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Tsangwama ta Laser kai tsaye (DLIP) haɗe tare da Laser-induced periodic surface tsarin (LIPSS) yana ba da damar ƙirƙirar saman aiki don abubuwa daban-daban.Abubuwan da ake amfani da su na tsari yawanci suna karuwa ta amfani da matsakaicin matsakaicin ƙarfin laser.Duk da haka, wannan yana haifar da tarin zafi, wanda ke rinjayar rashin ƙarfi da siffar yanayin da aka samu.Sabili da haka, ya zama dole a yi nazari dalla-dalla game da tasirin zafin jiki na substrate akan yanayin halittar abubuwan da aka ƙirƙira.A cikin wannan binciken, an tsara saman karfen layi tare da ps-DLIP a 532 nm.Don bincika tasirin zafin jiki a kan yanayin da aka samu, an yi amfani da farantin dumama don sarrafa zafin jiki.Dumama zuwa 250 \(^{\circ}\)C ya haifar da raguwa mai yawa a cikin zurfin sifofin da aka kafa daga 2.33 zuwa 1.06 µm.Ragewar yana da alaƙa da bayyanar nau'ikan LIPSS daban-daban dangane da daidaitawar hatsin ƙasa da iskar oxygen da ke haifar da laser.Wannan binciken yana nuna tasiri mai ƙarfi na zafin jiki na substrate, wanda kuma ana tsammanin lokacin da ake yin jiyya a saman a matsakaicin matsakaicin ikon laser don ƙirƙirar tasirin tara zafi.
Hanyoyin jiyya na saman da ke kan ultrashort pulse laser irradiation suna kan gaba a fannin kimiyya da masana'antu saboda iyawar su na inganta abubuwan da suka fi dacewa da kayan da suka dace1.A musamman, Laser-jawo al'ada surface ayyuka ne jihar-na-da-art fadin wani fadi da kewayon masana'antu sassa da aikace-aikace al'amuran1,2,3.Alal misali, Vercillo et al.An nuna kaddarorin anti-kankara akan alloys titanium don aikace-aikacen sararin samaniya dangane da superhydrophobicity mai haifar da laser.Epperlein et al ya ruwaito cewa nanosized siffofin samar da Laser surface structuring zai iya rinjayar biofilm girma ko hanawa a kan karfe samfurin5.Bugu da kari, Guai et al.Hakanan ya inganta kaddarorin gani na kwayoyin halitta na hasken rana.6 Don haka, tsarin laser yana ba da damar samar da abubuwa masu ƙarfi masu ƙarfi ta hanyar sarrafa ablation na kayan saman1.
A dace Laser structuring dabara don samar da irin wannan lokaci-lokaci surface Tsarin ne kai tsaye Laser tsangwama siffata (DLIP).DLIP ya dogara ne akan tsangwama kusa-kusa na katakon Laser biyu ko fiye don samar da filaye masu ƙima tare da halaye a cikin kewayon micrometer da nanometer.Ya danganta da lamba da polarization na katako na Laser, DLIP na iya ƙirƙira da ƙirƙirar nau'ikan sifofi iri-iri.Hanya mai ban sha'awa ita ce haɗa tsarin DLIP tare da Laser-induced periodic surface structures (LIPSS) don ƙirƙirar saman hoto tare da sarkar tsarin tsari8,9,10,11,12.A cikin dabi'a, an nuna waɗannan jagororin don samar da mafi kyawun aiki fiye da ƙirar sikeli ɗaya13.
Ayyukan LIPSS yana ƙarƙashin tsari na haɓaka kai (tabbatacciyar amsa) dangane da haɓakar yanayin kusa-kusa na rarraba ƙarfin radiation.Wannan shi ne saboda karuwa a cikin nanoroughness yayin da adadin ƙwayar laser da aka yi amfani da shi ya karu 14, 15, 16. Modulation yana faruwa ne musamman saboda tsangwama na igiyoyin da aka fitar tare da filin lantarki15,17,18,19,20,21 na refracted da tarwatsa abubuwan raƙuman ruwa ko plasmons na saman.Samuwar LIPSS kuma yana shafar lokacin bugun bugun jini22,23.Musamman, matsakaicin matsakaicin ƙarfin Laser yana da makawa don jiyya na saman yawan aiki.Wannan yawanci yana buƙatar amfani da ƙimar maimaitawa mai yawa, watau a cikin kewayon MHz.Saboda haka, lokacin nisa tsakanin bugun jini na Laser ya fi guntu, wanda ke haifar da tasirin tarawar zafi 23, 24, 25, 26. Wannan tasirin yana haifar da haɓaka gabaɗaya a yanayin zafin jiki, wanda zai iya tasiri sosai ga tsarin ƙirar a lokacin ablation na laser.
A cikin aikin da ya gabata, Rudenko et al.da Tzibidis et al.An tattauna hanyar samar da sifofi masu ɗaukar hoto, wanda yakamata ya zama mai mahimmanci yayin da tarin zafi ya karu19,27.Bugu da ƙari, Bauer et al.Daidaita mahimmancin adadin tarin zafi tare da sifofi na micron.Duk da wannan tsari na samar da yanayin zafi, an yi imani da cewa za a iya inganta yawan aiki ta hanyar ƙara yawan maimaitawa28.Ko da yake wannan, bi da bi, ba za a iya samu ba tare da wani gagarumin karuwa a cikin zafi ajiya.Don haka, dabarun tsari waɗanda ke ba da ilimin topology da yawa ƙila ba za su iya ɗaukar nauyi zuwa ƙimar maimaitawa mafi girma ba tare da canza tsarin motsi da haɓakar tsari9,12.Dangane da wannan, yana da matukar muhimmanci a bincika yadda yanayin zafin jiki ke shafar tsarin samar da DLIP, musamman lokacin yin sifofi mai yadudduka saboda samuwar LIPSS a lokaci guda.
