Walda ta Laser - Tasirin Sigogi na Oscillation akan Yanayin Zobe Mai Daidaitawa (ARM) Walda ta Laser na Aluminum Alloys

Walda ta Laser - Tasirin Sigogi na Oscillation akan Yanayin Zobe Mai Daidaitawa (ARM) Walda ta Laser na Aluminum Alloys

1. Takaitaccen Bayani

Wannan binciken yana bincika tasirin girman oscillation da mita akan ingancin saman, macro da ƙananan tsarin, da porosity na yanayin zobe mai daidaitawa (ARM)na'urar haɗa laser oscillatingFaranti na ƙarfe na aluminum na A5083. Sakamakon ya nuna cewa tare da ƙaruwar girman juyawa da mitar juyawa, ingancin saman walda yana inganta. Yayin da girman walda ke ƙaruwa, ɓangaren haɗin walda yana canzawa daga siffar "kwalba" zuwa siffar "masu haske". Binciken ƙananan tsari ya nuna cewa girman hatsi na walda ba ya raguwa tare da ƙaruwar girman juyawa da mita saboda gasa tsakanin tasirin juyawa da rage saurin sanyaya. Porosity na walda yana raguwa tare da ƙaruwar sigogin juyawa, yana kaiwa ga porosity na ƙarshe na 0.22% lokacin da girman ya kai 2 mm. X-ray tomography mai girma uku ya ƙara tabbatar da tasirin juyawa akan rarraba ramuka: manyan ramuka suna taruwa a bayan tafkin narke, yayin da ƙananan ramuka suna nuna mafi kyawun daidaito. Wannan binciken yana ba da fahimta mai mahimmanci don inganta sigogin juyawa don cimma walda mai inganci ta laser a cikin aikace-aikacen ƙarfe na aluminum na A5083.

2 Bayani Kan Masana'antu

Gilashin aluminum suna da fa'idodin nauyi mai sauƙi, ƙarfi mai ƙarfi, da juriya mai kyau ga tsatsa, kuma ana amfani da su sosai a cikin masana'antu na mota, layin dogo mai sauri, sararin samaniya da sauran masana'antu. Walda ta laser tana da fa'idodin inganci mai yawa, ƙaramin yanki da zafi ya shafa, da ƙananan lalacewar walda. Saboda haka,Walda ta Laser hanya ce mai araha wacce ta dace da faranti masu kauri, wanda zai iya rage yawan wucewar walda sosai. Porosity babban lahani ne a walda na laser na aluminum, wanda ke shafar halayen injiniya na gidajen haɗin walda sosai. Saboda haka, an gudanar da bincike mai zurfi don ragewa da kawar da samuwar porosity, gami da inganta iskar gas mai kariya, amfani da fasahar katako biyu, amfani da tsarin wutar lantarki na laser mai daidaitawa, da kuma ɗaukar hanyoyin katako mai juyawa. Fasahar walda mai juyawa ta Laser ta shahara saboda iyawarta ta haɗa fa'idodin walda na laser tare da halayenta. Amfani da walda mai juyawa ta laser ba wai kawai zai iya rage porosity ba har ma yana inganta tsarin walda da haɓaka ingancin walda. Yawancin bincike sun fi mayar da hankali kan fannoni daban-daban na walda mai juyawa ta laser, gami da rage porosity, inganta rarraba makamashi, inganta tsarin hatsi, da kuma halayyar kwararar narkewa a cikin tafkin narkakken. Rarraba makamashin laser yana taka muhimmiyar rawa a cikin rarraba zafin jiki da zurfin shigar walda na laser. A wani girman oscillation, tare da ƙaruwar mitar duba, tsarin walda yana canzawa daga walda mai zurfi zuwa walda mara ƙarfi, kuma a ƙarshe zuwa walda mai watsa zafi. Sakamakon ya nuna cewa ƙara girman da mitar dubawa na iya rage porosity, amma kuma yana rage zurfin shigar walda sosai, ta haka ne rage halayen injin walda. A cikin 'yan shekarun nan, an ƙirƙiri laser yanayin zobe mai daidaitawa (ARM), wanda ke raba makamashin laser zuwa tsakiya mai yawan kuzari da zobe mai ƙarancin kuzari, da nufin daidaita ramin maɓalli da inganta ingancin walda. Masu bincike sun yi amfani da walda mai juyawar laser na ARM don walda ƙarfe mai ƙarfi na aluminum mai 6xxx a ƙarƙashin rabon ƙarfin tsakiya/zobe daban-daban da faɗin oscillation. Sakamakon gwaji ya nuna cewa babban abin da ke shafar yanayin walda shine faɗin oscillation, maimakon rabon ƙarfin zobe na tsakiya. Duk da haka, ba a yi nazarin rarraba rami da tsarin hana shi a ƙarƙashin haɗin oscillation da laser na ARM ba. A cikin wannan takarda, an ɗauki sabuwar fasahar walda mai juyawar laser na ARM don rage porosity na walda, samun zurfin shigar ciki mafi girma da ingantaccen ingancin walda. An gudanar da cikakken bincike kan rarrabawar makamashin laser, halayyar narkakken wurin wanka, da kuma tsarin microstructure a ƙarƙashin mitoci da girma daban-daban na juyawa.

