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Wani sabon inji dangane da zaɓaɓɓen Laser narkewa don sarrafa microstructure na samfurori a cikin masana'antu tsari da aka proposed.The inji dogara a kan ƙarni na high-inna ultrasonic taguwar ruwa a cikin narkakkar pool ta hadaddun tsanani-modulated Laser irradiation.Gwaji karatu da lambobi simulations nuna cewa wannan iko inji ne fasaha mai yiwuwa ne kuma za a iya yadda ya kamata hadedde a cikin narke zane na zamani Laser.
Additive masana'antu (AM) na hadaddun-dimbin yawa sassa ya girma muhimmanci a cikin 'yan shekarun nan. Duk da haka, duk da iri-iri na ƙari masana'antu matakai, ciki har da zabi Laser narkewa (SLM) 1,2,3, kai tsaye Laser karfe deposition4,5,6, lantarki katako melting7,8 da others9,10, da Parts na iya zama m.This shi ne yafi saboda da takamaiman halaye na narkakken narke, da sanyi hadaddun da high diamita da dumama tsari, da sanyi hadaddun da high diamita. hawan keke a cikin narkewa da kayan gyarawa11, wanda ke haifar da haɓakar hatsi na epitaxial da mahimmancin porosity12,13.Sakamakon ya nuna cewa , wajibi ne don sarrafa thermal gradients, sanyaya rates, da gami abun da ke ciki, ko amfani da ƙarin girgiza jiki ta hanyar waje filayen daban-daban Properties (misali, duban dan tayi) don cimma lafiya equiaxed hatsi Tsarin.
Yawancin wallafe-wallafe suna damuwa da tasirin jiyya na jiyya a kan tsarin ƙarfafawa a cikin tsarin simintin al'ada na al'ada14,15.Duk da haka, yin amfani da filin waje zuwa girma narke ba ya samar da abin da ake so microstructure1.If the girma na ruwa lokaci ne kananan, halin da ake ciki canje-canje dramatically.In wannan harka, da waje filin muhimmanci rinjayar da solidification process.Electromagnetic, , a lokacin 19 , an yi la'akari da sakamako na 19 mai tsanani. 22,23,24,25,26,27, baka stirring28 da oscillation29, pulsed plasma arcs30,31 da sauran hanyoyin32 .Haɗa zuwa ga substrate ta yin amfani da wani waje high-tsanani duban dan tayi Madogararsa (a 20 kHz) .A duban dan tayi-jawo da gyare-gyaren hatsi da aka dangana ga ƙãra shiyyar haɓakaccen haɓakaccen haɓakaccen ƙwayar cuta ta hanyar haɓakaccen haɓakaccen ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar ƙwayar cuta. .
A cikin wannan aikin, mun bincika yiwuwar musanya tsarin hatsi na austenitic bakin karfe ta hanyar sonicating da narkakkar pool tare da sauti tãguwar ruwa generated da narkewa Laser kanta.The tsanani modulation na Laser radiation ya faru a kan haske-amsar matsakaici sakamakon a cikin ƙarni na ultrasonic tãguwar ruwa, wanda canza da microstructure na material.This tsanani zama modulation a cikin hadedde tabo aikin Laser iya zama mai sauƙi a yi a cikin Laser Sulters.This tsanani modulation a cikin data kasance gwaji. faranti na karfe wanda aka fallasa su zuwa radiation laser mai tsanani-modulated.Saboda haka, a fasaha, ana yin maganin laser. Duk da haka, idan an yi irin wannan maganin laser a saman kowane Layer, yayin da ake ginawa Layer-by-Layer, ana samun sakamako akan dukan ƙarar ko a kan sassan da aka zaɓa na ƙarar.