Manufar wannan binciken shine don kimanta tasirin yanayin zafin jiki akan sakamakon saman saman yayin sarrafa DLIP na bakin karfe ta amfani da ps pulses.A lokacin sarrafa Laser, an kawo zafin jiki na samfurin samfurin har zuwa 250 \ (^\circ \) C ta amfani da farantin dumama.Abubuwan da aka haifar an siffanta su ta hanyar amfani da microscopy mai kamanni, duban sinadarai na lantarki, da hasken hasken X-ray mai tarwatsa makamashi.
A cikin jerin gwaje-gwajen farko, an sarrafa ma'aunin karfe ta hanyar amfani da tsarin DLIP mai katako guda biyu tare da lokacin sararin samaniya na 4.5 µm da zafin jiki na substrate na \(T_{\mathrm {s}}\) 21 \(^{\circ). }\)C, daga nan ana kiranta da “babu mai zafi”.A wannan yanayin, pulse overlap \(o_{\mathrm {p}}\) shine nisa tsakanin bugun jini guda biyu a matsayin aikin girman tabo.Ya bambanta daga 99.0% (100 bugun jini a kowane matsayi) zuwa 99.67% (300 bugun jini a kowane matsayi).A duk lokuta, an yi amfani da mafi girman ƙarfin kuzari \ (\Phi _ \ mathrm {p} \) = 0.5 J/cm \ (^ 2 \) (na Gaussian daidai ba tare da tsangwama ba) da maimaita mita f = 200 kHz.Jagoran polarization na katako na Laser yana daidai da motsi na tebur na sakawa (Fig. 1a)), wanda yake daidai da jagorancin ma'auni na linzamin kwamfuta wanda aka kirkiro ta hanyar tsoma baki biyu.Hotunan wakilci na sigar da aka samu ta amfani da na'urar duba microscope (SEM) ana nuna su a cikin Fig.1 a-c ku.Don tallafawa nazarin hotuna na SEM dangane da yanayin yanayi, Fourier transforms (FFTs, wanda aka nuna a cikin duhu duhu) an yi a kan tsarin da ake kimantawa.A duk lokuta, sakamakon lissafin DLIP yana bayyane tare da lokacin sarari na 4.5 µm.
Don shari'ar \ (o_{\mathrm {p}} \) = 99.0% a cikin duhu mafi duhu na siffa.1a, daidai da matsayi na matsakaicin tsangwama, wanda zai iya lura da ramukan da ke dauke da ƙananan sifofi masu kama da juna.Suna musanya tare da maɗaura masu haske waɗanda aka rufe a cikin hoto mai kama da nanoparticle.Domin tsarin layi daya da ke tsakanin tsagi ya bayyana yana da tsayin daka ga polarization na katako na Laser kuma yana da tsawon lokaci na \(\Lambda _{\mathrm {LSFL-I}} \) 418 \ (\pm 65 \) nm, dan kadan. kasa da tsawon zangon laser \ (\lambda \) (532 nm) ana iya kiransa LIPSS tare da ƙananan mitar sarari (LSFL-I) 15,18.LSFL-I yana samar da abin da ake kira siginar nau'in s a cikin FFT, "s" watsawa15,20.Saboda haka, siginar tana tsaye ne da ƙaƙƙarfan sigar tsakiya mai ƙarfi, wanda kuma tsarin DLIP ke haifar da shi (\(\Lambda _{\mathrm {DLIP}}\) \(\kimanin\) 4.5 µm).Siginar da aka samar ta hanyar layin layi na tsarin DLIP a cikin hoton FFT ana kiransa "nau'in DLIP".
Hotunan SEM na tsarin saman da aka ƙirƙira ta amfani da DLIP.Mafi girman ƙarfin kuzari shine \ (\Phi _ \ mathrm {p} \) = 0.5 J/cm \ (^ 2 \) (don amo Gaussian daidai) da ƙimar maimaita f = 200 kHz.Hotunan suna nuna yanayin zafin samfurin, polarization da mai rufi.Motsin yanayin yanki yana da alamar baƙar kibiya a cikin (a).Baƙar fata yana nuna daidai FFT da aka samu daga 37.25 \ (\ times \) 37.25 µm SEM image (wanda aka nuna har sai wavector ya zama \ (\vec {k}\cdot (2\pi) ^ {-1} \) = 200 nm).Ana nuna sigogin tsari a kowane adadi.
Duba cikin Hoto na 1, zaku iya ganin cewa yayin da \(o_{\mathrm {p}}\) ke ƙaruwa, siginar sigmoid ya fi karkata zuwa ga axis na FFT.Sauran LSFL-I sun fi dacewa su zama daidai da juna.Bugu da ƙari, ƙarfin dangi na siginar nau'in s ya ragu kuma ƙarfin siginar nau'in DLIP ya karu.Wannan ya faru ne saboda ƙara furta ramuka tare da ƙarin zoba.Har ila yau, siginar x-axis tsakanin nau'in s da cibiyar dole ne ta fito daga tsarin da ke da tsari iri ɗaya da LSFL-I amma tare da tsawon lokaci (\ (\Lambda _ \ mathrm {b} \) \ (\kimanin \ ) 1.4 ± 0.2 µm) kamar yadda aka nuna a hoto 1c).Saboda haka, ana zaton samuwarsu wani tsari ne na ramuka a tsakiyar ramin.Hakanan sabon fasalin yana bayyana a cikin babban kewayon mitar (babban lambar igiyar ruwa) na ordinate.Siginar ta fito ne daga ripples a kan gangara na ramuka, mai yuwuwa saboda tsoma bakin abin da ya faru da haske mai nuna gaba akan gangara9,14.A cikin masu biyowa, LSFL \ (_ \ mathrm {edge} \) ne ke bayyana waɗannan ripples, da siginoninsu - ta nau'in -s \ (_ {\mathrm {p)) \).
