Ukushisela Nge-Laser – Ithonya Lamapharamitha Okushintshashintshayo Kumodi Yendandatho Elungisekayo (i-ARM) Ukushisela Nge-Laser Kwama-Aluminium Alloys

Ukushisela Nge-Laser – Ithonya Lamapharamitha Okushintshashintshayo Kumodi Yendandatho Elungisekayo (i-ARM) Ukushisela Nge-Laser Kwama-Aluminium Alloys

1. Isifinyezo

Lolu cwaningo luhlola imiphumela ye-oscillation amplitude kanye nemvamisa kukhwalithi yobuso, izakhiwo ezinkulu nezincane, kanye ne-porosity yemodi yendandatho elungisekayo (i-ARM)okushiselwe nge-laser oscillatingAmapuleti e-aluminium alloy e-A5083. Imiphumela ikhombisa ukuthi ngokwanda kokuphakama kokuguquguquka kanye nemvamisa, ikhwalithi yobuso be-weld iyathuthuka. Njengoba ubukhulu banda, ingxenye ye-weld ishintsha kusuka esimweni "se-goblet" iye esimweni "se-crescent". Ukuhlaziywa kwesakhiwo se-microstructural kubonisa ukuthi usayizi wezinhlamvu ze-weld awunciphi ngokwanda kokuphakama kokuguquguquka kanye nemvamisa ngenxa yokuncintisana phakathi komphumela wokuxuba kanye nokwehla kwesilinganiso sokupholisa. I-weld porosity iyancipha ngokwanda kwamapharamitha e-oscillation, ifinyelela ku-porosity yokugcina engu-0.22% lapho ubukhulu bungu-2 mm. I-X-ray tomography enezinhlangothi ezintathu iqinisekisa ngokwengeziwe ithonya lokuguquguquka ekusabalaleni kwama-pore: ama-pore amakhulu avame ukuhlangana ngemuva kwechibi elincibilikisiwe, kuyilapho ama-pore amancane ebonisa ukulingana okungcono. Lolu cwaningo lunikeza ukuqonda okubalulekile kokwenza ngcono amapharamitha e-oscillation ukuze kufezwe ukushiswa kwe-laser kwekhwalithi ephezulu kuzinhlelo zokusebenza ze-aluminium alloy ze-A5083.