Ganin cewa a cikin ultrasonic ƙaho na tushen ultrasonic far, da ultrasonic makamashi na ultrasonic makamashi na tsaye sauti kalaman da aka rarraba a ko'ina cikin bangaren, yayin da Laser-jawo ultrasonic tsanani ne sosai mayar da hankali a kusa da batu inda Laser radiation ne absorbed.Amfani da sonotrode a cikin wani SLM foda gado fusion inji yana da rikitarwa saboda saman surface na foda gado fallasa zuwa Laser radiation ya kamata ya kasance a tsaye a saman, babu wani surface danniya. sifili da barbashi gudu yana da matsakaicin amplitude a kan dukan saman saman na part. The sauti matsa lamba a cikin dukan narkakkar pool ba zai iya wuce 0.1% na matsakaicin matsa lamba generated da waldi shugaban, saboda da wavelength na ultrasonic taguwar ruwa tare da mita na 20 kHz a bakin karfe ne \ (\ SIM 0.3 ~ \ rubutu da \ (\ sim 0.3 ~ \ rubutu da zurfin \ 3 = 3 ~ 3 ~ 3 ~ 3 ~ № № 3 ~ 3 ~ 3 ~ 3 ~ 3 ~ № № 3 № 3 ~ 3 ~ 3 ~ 3 ~ 3 ~ 3 ~ 3 ~ 3 = 3 = 3 3 ~ . sabili da haka, sakamakon duban dan tayi akan cavitation na iya zama ƙananan.
Ya kamata a lura da cewa yin amfani da tsanani-modulated Laser radiation a kai tsaye Laser karfe jiba shi ne wani aiki yanki na bincike35,36,37,38.
The thermal sakamako na Laser radiation abin da ya faru a kan matsakaici shi ne tushen kusan duk Laser dabaru 39, 40 ga kayan aiki, irin su cutting41, waldi, hardening, drilling42, surface tsaftacewa, surface alloying, surface polishing43, etc.The sabuwar dabara na Laser ta da sabon aukuwa a cikin kayan sarrafa dabaru, da na farko sakamakon da aka taƙaita, 45 monographs da yawa.
Ya kamata a lura da cewa duk wani ba na tsaye mataki a kan matsakaici, ciki har da lasing mataki a kan sha matsakaici, sakamakon a cikin tashin hankali na acoustic tãguwar ruwa a cikinta tare da fiye ko žasa yadda ya dace.Da farko, babban mayar da hankali shi ne a kan Laser tashin hankali na tãguwar ruwa a cikin ruwa da kuma daban-daban thermal excitation hanyoyin na sauti (thermal fadada, evaporation, 4 juzu'in canji, lokaci guda 4 , lokaci 4, da dai sauransu) N. s50, 51, 52 suna ba da nazari na ka'idar wannan tsari da kuma yuwuwar aikace-aikacen sa.
Wadannan al'amurran da suka shafi da aka daga baya tattauna a daban-daban taro, da kuma Laser tashin hankali na duban dan tayi yana da aikace-aikace a cikin biyu masana'antu aikace-aikace na Laser technology53 da kuma medicine54.Saboda haka, shi za a iya la'akari da cewa ainihin ra'ayi na aiwatar da pulsed Laser haske ayyuka a kan wani absorbing matsakaici da aka found.Laser ultrasonic dubawa da ake amfani da lahani ganewa na SLM-kerarre samfurori55,56.
Sakamakon Laser-generated shock tãguwar ruwa a kan kayan ne tushen Laser girgiza peening57,58,59, wanda kuma aka yi amfani da surface jiyya na additively kerarre sassa60.Amma, Laser girgiza ƙarfafa ne mafi tasiri a kan nanosecond Laser bugun jini da mechanically ɗora Kwatancen saman (misali, tare da Layer na ruwa)59 saboda inji loading ƙara ganiya matsa lamba.