A cikin gwaji na gaba, an kawo yawan zafin jiki na samfurin har zuwa 250 ° C a ƙarƙashin abin da ake kira "mai zafi".An gudanar da tsari bisa ga dabarun sarrafawa iri ɗaya kamar gwaje-gwajen da aka ambata a cikin sashe na baya (Figs. 1a-1c).Hotunan SEM suna nuna sakamakon da aka samu kamar yadda aka nuna a hoto. 1d-f.Dumama samfurin zuwa 250 C yana haifar da karuwa a cikin bayyanar LSFL, jagorancin wanda yake daidai da polarization laser.Ana iya siffanta waɗannan sifofin azaman LSFL-II kuma suna da lokacin sarari \(\Lambda _\mathrm {LSFL-II}\) na 247 ± 35 nm.Ba a nuna siginar LSFL-II a cikin FFT saboda babban mitar yanayi.Kamar yadda \ (o_{\mathrm {p}} \) ya karu daga 99.0 zuwa 99.67 \ (\% \) (Fig. 1d-e), nisa na yanki mai haske ya karu, wanda ya haifar da bayyanar siginar DLIP. don fiye da manyan mitoci.lambobi (ƙananan mitoci) don haka matsawa zuwa tsakiyar FFT.Layukan ramuka a cikin siffa 1d na iya zama mafarin abubuwan da ake kira ramukan da aka kafa daidai da LSFL-I22,27.Bugu da ƙari, LSFL-II ya bayyana ya zama guntu kuma ba a tsara su ba.Lura kuma cewa matsakaicin girman maɗaukaki masu haske tare da ilimin halittar nanograin ya fi ƙanƙanta a wannan yanayin.Bugu da kari, girman rarraba wadannan nanoparticles ya juya ya zama ƙasa da tarwatsewa (ko haifar da ƙarancin barbashi agglomeration) fiye da ba tare da dumama ba.A cikin inganci, ana iya tantance wannan ta hanyar kwatanta adadi 1a, d ko b, e, bi da bi.
Yayin da haɗin gwiwar \(o_{\mathrm {p}}) ya ƙaru zuwa 99.67% (Fig. 1f), wani yanayi na musamman ya bayyana a hankali saboda ƙara fitowa fili.Koyaya, waɗannan tsagi suna bayyana ƙasa da oda kuma ƙasa da zurfi fiye da siffa 1c.Ƙananan bambanci tsakanin haske da wuraren duhu na hoton yana nunawa cikin inganci.Waɗannan sakamakon suna ƙara goyan bayan sigina mafi rauni kuma mafi tarwatsawa na FFT ordinate a cikin siffa 1f idan aka kwatanta da FFT akan c.Ƙananan striae kuma sun bayyana akan dumama lokacin da aka kwatanta Figures 1b da e, wanda aka tabbatar da shi ta hanyar microscopy.
Baya ga gwajin da ya gabata, an jujjuya polarization na katako na Laser da 90 \(^{\circ}\), wanda ya sa jagoran polarization ya matsa daidai da dandamalin sakawa.A kan fig.2a-c yana nuna farkon matakan samar da tsari, \(o_{\mathrm {p}}\) = 99.0% a cikin unheated (a), mai tsanani (b) da zafi 90 \ (^{\ cir }\ ) - Case tare da juyawa polarization (c).Don ganin nanotopography na sifofi, ana nuna wuraren da aka yi alama da murabba'i masu launi a cikin ɓangarorin.2d, akan ma'auni mai girma.
Hotunan SEM na tsarin saman da aka ƙirƙira ta amfani da DLIP.Siffofin tsari iri ɗaya ne kamar yadda yake a cikin Fig.1.Hoton yana nuna samfurin zafin jiki \(T_s \), polarization da pulse overlap \(o_\mathrm {p}\).Saitin baki yana sake nuna madaidaicin canjin Fourier.Hotunan cikin (d)-(i) girman wuraren da aka yiwa alama a (a)-(c).
A wannan yanayin, ana iya ganin cewa tsarin da ke cikin wurare masu duhu na Fig. 2b, c suna da mahimmanci na polarization kuma saboda haka an lakafta su LSFL-II14, 20, 29, 30. Musamman ma, daidaitawar LSFL-I kuma yana juyawa ( Hoto 2g, i), wanda za'a iya gani daga madaidaicin siginar nau'in s a cikin FFT daidai.Yawan bandwidth na lokacin LSFL-I ya bayyana ya fi girma idan aka kwatanta da lokacin b, kuma ana jujjuya kewayon zuwa ƙananan lokuta a cikin siffa.Don haka, ana iya lura da lokacin sararin samaniya na LSFL mai zuwa akan samfurin a yanayin zafi daban-daban: \ (\Lambda _{\mathrm {LSFL-I}} \) = 418 \ (\ pm 65 \) nm a 21 ^{ \circ. }\ )C (Fig. 2a), \(\Lambda _{\mathrm {LSFL-I}} \) = 445\(~\pm\) 67 nm da \(\Lambda _{\mathrm {LSFL-II }} \) = 247 ± 35 nm a 250 ° C (Fig. 2b) don s polarization.Akasin haka, lokacin sararin samaniya na p-polarization da 250 \(^{\circ }\)C daidai yake da \(\Lambda _{\mathrm {LSFL-I)) \) = 390\(\pm 55\) ) nm da \(\ Lambda_{\mathrm{LSFL-II}}\) = 265±35 nm (Fig. 2c).
