Ni, PD, Ti) kana alloy filler simbi dzine molybdenum, Mo, Ta uye zvimwe zvinhu zvinogona kugadzira carbides nekabhoni zvinogona kushandiswa.
Kune graphite kana dhaimani isina kurapwa kwepamusoro, iyo inoshanda yekuzadza simbi mutafura 16 inogona kushandiswa kunanga brazing.Mazhinji emasimbi aya ekuzadza titanium yakavakirwa mabhinari kana ternary alloys.Titanium yakachena inobata zvakasimba ne graphite, iyo inogona kuumba carbide layer yakakora, uye mutsara wayo wekuwedzera wakasiyana zvakasiyana kubva kune girafu, iyo iri nyore kugadzira mitswe, saka haigoni kushandiswa se solder.Kuwedzerwa kweCr uye Ni kune Ti kunogona kuderedza nzvimbo yekunyungudika uye kunatsiridza kunyorova nemakeramiki.Ti ndeye ternary alloy, inonyanya kuumbwa neTi Zr, pamwe nekuwedzera kweTA, Nb uye zvimwe zvinhu.Iyo ine yakaderera coefficient yekuwedzera kwemutsara, iyo inogona kuderedza kushushikana kwebrazing.Iyo ternary alloy inonyanya kuumbwa neTi Cu yakakodzera kubhuroka kwegraphite nesimbi, uye iyo yakabatana ine yakakwira corrosion resistance.
Tafura 16 brazing filler simbi yekunangisa brazing yegraphite nedhaimani
(3) Brazing process nzira dzekubhuroka dzegraphite dzinogona kukamurwa kuita mapoka maviri, imwe iri brazing mushure memetallization, uye imwe iri kubhuroka pasina kurapwa kwepamusoro.Hazvina mhosva kuti ndeipi nzira inoshandiswa, iyo weldment ichagadziriswa isati yasangana, uye kusvibiswa kwepamusoro kwezvinhu zvegraphite kuchaputswa nedoro kana acetone.Kana iri pamusoro pesimbi yekushongedza, dhizaini yeNi, Cu kana dhizaini yeTi, Zr kana molybdenum disilicide ichaputirwa pamusoro pegraphite nekupfapfaidza kweplasma, uye ipapo mhangura-based filler simbi kana sirivheri based filler simbi ichashandiswa kubhuroka. .Yakananga brazing ine inoshanda solder ndiyo inonyanya kushandiswa nzira panguva ino.Kupisa kwekushisa kunogona kusarudzwa maererano nemutengesi wakapiwa mutafura 16. Iyo solder inogona kusungirirwa pakati pejojo rakasungwa kana pedyo nemugumo mumwe.Paunenge uchibhuroka nesimbi ine hombe coefficient yekuwedzera kupisa, Mo kana Ti ine humwe ukobvu inogona kushandiswa seyepakati buffer layer.Iyo yekushandura layer inogona kuburitsa epurasitiki deformation panguva yekudziya kupisa, kunwisa kushushikana kwekupisa uye kudzivirira kuputika kwegraphite.Semuenzaniso, Mo inoshandiswa sechinjo yejoint yevacuum brazing yegraphite uye hastelloyn zvikamu.B-pd60ni35cr5 solder ine kumira zvakanaka kune yakanyungudutswa munyu ngura uye mwaranzi inoshandiswa.Iyo tembiricha yekubatira i1260 ℃ uye tembiricha inochengeterwa 10min.
Madhaimani echisikigo anogona kugadzirwa zvakananga ne b-ag68.8cu16.7ti4.5, b-ag66cu26ti8 uye mamwe masoja anoshanda.Iyo brazing ichaitwa pasi pevacuum kana yakaderera argon dziviriro.Iyo tembiricha yekudziya haifanirwe kudarika 850 ℃, uye inokurumidza kupisa mwero inofanira kusarudzwa.Iyo nguva yekubata pakudziya kwebrazing haifanirwe kunge yakareba (kazhinji ingangoita gumi) kudzivirira kuumbwa kweinoenderera tic layer pane iyo interface.Kana uchigadzira madhaimondi uye alloy simbi, epurasitiki interlayer kana yakaderera yekuwedzera alloy layer inofanirwa kuwedzerwa kuitira shanduko kudzivirira kukuvadzwa kwemadhaimani zviyo zvinokonzerwa nekunyanya kupisa kwekushushikana.Chishandiso chekushandura kana chishandiso chinofinha che Ultra precision machining chinogadzirwa ne brazing process, iyo brazes 20 ~ 100mg diki chidimbu dhaimondi pamutumbi wesimbi, uye kusimba kwekubatana kwejoinhi yebrazing inosvika 200 ~ 250mpa.
Polycrystalline diamond inogona kuvezwa nemurazvo, yakakwira frequency kana vacuum.High frequency brazing kana flame brazing ichagamuchirwa yedhaimani denderedzwa saha yekucheka simbi kana dombo.Ag Cu Ti inoshanda brazing yekuzadza simbi ine yakaderera nzvimbo yekunyungudika ichasarudzwa.Iyo tembiricha yebrazing ichadzorwa pasi pe850 ℃, nguva yekudziya haifanirwe kureba, uye inononoka kutonhora inogamuchirwa.Polycrystalline diamond mabits anoshandiswa mupetroleum uye geological drilling ane hurombo hwekushanda mamiriro uye anotakura mitoro mikuru.Nickel yakavakirwa brazing yekuzadza simbi inogona kusarudzwa uye yakachena foil yemhangura inogona kushandiswa seye interlayer yevacuum brazing.Semuyenzaniso, 350 ~ 400 capsules Ф 4.5 ~ 4.5mm columnar polycrystalline diamond inonamirwa mukati meiyo perforations ye35CrMo kana 40CrNiMo simbi kugadzira mazino ekucheka.Vacuum brazing inogamuchirwa, uye dhigirii yevacuum haisi pasi pe5 × 10-2Pa, kupisa kwebrazing i1020 ± 5 ℃, nguva yekubata i20 ± 2min, uye simba rekugera rejojo rekubhura rinopfuura 200mpa.
Munguva yebrazing, huremu hwehuremu hweweldment huchashandiswa kuungana uye kuisa nzvimbo zvakanyanya sezvinobvira kuita kuti chikamu chesimbi chitsikidze graphite kana polycrystalline zvinhu kumusoro.Paunenge uchishandisa gadziriso yekumisikidza, iyo yekumisikidza ichave chinhu chine thermal yekuwedzera coefficient yakafanana neyeiyo weldment.
Nguva yekutumira: Jun-13-2022