An gudanar da gwaje-gwaje don bincika yiwuwar tasirin filayen jiki daban-daban akan microstructure na kayan aiki masu ƙarfi. An nuna zane mai aiki na saitin gwaji a cikin Hoto 1. A pulsed Nd: YAG m-jihar Laser aiki a cikin free-gudu yanayin (pulse duration \ (\ tau _L \ sim 150 ~ upmu \ rubutu {s} \) An yi amfani da wani tsaka-tsaki na Laser. ter farantin tsarin.Ya danganta da hade tsaka tsaki yawa filters, bugun jini makamashi a kan manufa dabam daga \ (E_L \ sim 20 ~\ rubutu {mJ} \) zuwa \ (E_L \ sim 100 ~\ rubutu {mJ} \) . The Laser katako nuna daga katako splitter ne ciyar da wani photodiode mai tsawo da kuma lokaci guda photodiode (lokacin photodiode). \ (1 ~\ rubutu {ms} \)) ana amfani da su domin sanin abin da ya faru zuwa da kuma nuna daga manufa, da kuma biyu ikon mita (photodiodes tare da gajeren amsa lokuta \ (<10 ~\ rubutu {ns}\)) don sanin abin da ya faru da kuma nuna ikon gani. a wurin samfurin. Mai da hankali kan katako a kan manufa ta yin amfani da ruwan tabarau (Antireflection shafi a \ (1.06 \ upmu \ rubutu {m} \), tsayin tsayi \ (160 ~ \ rubutu {mm} \)) da kullin katako a farfajiyar manufa 60- \ (100 ~ \ upmu \ rubutu {m} \).
Zane-zane na aiki na saitin gwaji: 1-laser;2 - Laser katako;3-tsatsa mai yawa tace;4 - photodiode da aka daidaita;5 - mai raba katako;6- diaphragm;7 - calorimeter na abin da ya faru;8 - calorimeter na katako mai haske;9- Mitar wutar lantarki da ya faru;10 - mitar wutar lantarki mai nunawa;11 - ruwan tabarau mai mayar da hankali;12 - madubi;13 - samfurin;14 - mai watsa shirye-shiryen piezoelectric mai watsa shirye-shirye;15 - 2D mai canzawa;16 - sanya microcontroller;17 - naúrar aiki tare;18 - Multi-tashar dijital saye tsarin tare da daban-daban samfurin rates;19 – kwamfuta ta sirri.
Ana gudanar da magani na ultrasonic kamar haka. Laser yana aiki a cikin yanayin gudana kyauta;saboda haka da duration na Laser bugun jini ne \ (\ tau _L \ sim 150 ~ \ upmu \ rubutu {s} \ ), wanda ya ƙunshi mahara durations na kusan \ (1.5~\upmu \ rubutu {s } \) kowane. The temporal siffar da bugun jini Laser da bakan kunshi wani low-mita ambulaf da modulation na \ 7 MHz , da matsakaita \ 7. kamar yadda aka nuna a cikin Hoto 2.- Ambulan mitar yana samar da dumama da narkewa mai zuwa da kuma fitar da kayan aiki, yayin da babban ɓangaren mita yana samar da vibrations ultrasonic saboda tasirin photoacoustic.The waveform na ultrasonic bugun jini generated da Laser aka yafi ƙaddara da lokaci siffar da Laser bugun jini tsanani.Ya fito ne daga \ (7 ~\ rubutu {kHz} \) zuwa \ (2 ~ \ rubutu {MHz} \), kuma tsakiyar mita shine \ (~ 0.7 ~\ rubutu {MHz} \) . An yi rikodin bugun jini saboda tasirin photoacoustic ta amfani da transducers na broadband piezoelectric transducers sanya daga polyvinylidene fluoride fina-finai. The rikodin kalaman na fluoride fina-finan ya kamata a nuna a cikin Laser siffar. na hali na Laser yanayin mai gudana kyauta.
Rarraba na ɗan lokaci na ƙarfin bugun bugun laser (a) da saurin sauti a saman baya na samfurin (b), nau'ikan bugun jini na laser (c) da bugun jini na ultrasonic (d) sun daidaita sama da 300 bugun bugun laser (ja mai lanƙwasa) don bugun bugun laser guda ɗaya (launi shuɗi) .
Za mu iya bayyana a fili bambance-bambancen ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙwayoyin jiyya da suka dace da ƙananan ambulaf na bugun jini na Laser da gyare-gyare mai mahimmanci, bi da bi.sabili da haka, ana sa ran babban tasirin babban mitar watsa shirye-shirye na siginar sauti akan microstructure.