Musamman ma, sakamakon ya nuna cewa kawai ta hanyar ƙara yawan zafin jiki na samfurin, yanayin yanayin yanayi na iya canzawa tsakanin matsananci biyu, gami da (i) saman da ke ɗauke da abubuwan LSFL-I kawai da (ii) yanki da aka rufe da LSFL-II.Saboda samuwar wannan nau'in LIPSS na musamman akan saman ƙarfe yana da alaƙa da shimfidar oxide na saman, an gudanar da binciken binciken X-ray na makamashi (EDX).Table 1 yana taƙaita sakamakon da aka samu.Ana aiwatar da kowace ƙaddara ta matsakaicin aƙalla baƙaƙe huɗu a wurare daban-daban akan saman samfurin da aka sarrafa.Ana yin ma'auni a yanayin yanayin samfuri daban-daban \(T_\mathrm{s}\) da wurare daban-daban na saman samfurin da ke ɗauke da wuraren da ba a tsara su ba.Hakanan ma'aunin yana ƙunshe da bayanai game da zurfin yadudduka marasa ƙarfi waɗanda ke kwance kai tsaye ƙasa da narkakken yanki, amma a cikin zurfin shigar da lantarki na binciken EDX.Duk da haka, ya kamata a lura cewa EDX yana da iyaka a cikin ikonsa na ƙididdige abubuwan da ke cikin oxygen, don haka waɗannan dabi'u a nan za su iya ba da ƙima mai mahimmanci kawai.
Abubuwan da ba a kula da su ba na samfuran ba su nuna adadin iskar oxygen a duk yanayin yanayin aiki ba.Bayan maganin Laser, matakan oxygen ya karu a duk lokuta31.Bambanci a cikin abun da ke ciki tsakanin samfuran biyu da ba a kula da su ba kamar yadda ake tsammani don samfuran ƙarfe na kasuwanci, kuma an sami ƙimar ƙimar carbon mafi girma idan aka kwatanta da takaddar bayanan masana'anta don karfe AISI 304 saboda gurɓataccen hydrocarbon32.
Kafin yin magana akan dalilai masu yuwuwa na raguwar zurfin zurfin tsagi da kuma sauyawa daga LSFL-I zuwa LSFL-II, ana amfani da girman girman ikon (PSD) da bayanan martaba.
(i) Matsakaicin girman girman girman girman girman girman girman (Q2D-PSD) na saman an nuna shi azaman hotunan SEM a cikin Figures 1 da 2. 1 da 2. Tun da PSD ya daidaita, raguwa a cikin siginar jimla ya kamata ya kasance. fahimta a matsayin karuwa a cikin madaidaicin sashi (k \ (\ le \) 0.7 µm \ (^ {-1} \), ba a nuna ba), watau santsi.(ii) Ma'anar ma'anar tsayin daka.Samfurin zafin jiki \(T_s \), zoba \(o_{\mathrm {p}}\), da kuma Laser polarization E dangane da fuskantarwa \(\vec {v}\) na matsawa dandali motsi ana nuna a duk filaye.
Don ƙididdige ra'ayi na hotunan SEM, an samar da matsakaicin matsakaicin matsakaicin ƙarfin bakan wutar lantarki daga aƙalla hotuna SEM guda uku don kowane sigina da aka saita ta matsakaicin duk girman girman girman girman (1D) (PSDs) a cikin x ko y.Ana nuna jadawali mai dacewa a cikin siffa 3i yana nuna mitar motsi na sigina da gudunmawar dangi zuwa bakan.
A kan fig.3ia, c, e, kololuwar DLIP yana girma kusa da \(k_{\mathrm {DLIP}}~=~2\pi\) (4.5 µm)\(^{-1}\) = 1.4 µm \ ( ^{- 1}\) ko madaidaicin jituwa mafi girma yayin da haɗin gwiwa ya ƙaru \(o_{\mathrm {p))\).Ƙaruwa a cikin mahimmancin mahimmanci yana da alaƙa da haɓaka mai ƙarfi na tsarin LRIB.Girman girman jituwa mafi girma yana ƙaruwa tare da steepness na gangara.Don ayyukan rectangular azaman iyakance lokuta, ƙimayar tana buƙatar mafi girman adadin mitoci.Saboda haka, kololuwar kusa da 1.4 µm \(^{-1}\) a cikin PSD da kuma daidaitattun jituwa za a iya amfani da su azaman ingantattun sigogi don siffar tsagi.
