(1) Hunhu hweBrazing matambudziko anowanikwa mu graphite ne diamond polycrystalline brazing akafanana zvikuru neaya anowanikwa mu ceramic brazing. Kana tichienzanisa nesimbi, solder inonetsa kunyorovesa graphite ne diamond polycrystalline materials, uye coefficient yayo yekuwedzera kwekupisa yakasiyana zvikuru neyezvinhu zvekuvaka zvakajairika. Zvese izvi zvinopiswa zvakananga mumhepo, uye oxidation kana carbonization zvichaitika kana tembiricha yadarika 400 ℃. Saka, vacuum brazing inofanira kushandiswa, uye vacuum degree haifanirwe kunge iri pasi pe 10-1pa. Nekuti simba rezvose zviri zviviri harisi rakakwirira, kana paine thermal stress panguva yebrazing, cracks dzinogona kuitika. Edza kusarudza brazing filler simbi ine coefficient yakaderera yekuwedzera kwekupisa uye dzora zvakanyanya kutonhora. Sezvo pamusoro pezvinhu zvakadaro zvisiri nyore kunyoroveswa nesimbi dzakajairika dzebrazing filler, jira rine ukobvu hwe2.5 ~ 12.5um W, Mo nezvimwe zvinhu zvinogona kuiswa pamusoro pezvinhu zvegraphite nediamond polycrystalline nekuchinja pamusoro (vacuum coating, ion sputtering, plasma spraying nedzimwe nzira) usati waisa brazing uye kugadzira macarbides anoenderana nazvo, kana simbi dzebrazing filler dzinoshanda zvakanyanya dzinogona kushandiswa.
Graphite nedhaimani zvine magiredhi akawanda, ayo akasiyana muhukuru hwezvidimbu, huwandu, kuchena nezvimwe zvinhu, uye ane hunhu hwakasiyana hwekushongedza. Pamusoro pezvo, kana tembiricha yezvinhu zvemadhaimani zvepolycrystalline ikadarika 1000 ℃, chiyero chekupfeka chepolycrystalline chinotanga kudzikira, uye chiyero chekupfeka chinoderera neinopfuura 50% kana tembiricha ikapfuura 1200 ℃. Naizvozvo, kana dhaimani yekuchenesa yevacuum, tembiricha yekushongedza yekuvakisa inofanirwa kudzorwa pasi pe1200 ℃, uye dhigirii yekushongedza yevacuum haifanirwe kunge iri pasi pe5 × 10-2Pa.
(2) Sarudzo yesimbi yekuzadza simbi inonyanya kuenderana nekushandiswa kwayo uye kugadziriswa kwayo pamusoro. Kana ikashandiswa sechinhu chinodzivirira kupisa, simbi yekuzadza simbi ine tembiricha yakakwira yekuvhara uye inodzivirira kupisa zvakanaka inofanira kusarudzwa; Kune zvinhu zvinodzivirira ngura nemakemikari, simbi dzekuzadza simbi dzine tembiricha yakaderera yekuvhara uye inodzivirira ngura zvakanaka zvinosarudzwa. Kune graphite mushure mekugadzirisa simbi pamusoro, solder yemhangura yakachena ine ductility yakakwira uye inodzivirira ngura zvakanaka inogona kushandiswa. Solder inoshanda yakavakirwa pasirivha nemhangura ine kunyorova kwakanaka uye kuyerera kwe graphite nedhaimani, asi tembiricha yekushandira yejoini yakasungirirwa yakaoma kudarika 400 ℃. Kune zvikamu zve graphite nezvishandiso zvedhaimani zvinoshandiswa pakati pe400 ℃ ne800 ℃, base yegoridhe, base yepalladium, base yemanganese kana titanium base filler simbi dzinowanzo shandiswa. Kune majoini anoshandiswa pakati pe800 ℃ ne1000 ℃, simbi dzekuzadza dzakavakirwa pa nickel kana drill dzinofanira kushandiswa. Kana zvikamu zvegrafiti zvichishandiswa pamusoro pe1000 ℃, simbi dzakachena dzesimbi (Ni, PD, Ti) kana simbi dzine alloy filler dzine molybdenum, Mo, Ta nezvimwe zvinhu zvinogona kugadzira makabhohaidhiretsi nekabhoni zvinogona kushandiswa.
Kune graphite kana dhaimani isina kugadziriswa pamusoro, simbi dzinoshanda dzekuzadza dziri mutafura 16 dzinogona kushandiswa pakushongedza zvakananga. Zvizhinji zvesimbi idzi dzekuzadza dzakagadzirwa netitanium kana kuti ternary alloys. Titanium yakachena inobatana zvakasimba negrafiti, iyo inogona kuumba carbide layer yakakora kwazvo, uye linear expansion coefficient yayo yakasiyana zvikuru neye graphite, iyo iri nyore kuburitsa mitswe, saka haigone kushandiswa se solder. Kuwedzera Cr naNi kuTi kunogona kuderedza melting point uye kunatsiridza wettability ne ceramics. Ti i ternary alloy, inonyanya kuumbwa neTi Zr, nekuwedzera TA, Nb nezvimwe zvinhu. Ine low coefficient ye linear expansion, iyo inogona kuderedza brazing stress. Ternary alloy inonyanya kuumbwa neTi Cu yakakodzera brazing ye graphite nesimbi, uye joint ine high corrosion resistance.