Hanyoyin jiki a cikin SLM suna da rikitarwa kuma suna faruwa a lokaci guda a kan ma'auni daban-daban na sararin samaniya da na wucin gadi.Saboda haka, hanyoyi masu yawa sun fi dacewa da nazarin ka'idar SLM.Mathematical model ya kamata da farko ya zama nau'i-nau'i.
Adadin dumama da sanyaya har zuwa \(10^6~\rubutu {K}/\rubutu {s}\) /\rubutu{saboda gurɓataccen iska da iska mai ƙarfi da ƙarfin wuta har zuwa \(10^{13}~\rubutu {W} cm}^2\).
Zagayowar narkewa-ƙarfafa yana wanzuwa tsakanin 1 da \(10~\rubutu {ms}\), wanda ke ba da gudummawa ga saurin ƙarfafa yankin narkewa yayin sanyaya.
Rapid dumama na samfurin surface sakamakon a cikin samuwar high thermoelastic danniya a cikin surface Layer.Ya isa (har zuwa 20%) rabo na foda Layer ne karfi da evaporated63, wanda results a cikin wani ƙarin matsa lamba load a kan surface a mayar da martani ga Laser ablation.Consequently, da ja iri muhimmanci karkatar da partemetry, musamman kusa da goyon bayan da bakin ciki structural stractural a cikin Laser sakamakon a cikin wani bakin ciki structural ramummuka a cikin Laser. agate daga saman zuwa ga substrate.Domin samun cikakkun bayanai masu ƙididdigewa game da damuwa na gida da rarrabawa, ana yin simintin mesoscopic na matsalar nakasar nakasa da aka haɗa zuwa zafi da canja wurin taro.
Matsayin da ke da iko na samfurin ya hada da (1) Matsakaicin Canja wurin Zuwa inda kake da yanayin da ake ciki da yanayin ƙasa, (2) Matsayi Lissafi na gwaji ya ƙunshi yanayin musayar yanayi da kuma expecicy Matsayi mai gudana.The mespx an bayyana shi dangane da lissafin matsa lamba na mannewar jiki.for Nomainfin ikon {hz} rubutu {hzari} rubutu {hz} ~ 200 ~ \ UPMU \ rubutu {m} \ \) na diamita mai inganci.
Hoto na 3 yana nuna sakamakon simintin lambobi na yankin narkakkar ta amfani da samfurin lissafi na macroscopic.The diamita na fusion zone ne \ (200~\upmu \ rubutu {m} \) (\ (100~\upmu \ rubutu {m} \) radius) da kuma \ (40 ~ \ upmu \ 0 pmu \ rubutu {m sim} \) da kuma \ (40 ~ \ upmu \ rubutu {m sim} \) da kuma \ (40 ~ \ upmu \ rubutu lokaci \ m \) sakamako na gida. t {K} \) saboda high intermittent factor na bugun jini modulation.The dumama \ (V_h \) da sanyaya \ (V_c \) rates ne a kan tsari na \ (10 ​​^ 7 \) da \ (10 ​​^ 6 ~ \ rubutu {K} / \ rubutu {s} \ ), bi da bi .Wadannan dabi'u suna da kyau yarjejeniya tare da mu na baya na analysis \ (V) da kuma 6.V = (V) da bincike da suka gabata. yana haifar da saurin zafi na saman Layer, inda ƙaddamarwar thermal zuwa substrate bai isa don cire zafi ba.Saboda haka, a \ (t=26 ~\upmu \ rubutu {s} \) zafin jiki na saman ya kai kamar yadda \ (4800 ~\ rubutu {K})) .Tsarin ƙaƙƙarfan ƙaƙƙarfan ƙaƙƙarfan kayan zai iya haifar da samfurin saman da za a iya jujjuya matsa lamba mai yawa.