2 Isizinda Semboni

Ama-alloy e-aluminium anezinzuzo zesisindo esilula, amandla aphezulu athile, kanye nokumelana okuhle nokugqwala, futhi asetshenziswa kabanzi ezimotweni, ezitimeleni zesivinini esikhulu, ezindiza kanye nakwezinye izimboni. Ukushisela nge-laser kunezinzuzo zokusebenza kahle kakhulu, indawo encane ethintekile ekushiseni, kanye nokuguquguquka okuncane kokushisela. Ngakho-ke,Ukushisela nge-laser kuyindlela yokushisela engabizi kakhulu efanelekile kumapuleti amakhulu, okunganciphisa kakhulu inani lokudlula kwe-weld. I-Porosity iyiphutha elikhulu ekushiseni nge-laser kwama-aluminium alloys, elithinta kakhulu izakhiwo zemishini zamajoyinti ashiselwe. Ngakho-ke, kwenziwe izifundo eziningi zokunciphisa nokuqeda ukwakheka kwe-porosity, okuhlanganisa nokwenza ngcono igesi yokuvikela, ukusebenzisa ubuchwepheshe be-dual-beam, ukusebenzisa izinhlelo zamandla e-laser ezilungisiwe, kanye nokusebenzisa izindlela ze-oscillating beam. Ubuchwepheshe be-laser oscillating welding buvelele ngekhono labo lokuhlanganisa izinzuzo ze-laser welding nezici zabo. Ukusebenzisa i-laser oscillating welding akugcini nje ngokunciphisa i-porosity kodwa futhi kuthuthukise isakhiwo esincane se-weld futhi kuthuthukise ikhwalithi ye-weld. Inani elikhulu lezifundo ligxile kakhulu ezicini ezahlukahlukene ze-laser oscillating welding, okuhlanganisa ukunciphisa i-porosity, ukwenza ngcono ukusatshalaliswa kwamandla, ukulungiswa kwesakhiwo sokusanhlamvu, kanye nokucaciswa kokugeleza kokuncibilika echibini elincibilikisiwe. Ukusatshalaliswa kwamandla e-laser kudlala indima ebalulekile ekusatshalalisweni kwezinga lokushisa kanye nokujula kokungena kwe-laser welding. Nge-amplitude ethile ye-oscillation, ngokwanda kwemvamisa yokuskena, inqubo ye-welding ishintsha kusuka ekushiseni okujulile kuya ekushiseni okungazinzile, futhi ekugcineni iye ekushiseni kwe-heat conduction. Imiphumela ikhombisa ukuthi ukwandisa ubukhulu bokuskena kanye nemvamisa kunganciphisa ukugoba, kodwa futhi kunciphise kakhulu ukujula kokungena kwe-weld, ngaleyo ndlela kuncishiswe izakhiwo zemishini ze-weld. Eminyakeni yamuva nje, kuye kwasungulwa i-laser yemodi yendandatho elungisekayo (i-ARM), ehlukanisa amandla e-laser ibe yi-core enobukhulu bamandla aphezulu kanye nendandatho enobukhulu bamandla aphansi, ehlose ukuzinzisa i-keyhole nokuthuthukisa ikhwalithi yokugoba. Abacwaningi basebenzise i-ARM laser oscillating welding ukugoba ama-aluminium alloys angu-6xxx anamandla aphezulu ngaphansi kwezilinganiso zamandla e-core/ring ezahlukene kanye nobubanzi be-oscillation. Imiphumela yokuhlola ikhombisa ukuthi isici esiyinhloko esithinta i-geometry ye-weld ububanzi be-oscillation, kunokuba kube yi-core-ring power ratio. Kodwa-ke, ukusatshalaliswa kwe-pore kanye nendlela yayo yokuvimbela ngaphansi kwe-superposition ye-oscillation kanye ne-ARM laser akukafundwa. Kuleli phepha, kusetshenziswa ubuchwepheshe obusha be-ARM laser oscillating welding ukuze kuncishiswe ukugoba kwe-weld, ukuthola ukujula okuphezulu kokungena kanye nekhwalithi engcono ye-weld. Kwenziwa ucwaningo olunzulu mayelana nokusatshalaliswa kwamandla e-laser, ukuziphatha okuguquguqukayo kwedamu elincibilikisiwe, kanye nesakhiwo esincane ngaphansi kwamaza ahlukene okunyakazisa kanye nama-amplitude.

3. Izinhloso Nezinqubo Zokuhlola

Ubuchwepheshe bokushisela obujikelezayo be-laser oscillating busetshenziswe ukushisela ama-alloy e-aluminium. Izinto eziyisisekelo (BM) kwakuyi-alloy ye-aluminium engu-5083-O enobukhulu obungu-300mm × 100mm × 5mm (ubude × ububanzi × ubukhulu), futhi ukwakheka kwamakhemikhali ayo kuboniswe etafuleni. Ngaphambi kokushisela, amasampula ayepholishwa ukuze kususwe ifilimu ye-oxide engaphezulu, bese ehlanzwa nge-acetone kubhavu we-ultrasonic imizuzu eyi-15 ukuze kususwe uwoyela wongaphezulu.uhlelo lokushisela lwe-laserikakhulukazi iqukethe irobhothi iKuka, i-TruDisk 8001 disk laser, kanye nesithwebuli se-galvanometer se-3D PFO. I-TruDisk 8001 disk laser yasetshenziswa njengomthombo we-laser wemodi yendandatho elungisekayo, enesilinganiso se-core/ring fiber esingu-100/400 μm kanye namandla aphezulu okukhipha angu-8 kW (ubude be-wavelength obungu-1030 nm, ipharamitha yekhwalithi ye-beam engu-4.0 mm·rad). I-laser beam yakhiwe yingxenye eyinhloko kanye nengxenye yendandatho, lapho i-laser engxenyeni eyinhloko ephakathi ikhiqiza khona imbobo yokhiye (60% yamandla e-laser), kanti i-laser engxenyeni yendandatho iqinisekisa ukusatshalaliswa okuhle kokushisa (40% yamandla e-laser), njengoba kuboniswe kuMfanekiso (b). Ubude obuqondile be-collimator kanye nelensi yokugxila bungu-138 mm kanye no-450 mm, ngokulandelana. Ngesikhathi senqubo yokushisela, ikhamera yesivinini esiphezulu ye-Phantom V1840 kanye nomthombo wokukhanya we-Cavilux ovame kakhulu kwasetshenziswa ukuqapha inqubo yokushisela ngesikhathi sangempela, ngesivinini sokudubula esingu-5000 fps kanye nesikhathi sokuchayeka esingu-1 μs. Kulesi sifundo, indlela yokujikisa kwe-beam eyindilinga, indlela yokunyakaza kwe-laser, kanye nesivinini esisheshayo kuchazwa njengoba kuboniswe esithombeni.