Tafura 16 simbi dzekuzadza brazing dzekushandisa zvakananga graphite nedhaimani
(3) Maitiro ekugadzira simbi, nzira dzekugadzira simbi dzegraphite dzinogona kukamurwa kuita mapoka maviri, rimwe nderekugadzira simbi mushure mekugadzirwa kwesimbi pamusoro, uye rimwe nderekugadzira simbi pasina kugadziriswa pamusoro. Hazvina mhosva kuti ndeipi nzira inoshandiswa, weldment inofanira kugadziriswa isati yagadzirwa, uye tsvina yepamusoro yezvinhu zvegraphite inofanira kupukutwa nedoro kana acetone. Kana simbi iri pamusoro, jira reNi, Cu kana jira reTi, Zr kana molybdenum disilicide rinofanira kuputirwa pamusoro pegraphite neplasma spray, uye ipapo simbi yekuzadza yakagadzirwa necopper based filler kana sirivha inoshandiswa kugadzira simbi. Kugadzira simbi zvakananga ne active solder ndiyo nzira inonyanya kushandiswa pari zvino. Kupisa kwekugadzira simbi kunogona kusarudzwa zvichienderana ne solder yakapihwa mutafura 16. Solder inogona kusungirirwa pakati pejointi yakasungirirwa kana pedyo nemugumo mumwe. Pakugadzira simbi ine coefficient yakakura yekuwedzera kwekupisa, Mo kana Ti ine ukobvu hwakati inogona kushandiswa sechikamu chepakati chebuffer. Chigadziko chekuchinja chinogona kukonzera kushanduka kwepurasitiki panguva yekupisa kwesimbi, kutora kushushikana kwekupisa uye kudzivirira kuputika kwegirafiti. Semuenzaniso, Mo inoshandiswa senzvimbo yekuchinja yekusimbisa girafiti ye graphite ne hastelloyn. B-pd60ni35cr5 solder ine simba rakanaka rekukunda ngura nemwaranzi yakanyungudutswa inoshandiswa. Tembiricha yesimbi yesimbi i1260 ℃ uye tembiricha inochengetwa kwemaminitsi gumi.
Dhaimani yechisikigo inogona kuputirwa zvakananga ne b-ag68.8cu16.7ti4.5, b-ag66cu26ti8 nedzimwe solders dzinoshanda. Kuputirwa kunofanira kuitwa pasi pe vacuum kana low argon protection. Kupisa kwekubikira hakufanirwe kudarika 850 ℃, uye mwero wekupisa unokurumidza kusarudzwa. Nguva yekubata patembiricha yekubikira haifanirwe kunge yakareba (kazhinji inenge 10s) kudzivirira kuumbwa kwe tic layer inoenderera mberi panzvimbo inopindirana. Pakubirwa dhaimani nesimbi ye alloy, plastic interlayer kana low expansion alloy layer inofanira kuwedzerwa kuti ishandurwe kudzivirira kukuvara kwedhaimani kunokonzerwa nekumanikidzwa kwakanyanya kwekupisa. Chishandiso chekutenderedza kana chishandiso chinofinha chekugadzira machines e ultra precision chinogadzirwa ne brazing process, iyo inoputira 20 ~ 100mg small particle diamond pa steel body, uye simba re brazing joint rinosvika 200 ~ 250mpa
Dhaimani yepolycrystalline inogona kuputirwa nemurazvo, mafrequency akawanda kana vacuum. Kuputirwa kwemafrequency akawanda kana kuputirwa kwemurazvo kunofanirwa kushandiswa pakucheka simbi kana dombo nedhaimani. Simbi yeAg Cu Ti inoshanda yekuzadza simbi ine poindi yakaderera yekunyunguduka inofanira kusarudzwa. Tembiricha yekuvhara inofanira kudzorwa pasi pe850 ℃, nguva yekupisa haifanirwe kureba zvakanyanya, uye mwero wekutonhodza unononoka unofanirwa kushandiswa. Zvidimbu zvedhaimani zvepolycrystalline zvinoshandiswa mupetroleum uye geological drilling zvine mamiriro ekushanda asina kunaka uye zvinotakura mitoro yakakura. Simbi yekuzadza simbi yenickel inogona kusarudzwa uye foil yemhangura yakachena inogona kushandiswa sechikamu chekubatanidza kuputirwa kwevacuum. Semuenzaniso, 350 ~ 400 capsules Ф 4.5 ~ 4.5mm columnar polycrystalline diamond inoputirwa mumaburi e35CrMo kana 40CrNiMo steel kuti igadzire mazino ekucheka. Kuisa simbi muchina wekubvisa ...
Munguva yekushongedza, huremu hweweldment hunofanira kushandiswa pakusanganisa nekuisa zvinhu munzvimbo imwe chete sezvinobvira kuti chikamu chesimbi chidzvanye graphite kana polycrystalline zvinhu zviri pamusoro. Pakushandisa fixture pakuiisa panzvimbo imwe chete, fixture zvinhu zvinofanira kunge zviri zvinhu zvine thermal expansion coefficient yakafanana neyeweldment.
Nguva yekutumira: Chikumi-13-2022