Sakamakon kwaikwaiyo na lambobi na yankin narkewa na ƙwayar bugun jini guda ɗaya a kan 316L samfurin samfurin.Lokacin daga farkon bugun jini zuwa zurfin tafkin narkakkar da ya kai matsakaicin darajar shine \ (180 ~ \ upmu \ rubutu {s} \) . The isotherm \ (T = T_L = 1723 ~\ rubutu tsakanin ruwa da ruwa) lokaci (K}) wakilta. zuwa yawan damuwa da aka lasafta a matsayin aiki na zafin jiki a cikin sashe na gaba.Saboda haka, a cikin yanki tsakanin isolines guda biyu (isotherms \ (T = T_L \) da isobars \ (\ sigma = \ sigma _V (T) \)) ), lokaci mai ƙarfi yana ƙarƙashin nauyin nauyin inji mai ƙarfi, wanda zai iya haifar da canje-canje a cikin microstructure.
An kara bayanin wannan tasirin a cikin Hoto 4a, inda aka tsara matakin matsa lamba a cikin yanki na zube a matsayin aiki na lokaci da nisa daga saman. Na farko, yanayin matsa lamba yana da alaƙa da daidaitawar ƙarfin bugun jini na laser da aka kwatanta a cikin Hoto na 2 a sama. Matsakaicin matsa lamba \ rubutu {s} \) na game da \ (10 ​​~\ rubutu {MPa} \) an lura da matsa lamba na gida a game da (ctu) a kusa da mu. batu yana da halaye na oscillation iri ɗaya kamar mita na \ (500 ~ \ rubutu {kHz} \) . Wannan yana nufin cewa ana haifar da raƙuman ruwa na ultrasonic a saman sannan kuma ya yada cikin substrate.
Abubuwan da aka ƙididdigewa na yankin nakasawa kusa da yankin narkewa ana nuna su a cikin siffa 4b. Laser ablation da thermoelastic danniya suna haifar da raƙuman ruwa na nakasa wanda ke yadawa a cikin substrate. Kamar yadda za'a iya gani daga adadi, akwai matakai guda biyu na ƙaddamar da damuwa. A lokacin farkon lokaci na \ (t <40~\upmu \ rubutu {s}\), da {8 MP na matsa lamba zuwa matsa lamba [8]. .Wannan damuwa yana faruwa ne saboda ablation na laser, kuma ba a lura da damuwa na thermoelastic a cikin wuraren sarrafawa ba saboda farkon yanayin zafi mai zafi yana da ƙananan ƙananan. Lokacin da zafi ya ɓace a cikin ma'auni, ma'anar sarrafawa yana haifar da matsananciyar thermoelastic sama da \ (40 ~ \ rubutu {MPa} \).
Matsakaicin matakan da aka daidaita da aka samu suna da tasiri mai mahimmanci akan ƙayyadaddun ruwa mai ƙarfi kuma yana iya zama tsarin sarrafawa wanda ke jagorantar hanyar ƙaddamarwa. Girman girman yankin nakasar shine 2 zuwa 3 sau girma fiye da na yankin narkewa. Kamar yadda aka nuna a cikin Hoto 3, wurin da ke narkewa da isotherm mai narkewa da kuma matakin damuwa daidai da yawan karuwar yawan damuwa ana kwatanta. mu \rubutu {m}\) ya danganta da lokacin nan take.
Saboda haka, da hadaddun daidaitawa na pulsed Laser annealing take kaiwa zuwa ultrasonic sakamako.The microstructure selection hanya ne daban-daban idan idan aka kwatanta da SLM ba tare da ultrasonic loading.Deformed m yankunan kai ga lokaci-lokaci hawan keke na matsawa da kuma mikewa a cikin m phase.Saboda haka, samuwar sabon hatsi iyakoki da subgrain iyakoki zama m kamar yadda microstructure iyakoki ya zama mai yiwuwa ya zama m. don tsara nau'in nau'in nau'in nau'in nau'in bugun jini wanda aka haifar da duban dan tayi na SLM.
