Polumikiza chitsulo ndi aluminiyamu, momwe zinthu zimachitikira pakati pa maatomu a Fe ndi Al panthawi yolumikizirana zimapanga ma brittle intermetallic compounds (IMCs). Kupezeka kwa ma IMC amenewa kumachepetsa mphamvu ya makina yolumikizirana, chifukwa chake ndikofunikira kuwongolera kuchuluka kwa ma compounds awa. Chifukwa cha kupangidwa kwa ma IMC ndikuti kusungunuka kwa Fe mu Al ndi kochepa. Ngati kupitirira kuchuluka kwina, kungakhudze mawonekedwe a makina a weld. Ma IMC ali ndi mawonekedwe apadera monga kuuma, kusinthasintha kochepa komanso kulimba, komanso mawonekedwe a mawonekedwe. Kafukufuku wapeza kuti poyerekeza ndi ma IMC ena, gawo la Fe2Al5 IMC limaonedwa kuti ndi lofooka kwambiri (11.8).± 1.8 GPa) IMC gawo, ndipo ndiye chifukwa chachikulu cha kuchepa kwa mphamvu zamakina chifukwa cha kulephera kwa welding. Pepalali likufufuza njira yolumikizira ya laser yakutali ya IF steel ndi 1050 aluminiyamu pogwiritsa ntchito laser yosinthika ya ring mode, ndipo likufufuza mozama momwe mawonekedwe a laser beam amakhudzira mapangidwe a intermetallic compounds ndi mphamvu zamakina. Mwa kusintha chiŵerengero cha mphamvu ya core/ring, zidapezeka kuti pansi pa conduction mode, chiŵerengero cha mphamvu ya core/ring cha 0.2 chingapangitse bwino weld interface bonding surface area ndikuchepetsa kwambiri makulidwe a Fe2Al5 IMC, potero kumawonjezera mphamvu ya shear ya cholumikizira.
Nkhaniyi ikuwonetsa mphamvu ya laser yosinthika ya ring mode pakupanga ma intermetallic compounds ndi ma mechanical properties panthawi yolumikizira laser yakutali ya IF steel ndi 1050 aluminiyamu. Zotsatira za kafukufuku zikusonyeza kuti pansi pa conduction mode, core/ring power ratio ya 0.2 imapereka malo akuluakulu olumikizirana a weld interface, omwe amawonetsedwa ndi mphamvu yayikulu yolumikizira ya 97.6 N/mm2 (kulumikizana bwino kwa 71%). Kuphatikiza apo, poyerekeza ndi matabwa a Gaussian omwe ali ndi mphamvu yoposa 1, izi zimachepetsa kwambiri makulidwe a Fe2Al5 intermetallic compound (IMC) ndi 62% ndi makulidwe onse a IMC ndi 40%. Mu perforation mode, ming'alu ndi mphamvu yocheperako ya shear zinawonedwa poyerekeza ndi conduction mode. Ndikofunikira kudziwa kuti kukonzedwa kwakukulu kwa tirigu kunawonedwa mu weld seam pamene core/ring power ratio inali 0.5.
Pamene r=0, mphamvu yozungulira yokha imapangidwa, pomwe pamene r=1, mphamvu yoyambira yokha imapangidwa.
Chithunzi chojambula cha chiŵerengero cha mphamvu r pakati pa mtanda wa Gaussian ndi mtanda wa annular
(a) Chipangizo chowotcherera; (b) Kuzama ndi m'lifupi mwa mbiri ya chowotcherera; (c) Chithunzi chosonyeza zitsanzo ndi zokonzera
Mayeso a MC: Pokhapokha ngati pali beam ya Gaussian, msoko wa weld poyamba umakhala mu shallow conduction mode (ID 1 ndi 2), kenako umasinthira ku lockhole move yomwe imalowa pang'ono (ID 3-5), ndipo ming'alu yoonekeratu imawonekera. Pamene mphamvu ya mphete inakwera kuchoka pa 0 mpaka 1000 W, panalibe ming'alu yoonekeratu pa ID 7 ndipo kuya kwa chitsulo kunali kochepa. Pamene mphamvu ya mphete inakwera kufika pa 2000 ndi 2500 W (IDs 9 ndi 10), kuya kwa chitsulo cholemera kumawonjezeka. Kusweka kwakukulu pa mphamvu ya mphete ya 2500w (ID 10).
Mayeso a MR: Pamene mphamvu yapakati ili pakati pa 500 ndi 1000 W (ID 11 ndi 12), msoko wa weld uli mu conduction mode; Poyerekeza ID 12 ndi ID 7, ngakhale mphamvu yonse (6000w) ndi yofanana, ID 7 imagwiritsa ntchito lock hole mode. Izi zimachitika chifukwa cha kuchepa kwakukulu kwa mphamvu pa ID 12 chifukwa cha dominant loop characteristic (r=0.2). Pamene mphamvu yonse ifika 7500 W (ID 15), full penetration mode ingapezeke, ndipo poyerekeza ndi 6000 W yomwe imagwiritsidwa ntchito mu ID 7, mphamvu ya full penetration mode imawonjezeka kwambiri.
