(1) Makhalidwe a brazing a aluminiyamu matrix composites makamaka amaphatikizapo tinthu tating'onoting'ono (kuphatikiza ndevu) ndi ulusi wolimbitsa. Zipangizo zomwe zimagwiritsidwa ntchito polimbitsa makamaka ndi B, CB, SiC, ndi zina zotero.
Pamene zinthu zopangidwa ndi aluminiyamu zimayikidwa mu brass ndi kutentha, matrix Al imakhala yosavuta kuchita ndi gawo lolimbitsa, monga kufalikira mwachangu kwa Si mu chitsulo chodzaza ku chitsulo choyambira komanso kupangika kwa brittle dumping layer. Chifukwa cha kusiyana kwakukulu kwa linear expansion coefficient pakati pa Al ndi gawo lolimbitsa, kutentha kosayenera kwa brazing kumayambitsa kupsinjika kwa kutentha pamalo olumikizirana, zomwe zimakhala zosavuta kuyambitsa kusweka kwa mafupa. Kuphatikiza apo, kunyowa pakati pa chitsulo chodzaza ndi gawo lolimbitsa ndi koipa, kotero pamwamba pa brazing pa composite kuyenera kukonzedwa kapena chitsulo chodzaza choyambitsidwa chiyenera kugwiritsidwa ntchito, ndipo vacuum brazing iyenera kugwiritsidwa ntchito momwe mungathere.
(2) Zinthu zopangira zitsulo zomangira zitsulo ndi njira ya B kapena SiC tinthu tating'onoting'ono tolimba ta aluminiyamu zitha kupangidwa ndi brazing, ndipo kukonza pamwamba pake musanagwiritse ntchito kuwotcha kungachitike pogwiritsa ntchito sandpaper grinding, kutsuka burashi ya waya, kutsuka ndi alkali kapena electroless nickel plating (makulidwe a 0.05mm). Chitsulo chodzaza ndi s-cd95ag, s-zn95al ndi s-cd83zn, zomwe zimatenthedwa ndi lawi lofewa la oxyacetylene. Kuphatikiza apo, mphamvu yayikulu yolumikizirana ingapezeke pochotsa zitsulo zomangira zitsulo ndi s-zn95al solder.
Kuphimba kwa vacuum kungagwiritsidwe ntchito polumikiza zinthu zopangidwa ndi aluminiyamu ya Short Fiber Reinforced 6061. Musanapange chitsulo, pamwamba pake payenera kuphwanyidwa ndi pepala losakhwima la 800 mutamaliza kupukuta, kenako n’kuphwanyidwa mu uvuni mutatsuka ndi acetone pogwiritsa ntchito ultrasound. Chitsulo chodzaza cha Al Si chimagwiritsidwa ntchito kwambiri. Pofuna kupewa kufalikira kwa Si mu chitsulo choyambira, wosanjikiza wa chotchinga cha aluminiyamu choyera ukhoza kuphimbidwa pamwamba pa chitsulo chophatikiza, kapena b-al64simgbi (11.65i-15mg-0.5bi) chitsulo chodzaza ndi mphamvu yochepa ya brazing chingasankhidwe. Kutentha kosungunuka kwa chitsulo chodzaza ndi 554 ~ 572 ℃, kutentha kwa brazing kungakhale 580 ~ 590 ℃, nthawi ya brazing ndi mphindi 5, ndipo mphamvu yodula ya cholumikizira ndi yoposa 80mpa.
Pa zinthu zopangidwa ndi aluminiyamu zolimbitsa tinthu ta graphite, kugwiritsa ntchito chitsulo choteteza mu uvuni wa atmosphere ndiyo njira yopambana kwambiri pakadali pano. Pofuna kunyowetsa madzi, Al Si solder yokhala ndi Mg iyenera kugwiritsidwa ntchito.
Monga momwe zimakhalira ndi aluminium vacuum brazing, kunyowa kwa ma aluminium matrix composites kumatha kusinthidwa kwambiri poika mg vapor kapena Ti suction ndikuwonjezera kuchuluka kwa Mg.
Nthawi yotumizira: Juni-13-2022