Akasin haka, kamar yadda aka nuna a cikin siffa 3 (i) b,d,f, PSD na samfurin mai zafi yana nuna mafi rauni da mafi girman kololuwa tare da ƙarancin sigina a cikin jituwa masu jituwa.Bugu da kari, a cikin fig.3(i)f yana nuna siginar jituwa na biyu har ma ya wuce siginar asali.Wannan yana nuna tsarin DLIP mafi rashin daidaituwa da ƙarancin furci na samfurin zafi (idan aka kwatanta da \ (T_s \) = 21 \ (^\circ \) C).Wani fasalin kuma shi ne cewa yayin da haɗin gwiwar \(o_{\mathrm {p}}\) ke ƙaruwa, sakamakon siginar LSFL-I yana motsawa zuwa ƙarami mai lamba (tsawon lokaci).Ana iya yin bayanin wannan ta hanyar ƙara girman gefuna na yanayin DLIP da haɓakar gida mai alaƙa a cikin kusurwar abin da ya faru14,33.Bayan wannan yanayin, ana iya bayyana faɗaɗa siginar LSFL-I.Bugu da ƙari ga gangaren gangaren, akwai kuma wurare masu faɗi a ƙasa da sama da ƙwanƙolin tsarin DLIP, suna ba da damar faffadan lokutan LSFL-I.Don kayan da ake sha sosai, ana ƙididdige lokacin LSFL-I kamar:
inda \(\theta\) shine kusurwar abin da ya faru, kuma rubutun s da p suna nufin polarizations daban-daban33.
Ya kamata a lura cewa jirgin da ke faruwa don saitin DLIP yawanci yana daidaitawa zuwa motsi na dandalin sakawa, kamar yadda aka nuna a cikin Hoto 4 (duba sashin Kayan aiki da Hanyoyi).Saboda haka, s-polarization, a matsayin mai mulkin, yana daidai da motsi na mataki, kuma p-polarization yana daidai da shi.Bisa ga lissafin.(1), don s-polarization, ana sa ran yaduwa da jujjuya siginar LSFL-I zuwa ƙananan lambobi.Wannan ya faru ne saboda haɓakar \ (\theta \) da kuma kewayon angular \ (\theta \ pm \ delta \ theta \) yayin da zurfin rami ya ƙaru.Ana iya ganin wannan ta hanyar kwatanta kololuwar LSFL-I a cikin siffa 3ia,c,e.
Bisa ga sakamakon da aka nuna a cikin fig.1c, LSFL \(_\mathrm {edge}\) kuma ana iya gani a cikin PSD mai dacewa a cikin fig.3ie.A kan fig.3ig, h yana nuna PSD don p-polarization.Bambanci a cikin kololuwar DLIP ya fi fitowa fili tsakanin samfurori masu zafi da marasa zafi.A wannan yanayin, siginar daga LSFL-I ya mamaye tare da mafi girman jituwa na kololuwar DLIP, ƙara zuwa siginar kusa da lasing wavelength.
Don tattauna sakamakon daki-daki, a cikin siffa 3ii yana nuna zurfin tsari da haɗuwa tsakanin bugun jini na rarraba tsayin madaidaiciyar DLIP a yanayin zafi daban-daban.An samo bayanin martaba na tsayin tsaye ta hanyar maƙasudi goma na daidaitattun bayanan martaba a tsaye kusa da tsakiyar tsarin DLIP.Ga kowane zafin jiki da aka yi amfani da shi, zurfin tsarin yana ƙaruwa tare da haɓaka bugun bugun jini.Bayanan martabar samfurin mai zafi yana nuna tsagi tare da ma'anar kololuwa zuwa ganiya (pvp) ƙimar 0.87 µm don s-polarization da 1.06 µm don p-polarization.Ya bambanta, s-polarization da p-polarization na samfurin unheated yana nuna pvp na 1.75 µm da 2.33 µm, bi da bi.An kwatanta pvp mai dacewa a cikin bayanin martaba mai tsayi a cikin fig.3ii.Ana ƙididdige kowane matsakaitan PvP ta matsakaicin PvP guda takwas.
Bugu da kari, a cikin fig.3iig, h yana nuna p-polarization tsawo rarraba perpendicular zuwa tsarin sakawa da tsagi motsi.Jagoran p-polarization yana da tasiri mai kyau akan zurfin tsagi tun lokacin da ya haifar da dan kadan mafi girma pvp a 2.33 µm idan aka kwatanta da s-polarization a 1.75 µm pvp.Wannan kuma ya dace da tsagi da motsi na tsarin dandamali na sakawa.Ana iya haifar da wannan tasiri ta hanyar ƙaramin tsari a cikin yanayin s-polarization idan aka kwatanta da yanayin p-polarization (duba siffa 2f, h), wanda za a tattauna gaba a cikin sashe na gaba.
Manufar tattaunawar ita ce bayyana raguwa a cikin zurfin tsagi saboda canji a cikin babban nau'in LIPS (LSFL-I zuwa LSFL-II) a cikin yanayin samfurori masu zafi.Don haka amsa tambayoyi kamar haka:
Don amsa tambaya ta farko, yana da muhimmanci a yi la'akari da hanyoyin da ke da alhakin raguwa a cikin ablation.Don bugun bugun jini guda ɗaya a al'ada ta al'ada, ana iya kwatanta zurfin zubar da ciki kamar:
inda \(\delta _{\mathrm {E}}\) shine zurfin shigar kuzari, \(\Phi \) da \(\Phi _{\mathrm {th}}) sune ƙwaƙƙwaran shaye-shaye da ƙwarewar Ablation kofa, bi da bi34 .