3. Manufofin Gwaji da Tsarin Aiki

An yi amfani da fasahar walda mai zagaye ta laser don walda ƙarfe na aluminum. Kayan tushe (BM) shine ƙarfe na aluminum 5083-O tare da girman 300mm × 100mm × 5mm (tsawo × faɗi × kauri), kuma an nuna abubuwan da ke cikin sinadaran a cikin tebur. Kafin walda, an goge samfuran don cire fim ɗin oxide na saman, sannan a tsaftace su da acetone a cikin wanka na ultrasonic na minti 15 don cire man saman.tsarin walda na lasergalibi ya ƙunshi robot Kuka, laser ɗin faifan TruDisk 8001, da na'urar daukar hoto ta galvanometer ta 3D. An yi amfani da laser ɗin faifan TruDisk 8001 azaman tushen laser mai daidaitawa na yanayin zobe, tare da rabon zare na tsakiya/zobe na 100/400 μm da matsakaicin ƙarfin fitarwa na 8 kW (tsawon raƙuman ruwa na 1030 nm, ma'aunin ingancin katako na 4.0 mm·rad). Hasken laser ɗin ya ƙunshi ɓangaren tsakiya da ɓangaren zobe, inda laser ɗin da ke cikin ɓangaren tsakiya na tsakiya ke samar da ramin maɓalli (60% na ƙarfin laser), kuma laser ɗin da ke cikin ɓangaren zobe yana tabbatar da kyakkyawan rarraba zafin jiki (40% na ƙarfin laser), kamar yadda aka nuna a Hoto (b). Tsawon mai da hankali na ruwan tabarau mai haɗa collimator da mai da hankali shine 138 mm da 450 mm, bi da bi. A lokacin aikin walda, an yi amfani da kyamarar Phantom V1840 mai sauri da kuma tushen haske mai yawan Cavilux don sa ido kan aikin walda a ainihin lokaci, tare da saurin harbi na 5000 fps da lokacin fallasa na 1 μs. A cikin wannan binciken, an bayyana hanyar juyawar hasken wutar lantarki ta zagaye, hanyar motsi ta laser, da saurin gaggawa kamar yadda aka nuna a cikin hoton.