(a) Matsi a matsayin aikin lokaci, ƙididdigewa a nisa daban-daban daga saman 0, 20 da \ (40 ~\upmu \ rubutu {m} \) tare da axis na daidaitawa.
An yi gwaje-gwaje akan faranti na bakin karfe na AISI 321H tare da ma'auni \ (20 \ sau 20 \ sau 5 ~ \ rubutu {mm} \ ). don haifar da remelting na kayan da aka sarrafa don gyaran ƙwayar hatsi.A duk lokuta, yankin remelted ya kasance sonicated, dangane da oscillatory bangaren na Laser radiation.Wannan yana haifar da raguwa fiye da sau 5 a matsakaicin hatsi. Hoto na 5 ya nuna yadda microstructure na yankin Laser-melted ya canza tare da adadin sake zagayowar remelting na gaba (wucewa).
Matsakaicin ra'ayi (a, d, g, j) da (b,e,h,k) - microstructure na yankuna na Laser narke, raƙuman ruwa (c, f, i,l) - rarraba yanki na hatsi masu launi.Shading yana wakiltar barbashi da aka yi amfani da su don ƙididdige histogram. Launuka sun dace da yankunan hatsi (duba sandar launi a saman tarihin tarihin. Subplots (ac) yayi daidai da bakin karfe da ba a kula da shi ba, kuma subplots (df), (gi), (jl) ya dace da 1, 3 da 5 remelts.
Tun da makamashin bugun jini na laser ba ya canzawa tsakanin wucewar da ke gaba, zurfin yankin narkakkar daidai yake. Saboda haka, tashar ta gaba ta gaba daya "ya rufe" na baya. Duk da haka, histogram ya nuna cewa ma'ana da tsaka-tsakin hatsi suna raguwa tare da karuwar adadin wucewa. Wannan yana iya nuna cewa laser yana aiki a kan substrate maimakon narke.
Ana iya haifar da tsaftacewar hatsi ta hanyar saurin kwantar da ruwa na narke65. Wani saitin gwaje-gwajen da aka gudanar a cikin abin da saman na bakin karfe faranti (321H da 316L) aka fallasa zuwa ci gaba da kalaman Laser radiation a cikin yanayi (Fig. 6) da kuma injin (Fig. 7) Matsakaicin ikon Laser (300 W da girmamawa 100) G sakamakon gwajin Laser na kusa da N. a cikin yanayin gudana kyauta.Duk da haka, an lura da tsarin ginshiƙi na al'ada.
Microstructure na Laser-narke yankin na ci gaba da igiyar Laser (300 W m iko, 200 mm / s scan gudun, AISI 321H bakin karfe).
(a) Microstructure da (b) electron backscatter diffraction hotuna na Laser-narke yankin a cikin injin daskarewa tare da ci gaba da kalaman Laser (100 W m iko, 200 mm / s scan gudun, AISI 316L bakin karfe) \ (\ SIM 2 ~ \ rubutu {mbar} \).
Saboda haka, an nuna a fili cewa hadaddun daidaitawa na Laser bugun jini tsanani yana da gagarumin tasiri a kan sakamakon microstructure.We yi imani da cewa wannan sakamako ne na inji a cikin yanayi da kuma faruwa saboda da ƙarni na ultrasonic vibrations propagating daga irradiated surface na narke zurfin cikin sample.Similar sakamakon da aka samu a 13, 26, 34, 66, 67 amfani da waje transducer transducer transducer da transduce transducer a cikin samfurin. 6Al-4V gami 26 da bakin karfe 34 sakamakon. A yiwu inji ne speculated kamar haka.M duban dan tayi na iya haifar da acoustic cavitation, kamar yadda aka nuna a cikin ultrafast a wurin synchrotron X-ray imaging.The rushewar cavitation kumfa bi bi da bi ya haifar da girgiza taguwar ruwa a cikin narkakkar kayan game da \ (text 10es). mai ƙarfi isa don haɓaka samuwar m-sized m-lokaci tsakiya a cikin ruwa mai yawa, rushe da hankula columnar hatsi tsarin Layer-by-Layer ƙari masana'antu.