A ilimin lissafi, zurfin shigar makamashi yana da tasiri mai yawa akan zurfin zubar da ciki, yayin da canjin makamashi yana da tasirin logarithmic.Don haka canje-canjen magana ba sa shafar \(\Delta z\) matuƙar dai \(\Phi ~\gg ~Phi _{\mathrm {th}}\).Koyaya, iskar oxygen mai ƙarfi (misali, saboda samuwar chromium oxide) yana haifar da haɓakar haɗin gwiwar Cr-O35 idan aka kwatanta da haɗin gwiwar Cr-Cr, ta haka yana haɓaka kofa.Saboda haka, \(\Phi ~\gg ~\Phi _{\mathrm {th}}\) bai ƙara gamsuwa ba, wanda ke haifar da raguwa cikin sauri a cikin zurfin ɓarna tare da rage yawan ƙarfin kuzari.Bugu da ƙari, an san haɗin kai tsakanin yanayin iskar oxygen da lokacin LSFL-II, wanda za'a iya bayyana shi ta hanyar canje-canje a cikin nanostructure kanta da kuma abubuwan da ke cikin yanayin da ke haifar da oxidation30,35.Sabili da haka, ainihin rarraba sararin samaniya na shayarwa \ (\ Phi \) yana faruwa ne saboda hadaddun yanayin hulɗar tsakanin tsarin tsarin da kauri na Layer oxide.Dangane da lokacin, nanostructure yana da tasiri mai karfi akan rarraba wutar lantarki da aka sha saboda karuwa mai girma a cikin filin, tashin hankali na plasmons, canja wurin haske mai ban mamaki ko watsawa17,19,20,21.Saboda haka, \(\Phi \) ba shi da kamanni a kusa da saman, kuma \(\ delta _ {E} \) mai yiwuwa ba zai yiwu ba tare da ƙididdiga guda ɗaya \ (\alpha = \ delta _{\mathrm {opt}} ^ {-1} \kimanin \delta _{\mathrm {E}}^{-1}Tun da kauri na fim ɗin oxide ya dogara da yawa akan lokacin ƙarfafawa [26], tasirin nomenclature ya dogara da zafin samfurin.Micrographs na gani da aka nuna a cikin Hoto S1 a cikin Ƙarin Material suna nuna canje-canje a cikin abubuwan gani.
Waɗannan tasirin sun ɗan bayyana zurfin zurfin rami mai zurfi a cikin yanayin ƙananan sifofi a cikin Figures 1d,e da 2b,c da 3(ii)b,d,f.
LSFL-II an san shi don samarwa akan semiconductor, dielectrics, da kayan da ke da alaƙa da iskar shaka14,29,30,36,37.A cikin akwati na ƙarshe, kauri na saman oxide Layer yana da mahimmanci musamman30.Binciken EDX da aka gudanar ya nuna samuwar oxides na saman akan tsarin da aka tsara.Don haka, don samfurori marasa zafi, iskar oxygen na yanayi yana da alama yana ba da gudummawa ga samuwar gaseous barbashi da kuma samuwar saman oxides.Duka abubuwan mamaki suna ba da babbar gudummawa ga wannan tsari.Akasin haka, don samfurori masu zafi, ƙarfe oxides na jihohin oxidation daban-daban (SiO \ (_{\mathrm {2}}\), Cr \ (_{\mathrm {n}} \) O \ (_{\mathrm { m}}\ ), Fe \(_{\mathrm {n}}\)O\(_{\mathrm {m}}\), NiO, da dai sauransu) sun tabbata 38 sun yarda.Bugu da ƙari ga Layer oxide da ake buƙata, kasancewar rashin ƙarfi na subwavelength, galibi babban mitar sararin samaniya LIPSS (HSFL), ya zama dole don samar da yanayin ƙarfin da ake buƙata na subwavelength (d-type)14,30.Yanayin ƙarfin LSFL-II na ƙarshe aiki ne na girman girman HSFL da kauri oxide.Dalilin wannan yanayin shine tsangwama mai nisa na hasken da HSFL ya warwatse da hasken da ke jujjuyawa cikin kayan kuma yana yaduwa a cikin kayan dielectric surface20,29,30.Hotunan SEM na gefen ƙirar saman a cikin Hoto S2 a cikin Sashen Ƙarin Kayayyakin suna nuni ne na HSFL da aka rigaya.Wannan yanki na waje yana da rauni ta hanyar gefen rarraba ƙarfi, wanda ke ba da damar samuwar HSFL.Saboda ma'auni na rarraba ƙarfi, wannan tasirin kuma yana faruwa tare da hanyar dubawa.
Samfurin dumama yana shafar tsarin samuwar LSFL-II ta hanyoyi da yawa.A gefe ɗaya, haɓakar yanayin zafin samfurin \(T_\mathrm{s}\) yana da tasiri sosai akan ƙimar ƙarfafawa da sanyaya fiye da kauri na narkakken Layer26.Don haka, ƙirar ruwa na samfurin mai zafi yana nunawa ga oxygen na yanayi na tsawon lokaci.Bugu da kari, jinkirta solidification damar ci gaban hadaddun convective matakai da kara hadawa da oxygen da oxides da ruwa steel26.Ana iya nuna wannan ta hanyar kwatanta kauri na Layer oxide da aka kafa ta hanyar watsawa kawai (\(\Lambda _\mathrm {diff}=\sqrt{D~\times ~t_\mathrm {s}}~\le ~15\) nm) Madaidaicin lokacin coagulation ɗin shine \(t_\mathrm {s}~\le ~200\) ns, da kuma ma'aunin rarrabawa \(D~\le \) 10\(^{-5}\) cm\(^ 2 \ )/ s) An lura da kauri mai girma ko kuma ana buƙata a cikin tsarin LSFL-II30.A gefe guda, dumama kuma yana rinjayar samuwar HSFL kuma saboda haka abubuwan watsawa da ake buƙata don canzawa zuwa yanayin ƙarfin nau'in LSFL-II d.Bayyanar nanovoids tarko a ƙasa da saman yana nuna shigarsu cikin samuwar HSFL39.Waɗannan lahani na iya wakiltar asalin electromagnetic na HSFL saboda ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙarfi na lokaci-lokaci da ake buƙata14,17,19,29.Bugu da ƙari, waɗannan hanyoyin haɓakar ƙarfin sun fi daidaituwa tare da adadi mai yawa na nanovoids19.Don haka, ana iya bayyana dalilin karuwar HSFL ta hanyar canji a cikin sauye-sauye na lahani na crystal yayin da \(T_\mathrm{s}\) ke ƙaruwa.