Sakamako 4 da Tattaunawa

4.1 Halayen Tsarin Walda An nuna yanayin saman walda a ƙarƙashin nau'ikan yanayin juyawar laser daban-daban a cikin hoton. Sakamakon ya nuna cewa saman walda na walda madaidaiciyar layi na yau da kullun yana da kauri (ƙarfin 78.01 μm), tare da rashin ci gaba da ripples na walda da rashin isasshen yaɗuwar walda. An kuma lura da rashin isasshen samuwar walda, tsatsa mai tsanani, da kuma yankewa a ƙasa. Tare da ƙaruwar girman juyawa da mitar, saman walda yana nuna ma'aunin kifi mai yawa da iri ɗaya. Ƙarfin saman walda tare da girman juyawa na 0.5 mm, 1 mm, da 2 mm shine 80.71 μm, 49.63 μm, da 31.12 μm, bi da bi. Babu rashin daidaituwa ko fitowar da sprutter ke haifarwa. Sakamakon ya nuna cewa yawan juyawa yana haifar da kwararar ruwa na yau da kullun, ƙarfin motsawar hasken laser, da kuma saman walda mafi kyau. Ainihin ma'anar, siffar walda ta laser tana da alaƙa da motsi na hasken laser. A lokacin walda, canje-canje a cikin girman juyawa da mita suna canza saurin walda, wanda hakan ke shafar yawan kuzarin layi da jimlar shigar zafi na laser. Tsarin haɗin gwiwa na walda yana da siffar "goblet", wanda ya ƙunshi sassa biyu: ƙasan shine "ƙaramin", kuma saman shine "kwano". Zurfin shiga da "ƙaramin" an ayyana su azaman H1 da H2, bi da bi, kuma faɗin walda ("kwano") da "ƙaramin" an ayyana su azaman W1 da W2, bi da bi. Faɗin walda duka biyun W1 da W2 suna ƙaruwa tare da ƙaruwar girman juyawa, kuma yanayin walda yana canzawa a hankali daga siffar "goblet" zuwa siffar "ƙarshen". Matsakaicin yawan kuzarin laser yana bayyana a lokacin haɗuwar hanya. Idan aka kwatanta Figures (b, d) da (c, e), za a iya ganin cewa ƙaruwar mitar duba zai ƙara yankin haɗuwar hanya a kan hanyar duba, wanda hakan zai sa rarrabawar makamashin laser ta zama iri ɗaya. Duk da haka, raguwar yawan kuzarin da ke cikinta zai haifar da raguwar zurfin walda.

4.2 Halayyar Wurin Wanka Mai Narkewa Don fayyace tasirin hanyar duba yanayin wurin wanka mai narkewa, an yi amfani da tsarin kyamara mai sauri don lura da tsarin juyin halittar wurin wanka mai narkewa da ramin maɓalli. Hoto (a) yana nuna tsarin juyin halittar wurin wanka mai narkewa a ƙarƙashin hanyar madaidaiciya. Hotuna (bf) su ne zane-zanen juyin halittar wurin wanka mai narkewa a ƙarƙashin sigogi daban-daban na juyawa. Tare da ƙaruwar mitar juyawa da girma, ɓangaren baya na wurin wanka mai narkewa yana ƙara zagaye saboda faɗaɗa faɗin wurin wanka mai narkewa. Yayin da tsawon wurin wanka mai narkewa ke ƙaruwa, canjin saman da fashewar ramin maɓalli ke haifarwa yana raguwa yayin yaɗuwa ta baya. Saboda haka, ƙarfe mai narkewa yana taurare cikin sauƙi kuma akai-akai a ƙarshen bayan wurin wanka mai narkewa, yana samar da sikelin kifi mai kama da na walda mai yawa. Hoton yana nuna canjin yankin buɗe ramin maɓalli yayin walda ta laser, wanda aka samo daga hotunan daukar hoto mai sauri na wurin wanka mai narkewa. Kamar yadda aka nuna a Hoto (a), yayin walda madaidaiciya, girman buɗe ramin maɓalli yana nuna canje-canje a bayyane. An lura da misalai da dama na rufe ramin maɓalli (0 mm²), tare da matsakaicin yankin buɗe ramin maɓalli na 0.47 mm². Ƙara girman juyawar kuma na iya rage canzawa da inganta kwanciyar hankali. Wannan saboda a cikin walda mai juyawa, ana rarraba babban rabo na makamashi zuwa ɓangarorin biyu. Saboda haka, hanyar fita a kan ramin maɓalli tana faɗaɗa, kuma girman juyawar yana ƙaruwa, ta haka yana ƙara yankin buɗewa. Ƙara girman yana faɗaɗa kewayon juyawar hasken laser, wanda ke haifar da faɗaɗa radius na motsi na ramin maɓalli lokaci-lokaci. Saboda ɗanɗano na ƙarfe mai narkewa da matsin lamba na hydrodynamic da ke aiki kusa da bangon ramin maɓalli, motsi na eddy current yana faruwa a cikin tafkin walda da aka narke kusa da buɗe ramin maɓalli. Faɗaɗa yankin buɗe ramin maɓalli yana ƙara kwanciyar hankali, yana guje wa samuwar kumfa, don haka yana hana porosity sosai.