4 Imiphumela kanye nengxoxo

4.1 Izici Zokwakheka Kokushintshwa Kwe-Weld Ukwakheka kobuso bokushintshwa kwe-weld ngaphansi kwezindlela ezahlukene zokushintshwa kwe-laser kuboniswe esithombeni. Imiphumela ikhombisa ukuthi ubuso bokushintshwa kwe-weld yokwelulwa komugqa oqondile ojwayelekile buqinile (ubulukhuni obungu-78.01 μm), ngokuqhubeka okungekuhle kwama-ripple okushintshwa kanye nokusabalala okunganele kwe-weld. Ukwakheka kokushintshwa okunganele, ukuchitheka okukhulu, kanye nokusikwa okungaphansi nakho kwabonwa. Ngokwanda kobukhulu be-oscillation kanye nemvamisa, ubuso bokushintshwa buveza izikali zezinhlanzi eziminyene nezilinganayo. Ubulukhuni bobuso bokushintshwa kwe-welds obunama-amplitude okusheshisa angu-0.5 mm, 1 mm, kanye no-2 mm bungu-80.71 μm, 49.63 μm, kanye no-31.12 μm, ngokulandelana. Akukho ukungahambi kahle noma ukuvela okubangelwa ukushintshwa kwe-spatter. Imiphumela ikhombisa ukuthi imvamisa ephezulu yokushintshwa kwe-oscillation iholela ekugelezeni okuvamile kwechibi elincibilikisiwe, umphumela oqinile wokushukumisa we-laser beam, kanye nobuso bokushintshwa obufanele kakhulu. Ngokuyisisekelo, ukuma kwe-laser weld kuhlobene ngokubangela ukunyakaza kogongolo lwe-laser. Ngesikhathi sokushisela, izinguquko ku-amplitude ye-oscillation kanye nemvamisa kushintsha isivinini sokushisela, ngaleyo ndlela kuthinte ubuningi bamandla aqondile kanye nokufakwa kokushisa okuphelele kwe-laser. Ukwakheka kwe-cross-sectional kwe-weld kufana ne-"goblet", okuhlanganisa izingxenye ezimbili: ingxenye engezansi "yisiqu", kanti ingxenye engenhla "yisitsha". Ukujula kokungena kanye "nesiqu" kuchazwa njenge-H1 ne-H2, ngokulandelana, kanti ububanzi be-weld ("isitsha") kanye "nesiqu" kuchazwa njenge-W1 ne-W2, ngokulandelana. Zombili ububanzi be-weld i-W1 ne-W2 ziyanda ngokuvumelana nokwanda kwe-amplitude ye-oscillation, futhi i-morphology ye-weld ishintsha kancane kancane kusuka esimweni "se-goblet" kuya esimweni "se-crescent". Ubuningi obukhulu bamandla e-laser buvela ekuhlanganeni kwe-trajectory. Uma kuqhathaniswa Izibalo (b, d) kanye no-(c, e), kungabonakala ukuthi ukwanda kwemvamisa yokuskena kuzokwandisa indawo yokugqagqana kwendlela endleleni yokuskena, okwenza ukusatshalaliswa kwamandla e-laser kufane kakhulu. Kodwa-ke, ukwehla kobuningi bamandla obukhulu kuzoholela ekunciphiseni ukujula kokushisela.