Anan, muna ba da shawarar wani inji da ke da alhakin gyare-gyaren tsarin ta hanyar sonication mai tsanani. Nan da nan bayan ƙarfafawa, kayan abu yana a babban zafin jiki kusa da wurin narkewa kuma yana da ƙananan ƙananan yawan amfanin ƙasa.Intense ultrasonic taguwar ruwa na iya haifar da kwararan filastik don canza tsarin hatsi na zafi, kawai kayan da aka ƙera. Duk da haka, bayanan gwaji masu dogara akan yanayin da ake dogara da zafin jiki na dogara da yawan zafin jiki ba su samuwa a \ (T Figure 0) . fore, don gwada wannan hasashe, mun yi simulations na kwayoyin halitta (MD) na Fe-Cr-Ni abun da ke ciki kamar AISI 316 L karfe don kimanta halin danniya na yawan amfanin ƙasa kusa da wurin narkewa. Don ƙididdige yawan damuwa na yawan amfanin ƙasa, mun yi amfani da fasaha na kwantar da hankali na MD daki-daki a cikin 70, 71, 72, 73. Domin lissafin da aka yi amfani da shi a cikin Model 74. An yi amfani da simintin MD ta amfani da lambobin LAMMPS na 75,76. Za a buga cikakkun bayanai game da simintin MD a wasu wurare. Ana nuna sakamakon lissafin MD na yawan damuwa a matsayin aikin zafin jiki a cikin siffa 8 tare da bayanan gwaji na samuwa da sauran kimantawa77,78,79,80,81,82.
Samar da danniya don AISI aji 316 austenitic bakin karfe da samfurin abun da ke ciki tare da zafin jiki don MD simulations.Gwargwadon ma'auni daga nassoshi: (a) 77, (b) 78, (c) 79, (d) 80, (e) 81. koma zuwa.(f)82 ne wani empirical-nau'in naúrar dogara danniya-line sakamakon danniya-sakamako dogara danniya. na manyan sikelin MD a cikin wannan binciken ana nuna su a matsayin \ (\ vartriangleleft \) don kristal mara iyaka mara lahani mara lahani da \ (\ vartriangleright \) don ƙima mai iyaka la'akari da matsakaicin girman hatsi ta hanyar Hall-Petch Relation Dimensions \ (d = 50 ~ \ upmu \ rubutu {m} \).
Ana iya ganin cewa a \ (T> 1500 ~\ rubutu {K} \) yawan yawan amfanin ƙasa yana raguwa a ƙasa \ (40 ~\ rubutu {MPa} \) . A gefe guda, ƙididdiga sun yi la'akari da cewa hasken ultrasonic da aka haifar da Laser ya wuce \ (40 ~\ rubutu {MPa} \) (duba siffa 4b), wanda ya isa ya haifar da ingantaccen filastik.
Samuwar microstructure na 12Cr18Ni10Ti (AISI 321H) bakin karfe austenitic a lokacin SLM an bincika ta hanyar gwaji ta amfani da madaidaicin ƙarfin-modulated tushen Laser.
An sami raguwar girman hatsi a yankin narkewar Laser saboda ci gaba da sake narkewar Laser bayan wucewar 1, 3 ko 5.
Macroscopic yin tallan kayan kawa ya nuna cewa kiyasin girman yankin inda nakasar ultrasonic na iya tasiri ga ingantaccen gaba har zuwa \(1~\rubutu {mm}\).
Ƙimar MD mai ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun kayan aiki na AISI 316 austenitic bakin karfe yana raguwa sosai zuwa \ (40 ~ \ rubutu {MPa} \) kusa da wurin narkewa.
Sakamakon da aka samu ya ba da shawarar wata hanya don sarrafa microstructure na kayan ta amfani da hadaddun sarrafa Laser mai daidaitawa kuma zai iya zama tushen don ƙirƙirar sabbin gyare-gyare na dabarar SLM mai pulsed.
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