Kuwotcha kwa Aluminium Matrix Composites

(1) Makhalidwe a brazing ma aluminium matrix composites makamaka amaphatikiza tinthu (kuphatikiza ndevu) kulimbitsa ndi kulimbitsa ulusi. Zida zomwe zimagwiritsidwa ntchito kulimbikitsa makamaka B, CB, SiC, etc.

Pamene ma aluminium matrix composites akuwotchedwa ndikuwotchedwa, matrix Al ndi osavuta kuchitapo ndi gawo lolimbikitsa, monga kufalikira mwachangu kwa Si muzitsulo zodzaza ndi chitsulo choyambira ndikupanga wosanjikiza wotayirira. Chifukwa cha kusiyana kwakukulu kwa mzere wowonjezera wowonjezera pakati pa Al ndi gawo lolimbikitsa, kutentha kwachitsulo kosayenera kumayambitsa kupsinjika kwa kutentha pamawonekedwe, omwe ndi osavuta kuyambitsa kusweka. Kuphatikiza apo, kunyowa pakati pa zitsulo zodzaza ndi zitsulo zolimbitsa thupi ndizosauka, chifukwa chake nsonga yamadzi yophatikizika iyenera kuthandizidwa kapena zitsulo zoyatsira zitsulo ziyenera kugwiritsidwa ntchito, ndipo kupukuta kwa vacuum kuyenera kugwiritsidwa ntchito momwe mungathere.

(2) Brazing zinthu ndi ndondomeko B kapena SiC tinthu analimbitsa zotayidwa masanjidwewo nsanganizo akhoza brazed, ndi pamwamba mankhwala pamaso kuwotcherera zikhoza kuchitika ndi sandpaper akupera, waya burashi kuyeretsa, kutsuka mchere kapena electroless faifi tambala plating (❖ kuyanika makulidwe 0.05mm). Chitsulo chodzaza ndi s-cd95ag, s-zn95al ndi s-cd83zn, chomwe chimatenthedwa ndi lawi lofewa la oxyacetylene. Kuphatikiza apo, nyonga yayikulu yolumikizana imatha kupezeka mwa kukanda brazing ndi s-zn95al solder.

Vacuum brazing itha kugwiritsidwa ntchito polumikiza ma composites a Short Fiber Reinforced 6061 aluminium matrix. Pamaso brazing, pamwamba adzakhala pansi ndi 800 abrasive pepala pambuyo akupera, ndiyeno brazed mu ng'anjo pambuyo akupanga kuyeretsa mu acetone. Al Si brazing filler zitsulo zimagwiritsidwa ntchito makamaka. Pofuna kupewa kufalikira kwa Si muzitsulo zoyambira, chotchinga chotchinga cha aluminiyamu chotchinga chotchinga chingathe kuviikidwa pamwamba pazitsulo zophatikizika, kapena b-al64simgbi (11.65i-15mg-0.5bi) zitsulo zopangira zitsulo zokhala ndi mphamvu zochepa zowotcha zimatha kusankhidwa. Kutentha kosungunuka kwazitsulo zodzaza ndi 554 ~ 572 ℃, kutentha kwamoto kumatha kukhala 580 ~ 590 ℃, nthawi yowotcha ndi 5min, ndipo mphamvu yakumeta ubweya wa olowa ndi yayikulu kuposa 80mpa.

Kwa ma graphite tinthu tolimbitsa ma aluminium matrix composites, kuwotcha mu ng'anjo yoteteza mpweya ndiyo njira yopambana kwambiri pakadali pano. Pofuna kukonza kunyowa, Al Si solder yokhala ndi Mg iyenera kugwiritsidwa ntchito.

Monga momwe zimakhalira ndi aluminiyamu vacuum brazing, kunyowa kwa ma aluminium matrix composites kumatha kuwongolera bwino poyambitsa mg vapor kapena kuyamwa kwa Ti ndikuwonjezera kuchuluka kwa Mg.