4.2 Ukuziphatha Kwechibi Elincibilikisiwe Ukuze kucaciswe ithonya lendlela yokuskena ekuziphatheni kwechibi elincibilikisiwe, kwasetshenziswa uhlelo lwekhamera olusheshayo ukuze kubonwe inqubo yokuvela kwechibi elincibilikisiwe kanye nembobo yokhiye. Isithombe (a) sibonisa inqubo yokuvela kwechibi elincibilikisiwe ngaphansi kwendlela eqondile. Izibalo (bf) ziyimidwebo yokuvela kwechibi elincibilikisiwe ngaphansi kwamapharamitha ahlukene okunyakazisa. Ngokukhula kwemvamisa yokunyakazisa kanye nobukhulu, ingxenye yangemuva yechibi elincibilikisiwe iba yindilinga kakhulu ngenxa yokwanda kobubanzi bechibi elincibilikisiwe. Njengoba ubude bechibi elincibilikisiwe bukhula, ukuguquguquka kobuso okubangelwa ukuqhuma kwembobo yokhiye kuyancipha ngesikhathi sokusabalala emuva. Ngakho-ke, insimbi encibilikisiwe iqina kahle futhi njalo ekugcineni kwechibi elincibilikisiwe, yakha izikali zezinhlanzi ezifanayo neziqinile. Lesi sibalo sibonisa ushintsho lwendawo yokuvula imbobo yokhiye ngesikhathi sokushisela nge-laser, olutholakala ezithombeni zezithombe zesivinini esiphezulu sechibi elincibilikisiwe. Njengoba kuboniswe kuMfanekiso (a), ngesikhathi sokushisela imbobo yomugqa oqondile, usayizi wokuvula imbobo yokhiye ubonisa ukuguquguquka okusobala. Kubonwe izimo eziningana zokuvalwa kwembobo yokhiye (0 mm²), kanye nendawo evamile yokuvula imbobo yokhiye engu-0.47 mm². Ukwanda kwe-amplitude ye-oscillation kunganciphisa nokuguquguquka futhi kuthuthukise ukuzinza. Lokhu kungenxa yokuthi ekushiseni okushintshashintshayo, ingxenye enkulu yamandla isatshalaliswa kuzo zombili izinhlangothi. Ngakho-ke, indawo yokukhipha embobeni yokhiye iyanda, futhi i-amplitude ye-oscillation iyanda, ngaleyo ndlela kwandise indawo yokuvula. Ukwanda kwe-amplitude kwandisa ububanzi bokushukuma komsebe we-laser, okuholela ekwandiseni i-radius yokunyakaza okuvamile kwembobo yokhiye. Ngenxa ye-viscosity yensimbi encibilikisiwe kanye nengcindezi ye-hydrodynamic esebenza eduze kodonga lwembobo yokhiye, ukunyakaza kwamanje kwe-eddy kwenzeka echibini elincibilikisiwe le-welding eduze kokuvulwa kwembobo yokhiye. Ukwanda kwendawo yokuvula imbobo yokhiye kuthuthukisa ukuzinza kwayo, kugwema ukwakheka kwama-bubbles, futhi ngaleyo ndlela kuvimbela kakhulu ukugoba.