4.3 Tsarin Ƙararraki Hoton yana nuna yanayin EBSD na haɗin gwiwar walda a ƙarƙashin mitoci daban-daban na juyawa da girma. Kusa da layin haɗuwa na walda na laser, ƙwayoyin dendrite na columnar suna girma zuwa tsakiyar walda. Kamar yadda aka nuna a Hoto na (a), tsakanin yankunan "kwano" da "tushe", ana iya ganin bambance-bambance bayyanannu a cikin rarrabawar hatsi na columnar. Ana rarraba hatsi na columnar a siffar U tare da bangon "kwano", yayin da a yankin "tushe", ana rarraba hatsi na columnar a siffar U tare da layin haɗuwa. A lokacin ƙarfafa walda, ƙwayoyin da aka ɗan ƙarfafa a yankin haɗuwa suna aiki a matsayin wuraren nucleation don gaban ƙarfafawa kuma suna fifita girma a tsaye zuwa iyakar tafkin narke tare da alkiblar matsakaicin yanayin zafi. Wannan lamari yana faruwa ne saboda yawan ƙarfin laser yana haifar da zafi fiye da kima a cikin tafkin walda. Babban saurin zafi G da matsakaicin ƙimar girma R suna sa G/R ya fi girman matakin canza tsarin microstructure, wanda ke haifar da samuwar hatsi na columnar. Yanayin zafin jiki na G a tsakiyar walda yana raguwa, wanda ke haifar da raguwar rabon G/R a hankali a ƙasa da matakin canjin tsarin microstructure, yana canzawa zuwa hatsi masu daidaito. Hatsi masu daidaito suna cikin sassan tsakiya na "kwano" da "tushe". Tunda "tushe" na walda yana da kunkuntar kuma yana kusa da kayan tushe, yana taurare gaba ɗaya kafin yankin "kwano" yayin sanyaya. Sashen "tushe" mai ƙarfi yana aiki azaman wurin nucleation a ƙasan "kwano", yana haɓaka haɓakar hatsi masu haɗin gwiwa sama. Hoton yana nuna hanyoyin walda madaidaiciya da masu juyawa. An nuna cewa ci gaba da canjin matsayin hasken laser a cikin walda mai juyawa na laser zai ƙara tsawon wurin narkewar matsakaici, yana sake narkewar ƙarfe da aka riga aka ƙarfafa, wanda ke haifar da raguwar ƙimar haɓakar hatsi r. Wannan na iya haifar da raguwar G/R a cikin yankin hatsi mai daidaito ƙasa.