Kwanan nan an nuna cewa adadin sanyaya na silicon shine maɓalli na maɓalli don haɓakawar tsaka-tsakin tsaka-tsaki don haka don tarin lahani tare da samuwar ɓarna40,41.Molecular Dynamic Simulations na tsarkakakken karafa sun nuna cewa guraben aiki sun yi yawa a lokacin saurin sake sakewa, don haka tarin guraben karafa ya samu ta irin wannan hanya42,43,44.Bugu da kari, binciken gwaji na baya-bayan nan na azurfa ya mayar da hankali kan tsarin samar da fanko da gungu saboda tarin lahani45.Sabili da haka, karuwa a cikin zafin jiki na samfurin \ (T_\mathrm {s}) kuma, saboda haka, raguwa a cikin adadin sanyaya zai iya rinjayar samuwar ɓoyayyen, wanda shine tsakiya na HSFL.
Idan guraben aiki sune abubuwan da suka zama dole ga cavities kuma saboda haka HSFL, zafin samfurin (T_s) yakamata ya sami tasiri biyu.A gefe ɗaya, \ (T_s \) yana rinjayar ƙimar sake sakewa kuma, saboda haka, ƙaddamar da lahani (matsawar sarari) a cikin crystal girma.A daya hannun, shi ma rinjayar da sanyaya kudi bayan solidification, game da shi rinjayar da yaduwa na batu lahani a cikin crystal 40,41.Bugu da ƙari, ƙimar ƙarfafawa ya dogara da yanayin daidaitawar crystallographic kuma don haka yana da anisotropic sosai, kamar yadda yake yaduwa na lahani42,43.Bisa ga wannan jigo, saboda amsawar anisotropic na abu, hulɗar haske da kwayoyin halitta sun zama anisotropic, wanda hakan yana kara girman wannan ƙaddamarwa na lokaci-lokaci na makamashi.Don kayan polycrystalline, ana iya iyakance wannan hali ta girman girman hatsi ɗaya.A haƙiƙa, an nuna samuwar LIPSS dangane da daidaitawar hatsi46,47.Saboda haka, tasirin samfurin zafin jiki \ (T_s \) akan ƙimar crystallization bazai da ƙarfi kamar tasirin daidaitawar hatsi.Don haka, madaidaicin crystallographic daban-daban na hatsi daban-daban yana ba da bayani mai yuwuwar haɓakar ɓarna da tarawar HSFL ko LSFL-II, bi da bi.
Don fayyace alamun farko na wannan hasashe, an ɗora samfuran danye don bayyana samuwar hatsi kusa da saman.Kwatanta hatsi a cikin fig.Ana nuna S3 a cikin ƙarin kayan.Bugu da ƙari, LSFL-I da LSFL-II sun bayyana a cikin ƙungiyoyi akan samfurori masu zafi.Girman da lissafi na waɗannan gungu sun dace da girman hatsi.
Bugu da ƙari, HSFL yana faruwa ne kawai a cikin kunkuntar kewayo a ƙananan ɗimbin ɗimbin yawa saboda madaidaicin asalin sa19,29,48.Sabili da haka, a cikin gwaje-gwaje, wannan mai yiwuwa yana faruwa ne kawai a gefen bayanin martaba.Sabili da haka, HSFL ya samo asali akan wuraren da ba a haɗa su ba ko rashin ƙarfi, wanda ya bayyana lokacin da aka kwatanta sassan oxide na samfuran da aka yi da magani da ba a kula da su ba (duba tebur reftab: misali).Wannan yana tabbatar da zato cewa layin oxide galibi yana haifar da laser.
Ganin cewa samuwar LIPSS yawanci ya dogara ne akan adadin bugun jini saboda ra'ayoyin tsaka-tsakin bugun jini, ana iya maye gurbin HSFLs da manyan sifofi yayin da bugun bugun jini ya karu19.Karancin HSFL na yau da kullun yana haifar da ƙarancin ƙima na yau da kullun (d-yanayin) da ake buƙata don samuwar LSFL-II.Saboda haka, yayin da haɗin gwiwar \ (o_\ mathrm {p}) ke ƙaruwa (duba siffa 1 daga de), daidaitawar LSFL-II yana raguwa.