4.3 Isakhiwo Esincane Lesi sibalo sibonisa isimo se-EBSD sesigaba esinqamulayo se-weld ngaphansi kwamaza ahlukene okushintshashintshayo kanye nama-amplitude. Eduze komugqa wokuhlanganisa we-laser weld, izinhlamvu ze-columnar dendrite zikhula ziye enkabeni ye-weld. Njengoba kuboniswe kuMfanekiso (a), phakathi kwezifunda "zesitsha" kanye "neziqu", umehluko osobala ekusabalalisweni kwezinhlamvu ze-columnar ungabonakala. Izinhlamvu ze-columnar zisatshalaliswa ngesimo se-U odongeni "lwesitsha", kanti esifundeni "sesiqu", izinhlamvu ze-columnar zisatshalaliswa ngesimo se-U odongeni lwe-fusion. Ngesikhathi sokuqina kwe-weld, izinhlamvu eziqiniswe kancane endaweni ye-fusion zisebenza njengezindawo ze-nucleation zangaphambili ze-solidification futhi zikhula ngokuthanda ziqonde emngceleni wechibi elincibilikisiwe oqondene ne-gradient ephezulu yokushisa. Lesi simo senzeka ngoba ubukhulu bamandla aphezulu be-laser buholela ekushiseni ngokweqile ngaphakathi kwechibi lokushisela. I-gradient ephezulu yokushisa i-G kanye nesilinganiso sokukhula esimaphakathi i-R kwenza i-G/R ibe nkulu kunomkhawulo wokuguqulwa kwesakhiwo, okuholela ekwakhekeni kwezinhlamvu ze-columnar. I-gradient yokushisa i-G esikhungweni sokushisela iyancipha, okwenza isilinganiso se-G/R sehle kancane kancane ngaphansi komkhawulo wokuguqulwa kwesakhiwo esincane, sishintshele ezinhlamvini ezilinganayo. Izinhlamvu ezilinganayo zitholakala ezingxenyeni eziphakathi "zesitsha" kanye "nesiqu". Njengoba "isiqu" se-weld sincane futhi siseduze nezinto eziyisisekelo, siqina ngokuphelele ngaphambi kwesifunda "sesitsha" ngesikhathi sokupholisa. Ingxenye "yesiqu" esiqinile isebenza njengendawo ye-nucleation phansi "kwesitsha", ikhuthaza ukukhula okuphezulu kwezinhlamvu zekholomu. Lesi sibalo sibonisa izinqubo zokushisela eziqondile neziguquguqukayo. Kuboniswa ukuthi ushintsho oluqhubekayo lwesikhundla se-laser beam ekushiseleni okuguquguqukayo kwe-laser kuzokhulisa ubude bechibi elincibilikisiwe eliphakathi, kuphinde kuncibilikise insimbi esivele iqinile, okuholela ekwehleni kwesilinganiso sokukhula kwezinhlamvu r. Lokhu kungaholela ekwehleni kwe-G/R endaweni yokusanhlamvu elinganayo ephansi.

4.4 Ukusatshalaliswa Kwe-Porosity I-X-ray tomography enezinhlangothi ezintathu yasetshenziswa ukwenza ukuhlolwa okuphelele kwe-weld, ukuthola ukusatshalaliswa kwe-pore enezinhlangothi ezintathu ku-weld, njengoba kuboniswe esithombeni. I-Porosity ibalwa njengevolumu iyonke yama-pores ehlukaniswe yivolumu iyonke ye-weld. Ngokuqhathanisa isimo se-pore kanye nokusatshalaliswa kwama-weld e-laser oscillating welds aqondile kanye nama-weld e-circular laser oscillating welds, kutholakala ukuthi ama-weld e-laser oscillating welds aqondile aqukethe ama-pores amaningi amakhulu, ane-porosity engu-2.49%, ephakeme kakhulu kuneye-circular.ukushintshwa kwe-laser oscillating. Ngokuqhathanisa Izibalo (b, c) kanye no-(d, e), kungabonakala ukuthi ukwandisa imvamisa yokugobhoza kusiza ekuvimbeleni ukwakheka kwama-pores. Ukuqhathanisa Izibalo (b, d) kanye no-(c, e), kungabonakala ukuthi ukwanda kwe-amplitude yokugobhoza kudlala indima ebalulekile ekuvimbeleni ukwakheka kwama-pores. Lapho i-amplitude yokugobhoza ikhuliswa kakhulu ibe ngu-2 mm (Isithombe (f)), ama-porosity ancishiswa kakhulu abe ngu-0.22%, okushiya kuphela ama-pores amancane namancane. Lesi sibalo sibonisa ukusatshalaliswa kwendawo yama-pores ebangeni elihlukile ukusuka kumugqa ophakathi we-weld, okumelela ama-porosity ngokusekelwe kusayizi wendawo yama-pores. Ngokushisela umugqa oqondile, indawo yama-pores isatshalaliswa ngokulinganayo eceleni komugqa ophakathi we-weld, futhi kancane kancane iyancipha ngokukhuphuka kwebanga ukusuka kumugqa ophakathi we-weld. Imiphumela ikhombisa ukuthi ama-pores abangelwa yi-keyhole agxile kakhulu ngemuva kwechibi elincibilikisiwe kumugqa ophakathi we-weld. Ngokushisela okushintshashintshayo nge-laser, ukulingana kokusatshalaliswa kwama-pores kuba buthakathaka. Lesi sibalo sibonisa indawo yembobo ebangeni elihlukile ukusuka ebusweni be-weld, lapho umugqa obomvu umelela umngcele phakathi kwezifunda "zesitsha" kanye "neziqu". Endabeni yama-pores amakhulu amakhulu (Izibalo (ac)), indawo yembobo engaphezulu komngcele ingaphezu kuka-85%. Lokhu kungenxa yokuthi ukuguquka kwe-contour emngceleni omude we-itudinal kungenzeka kakhulu ukuthi kubambe ama-bubble echibini le-weld, futhi ama-bubble abanjwe avame ukuthuthela phezulu ngaphansi kwethonya lokuntanta. Endabeni yama-pores amancane amakhulu (Izibalo (df)), ama-pores agxile endaweni ngaphakathi kwe-0.5 mm ngaphansi komugqa womngcele. Isikhathi esifushane sokupholisa kanye nokunyakaza okuncane phezulu kungaba yizizathu zalesi simo.