4.4 Rarraba Porosity An yi amfani da hoton X-ray mai girma uku don gudanar da cikakken bincike na walda, inda aka sami rarraba ramuka uku a cikin walda, kamar yadda aka nuna a cikin hoton. Ana ƙididdige porosity a matsayin jimlar girman ramuka da aka raba ta jimlar girman walda. Ta hanyar kwatanta yanayin rami da rarraba walda madaidaiciyar laser mai juyawa da walda zagaye mai juyawa, an gano cewa walda madaidaiciyar laser mai juyawa suna ɗauke da ƙarin ramuka masu girma, tare da porosity na 2.49%, wanda ya fi na zagaye girma sosai.walda mai juyawa na laserTa hanyar kwatanta Figures (b, c) da (d, e), za a iya ganin cewa ƙara yawan juyawa yana taimakawa wajen hana samuwar ramuka. Idan aka kwatanta Figures (b, d) da (c, e), za a iya ganin cewa ƙaruwar girman juyawa yana taka muhimmiyar rawa wajen hana samuwar ramuka. Lokacin da aka ƙara girman juyawa zuwa 2 mm (Hoto (f)), raguwar ramukan yana ƙara raguwa zuwa 0.22%, yana barin ƙananan ramuka da ƙananan ramuka kawai. Hoton yana nuna rarraba yankin ramuka a nisan daban-daban daga layin tsakiya na walda, yana wakiltar ramuka bisa girman yankin ramuka. Don walda madaidaiciya, yankin ramukan yana rarraba daidai gwargwado tare da layin tsakiya na walda, kuma a hankali yana raguwa tare da ƙaruwar nisa daga layin tsakiya na walda. Sakamakon ya nuna cewa ramukan da ramukan maɓalli suka haifar galibi suna taruwa ne a bayan tafkin 后壁 na tafkin da aka narke a layin tsakiya na walda. Don walda mai juyawa ta laser, daidaituwar rarraba ramukan yana raguwa. Wannan hoton yana nuna yankin rami a nisan da ke tsakanin saman walda, inda layin ja ke wakiltar iyaka tsakanin yankunan "kwano" da "tushe". A yanayin manyan ramuka masu ƙarfi (Figures (ac)), yankin ramin da ke sama da iyaka ya kai fiye da 85%. Wannan saboda canjin kusurwa a kan dogon iyakar itudinal yana da yuwuwar kama kumfa a cikin tafkin walda, kuma kumfa da aka makale suna ƙaura zuwa sama ƙarƙashin tasirin buoyancy. A yanayin ƙananan ramuka masu ƙarfi (Figures (df)), ramukan suna taruwa a cikin yankin da ke tsakanin 0.5 mm ƙasa da layin iyaka. Gajeren lokacin sanyaya da ƙaramin ƙaura sama na iya zama dalilan wannan lamari.

Kammalawa 5

(1) Yanayin juyawar laser daban-daban suna da tasiri a fili akan saman walda. Girma da mita mafi girma na iya inganta ingancin saman, yayin da manyan sigogin juyawa masu yawa na iya ƙara tauri da haifar da lahani mai lanƙwasa.

(2) Siffar walda galibi ana tantance ta ne ta hanyar sigogin juyawar laser, waɗanda ke shafar saurin walda, rarrabawar makamashi, da jimlar shigar zafi. Tare da ƙaruwar girman juyawa, yanayin walda yana canzawa daga "kwalba" zuwa "mafita", kuma rabon yanayin yana raguwa.

(3) Tare da ƙaruwar girman juyawa da mitar juyawa, tafkin narkewa yana faɗaɗa kuma ɓangaren baya yana zagaye. Tasirin juyawa yana ƙara tsawon tafkin narkewa, wanda ke da amfani ga tserewar kumfa da kuma ƙarfafawa iri ɗaya. A lokacin walda madaidaiciya, yankin buɗe ramin maɓalli yana canzawa; a takaice dai, ana iya rage wannan canjin, yana inganta daidaiton walda.

(4) Ƙara yawan juyawa da mitar juyawa yana rage saurin zafi da kuma saurin girma, wanda hakan yana da amfani ga samuwar manyan girman hatsi. Duk da haka, tasirin juyawar laser yana taimakawa wajen tsaftace girman hatsi da inganta ƙarfin laushi. A ƙarƙashin sigogin laser daban-daban, taurin walda ya kasance mai ƙarfi, ɗan ƙasa da na kayan tushe, wanda ƙila ya faru ne saboda asarar magnesium.

(5) Hoton X-ray mai girma uku ya nuna cewa walda madaidaiciya tana da mafi girman porosity (2.49%) da girman pores fiye da walda mai juyawa. Ƙara sigogin juyawa na iya rage porosity sosai, har ma ya kai 0.22% lokacin da girman ya kai 2 mm. Rarraba yankin pores yana canzawa tare da juyawa: manyan pores suna taruwa a bayan tafkin narke, kuma ƙananan pores suna da daidaito mafi kyau. Manyan pores galibi suna rarrabawa sama da iyaka tsakanin yankunan "kwano" da "ƙarfe", yayin da ƙananan pores suna taruwa a ƙarƙashin iyaka.