Mayeso a IC: Njira yoyendetsedwa (ID 16 ndi 17) idakwaniritsidwa pa mphamvu ya core ya 1500w ndi mphamvu ya ring ya 3000w ndi 3500w. Mphamvu ya core ikakhala 3000w ndipo mphamvu ya ring ili pakati pa 1500w ndi 2500w (ID 19-20), ming'alu yoonekera bwino imawonekera pakati pa chitsulo cholemera ndi aluminiyamu wolemera, ndikupanga mawonekedwe ang'onoang'ono olowera m'deralo. Mphamvu ya ring ikakhala 3000 ndi 3500w (ID 21 ndi 22), pezani njira yonse yolowera ndi keyhole.
Zithunzi zoyimira magawo osiyanasiyana a chizindikiro chilichonse chowotcherera pansi pa maikulosikopu yowala
Chithunzi 4. (a) Ubale pakati pa mphamvu yolimba kwambiri (UTS) ndi chiŵerengero cha mphamvu mu mayeso oweluza; (b) Mphamvu yonse ya mayeso onse oweluza
Chithunzi 5. (a) Ubale pakati pa chiŵerengero cha mbali ndi UTS; (b) Ubale pakati pa kufalikira ndi kuya kwa kulowa ndi UTS; (c) Kuchuluka kwa mphamvu pa mayeso onse olumikizirana
Chithunzi 6. (ac) Mapu a Vickers microhardness indentation contour; (df) Ma spectra a SEM-EDS chemical ofanana nawo oimira conduction mode welding; (g) Chithunzi cha Schematic cha kulumikizana pakati pa chitsulo ndi aluminiyamu; (h) Fe2Al5 ndi makulidwe onse a IMC a conductive mode welds
Chithunzi 7. (ac) Mapu a Vickers microhardness indentation contour; (df) Sewero la mankhwala la SEM-EDS lofanana ndi la welding yoyimira local penetration penetration mode welding
Chithunzi 8. (ac) Mapu a Vickers microhardness indentation contour; (df) Sewero la mankhwala la SEM-EDS lofanana ndi la welding yoyimira full penetration perforation mode welding
Chithunzi 9. Chithunzi cha EBSD chikuwonetsa kukula kwa tirigu wa dera lolemera ndi chitsulo (mbale yapamwamba) mu mayeso olowera mkati mwa njira yobowola, ndikuwerengera kukula kwa tirigu.
Chithunzi 10. Masewero a SEM-EDS a mawonekedwe a pakati pa chitsulo cholemera ndi aluminiyamu wolemera
Kafukufukuyu adafufuza zotsatira za laser ya ARM pa kapangidwe, kapangidwe kake, ndi kachitidwe ka makina a IMC mu maulumikizidwe a aluminiyamu a IF steel-1050 alloy dissimilar lap welded. Kafukufukuyu adaganizira njira zitatu zolumikizira (njira yoyendetsera, njira yolowera m'deralo, ndi njira yolowera yonse) ndi mawonekedwe atatu osankhidwa a laser beam (Gaussian beam, annular beam, ndi Gaussian annular beam). Zotsatira za kafukufukuyu zikusonyeza kuti kusankha chiŵerengero choyenera cha mphamvu ya Gaussian beam ndi annular beam ndi gawo lofunika kwambiri lowongolera mapangidwe ndi kapangidwe ka microstructure ka carbon yamkati, motero kukulitsa mphamvu zamakina za weld. Mu njira yoyendetsera, beam yozungulira yokhala ndi chiŵerengero cha mphamvu cha 0.2 imapereka mphamvu yabwino kwambiri yolumikizira (71% ya magwiridwe antchito a joint). Mu njira yoboola, beam ya Gaussian imapanga kuzama kwakukulu kwa welding ndi chiŵerengero chapamwamba cha aspect, koma mphamvu ya welding imachepa kwambiri. Beam ya annular yokhala ndi chiŵerengero cha mphamvu cha 0.5 imakhudza kwambiri kukonzanso kwa tinthu ta mbali yachitsulo mu weld seam. Izi zimachitika chifukwa cha kutentha kochepa kwa denga la annular komwe kumabweretsa kuzizira mwachangu, komanso kuletsa kukula kwa Al solute migration kupita kumtunda kwa weld seam pa kapangidwe ka tirigu. Pali mgwirizano wamphamvu pakati pa Vickers microhardness ndi Thermo Calc's assuming of phase volume percentage. Pamene voliyumu ya Fe4Al13 ikukula, microhardness imakwera.
Nthawi yotumizira: Januwale-25-2024