5 Iziphetho

(1) Izindlela ezahlukene zokujikijela nge-laser zinemiphumela esobala ebusweni bokushisela. Ukuphakama okuphezulu kanye nokuphindaphinda kungathuthukisa ikhwalithi yobuso, kuyilapho amapharamitha okujikijela amakhulu kakhulu angandisa ubulukhuni futhi abangele amaphutha okugoba.

(2) Ukuma kwe-weld kunqunywa kakhulu yimingcele ye-laser oscillation, ethinta isivinini sokushisela, ukusatshalaliswa kwamandla, kanye nokufakwa kokushisa okuphelele. Ngokukhula kwe-amplitude ye-oscillation, isimo se-weld siyashintsha kusuka ku-"goblet" kuya ku-"crescent", futhi isilinganiso se-aspect siyehla.

(3) Ngokwanda kokuphakama kokuguquguquka kanye nokuphindaphinda, ichibi elincibilikisiwe liba banzi futhi ingxenye yangemuva iba yindilinga. Umphumela wokuguquguquka wandisa ubude bechibi elincibilikisiwe, okuzuzisa ukuphuma kwebhamuza kanye nokuqina okufanayo. Ngesikhathi sokushisela okuqondile, indawo yokuvula imbobo kakhiye iyashintshashintsha; uma kuqhathaniswa, lokhu kuguquguquka kungancishiswa, kuthuthukiswe ukuzinza kokushisela.

(4) Ukwandisa ubukhulu bokujikijela kanye nemvamisa kunciphisa kokubili i-gradient yokushisa kanye nesilinganiso sokukhula, okuzuzisa ekwakhekeni kobukhulu bokusanhlamvu okukhulu. Kodwa-ke, umphumela wokuvuselela nge-laser usiza ekucwengisiseni usayizi wokusanhlamvu kanye nokuthuthukisa amandla okuthungwa. Ngaphansi kwamapharamitha e-laser ahlukene, ubulukhuni bokushisela buhlala buzinzile, buphansi kancane kunobo bezinto eziyisisekelo, okungaba ngenxa yokulahlekelwa yi-magnesium ngokuhwamuka.

(5) I-X-ray tomography enezinhlangothi ezintathu ikhombisa ukuthi ukushisela okuqondile kunezimbobo eziphezulu (2.49%) kanye nevolumu enkulu yezimbobo kunezimbobo ezinyakazayo. Ukwandisa amapharamitha okushisela kunganciphisa kakhulu izimbobo, kuze kufike ku-0.22% lapho ubukhulu bungu-2 mm. Ukusatshalaliswa kwendawo yezimbobo kuyashintsha ngokushisela: izimbobo ezinkulu zihlangana ngemuva kwechibi elincibilikisiwe, kanti izimbobo ezincane zinokulingana okungcono. Izimbobo ezinkulu zisakazwa kakhulu ngaphezu komngcele phakathi kwezifunda "zesitsha" kanye "neziqu", kuyilapho izimbobo ezincane zigxile ngaphansi komngcele.