Wannan binciken ya binciki tasirin yanayin zafin jiki akan yanayin yanayin halittar DLIP da aka tsara ta Laser da aka yi da bakin karfe.An gano cewa dumama substrate daga 21 zuwa 250 ° C yana haifar da raguwa a cikin zurfin ablation daga 1.75 zuwa 0.87 µm a cikin s-polarization kuma daga 2.33 zuwa 1.06 µm a cikin p-polarization.Wannan raguwar ta samo asali ne saboda canjin nau'in LIPSS daga LSFL-I zuwa LSFL-II, wanda ke da alaƙa da layin oxide saman da ke haifar da laser a mafi girman samfurin zazzabi.Bugu da ƙari, LSFL-II na iya ƙara yawan ƙofa saboda ƙarar iskar shaka.An ɗauka cewa a cikin wannan tsarin fasaha tare da babban bugun jini, matsakaicin ƙarfin ƙarfin kuzari da matsakaicin maimaitawa, abin da ya faru na LSFL-II kuma an ƙaddara shi ta hanyar canji a cikin sauye-sauyen yanayi wanda ya haifar da samfurin dumama.Tarin LSFL-II ana tsammanin ya kasance saboda haɓakar nanovoid mai dogaro da tsarin hatsi, wanda ke haifar da HSFL azaman mafari ga LSFL-II.Bugu da ƙari, ana nazarin tasirin jagorancin polarization akan tsarin tsarin da kuma bandwidth na lokacin tsarin.Ya bayyana cewa p-polarization ya fi dacewa ga tsarin DLIP dangane da zurfin ablation.Gabaɗaya, wannan binciken yana buɗe saitin sigogin tsari don sarrafawa da haɓaka zurfin DLIP don ƙirƙirar ƙirar saman da aka keɓance.A ƙarshe, sauyawa daga LSFL-I zuwa LSFL-II gabaɗayan zafi ne ke motsa shi kuma ana sa ran ƙaramin haɓakar maimaitawa tare da juzu'i na bugun jini akai-akai saboda haɓakar zafi24.Duk waɗannan abubuwan sun dace da ƙalubalen da ke tafe na faɗaɗa tsarin DLIP, misali ta hanyar amfani da na'urorin sikanin guda huɗu49.Don rage haɓakar zafi, ana iya bin dabarar da ke gaba: kiyaye saurin dubawa na na'urar daukar hotan takardu kamar yadda zai yiwu, yin amfani da girman girman tabo na Laser, kothogonal zuwa hanyar dubawa, da yin amfani da mafi kyawu.fluence 28. Bugu da ƙari, waɗannan ra'ayoyin suna ba da izinin ƙirƙirar ɗimbin yanayin yanayin matsayi don ci gaba da aikin shimfidar wuri ta amfani da DLIP.
A cikin wannan binciken, an yi amfani da faranti na bakin karfe (X5CrNi18-10, 1.4301, AISI 304) 0.8 mm kauri.Don cire duk wani gurɓataccen abu daga saman, an wanke samfuran a hankali tare da ethanol kafin maganin laser (cikakkiyar haɓakar ethanol \ (\ ge \) 99.9%).
Ana nuna saitin DLIP a Hoto na 4. An gina samfurori ta amfani da tsarin DLIP sanye take da tushen laser ultrashort 12 ps tare da tsayin tsayin 532 nm da matsakaicin adadin maimaitawa na 50 MHz.Rarraba sararin samaniya na makamashin katako shine Gaussian.Na'urorin gani na musamman da aka ƙera suna ba da ƙa'idar tsaka-tsakin tsaka-tsakin katako mai dual-beam don ƙirƙirar tsarin layi akan samfurin.Lens mai tsayi mai tsayin mm 100 yana ɗaukaka ƙarin ƙarin katakon Laser guda biyu akan saman a kafaffen kusurwa na 6.8 \(^\circ\), wanda ke ba da lokacin sararin samaniya kusan 4.5µm.Ana iya samun ƙarin bayani kan saitin gwaji a wani wuri50.
Kafin sarrafa Laser, ana sanya samfurin a kan farantin dumama a wani zazzabi.An saita zazzabi na farantin dumama a 21 da 250 ° C.A cikin dukkan gwaje-gwajen, an yi amfani da jet mai jujjuyawar iskar da aka matsa tare da na'urar shaye-shaye don hana shigar kura akan na'urorin gani.An saita tsarin matakin x,y don sanya samfurin yayin tsarawa.
Gudun tsarin matakin sakawa ya bambanta daga 66 zuwa 200 mm/s don samun zoba tsakanin bugun jini na 99.0 zuwa 99.67 \(\%\) bi da bi.A kowane hali, an daidaita ƙimar maimaitawa a 200 kHz, kuma matsakaicin ƙarfin shine 4 W, wanda ya ba da makamashi kowane bugun jini na 20 μJ.Diamita na katako da aka yi amfani da shi a cikin gwajin DLIP yana da kusan 100 µm, kuma sakamakon ƙarfin ƙarfin laser mafi girma shine 0.5 J/cm \(^{2}\).Jimillar makamashin da aka fitar a kowane yanki shine mafi girman iyawar da ta dace da 50 J/cm\(^2\) don \(o_{\mathrm {p}}\) = 99.0 \(\%\), 100 J/cm \(^2\) na \(o_{\mathrm {p))\)=99.5\(\%\) da 150 J/cm\(^2\) don \(o_{ \mathrm {p}}\) = 99.67 (\%).Yi amfani da farantin \(\lambda\)/2 don canza polarization na katako na Laser.Ga kowane saitin sigogin da aka yi amfani da shi, an rubuta yanki na kusan 35 × 5 mm\(^{2}\) akan samfurin.An gudanar da duk gwaje-gwajen da aka tsara a ƙarƙashin yanayin yanayi don tabbatar da aikin masana'antu.
An yi nazarin ilimin halittar jini na samfuran ta amfani da microscope mai ma'ana tare da haɓakar 50x da ƙuduri na gani da tsaye na 170 nm da 3 nm, bi da bi.Sannan an tantance bayanan da aka tattara ta hanyar amfani da software na tantance saman.Cire bayanan martaba daga bayanan ƙasa bisa ga ISO 1661051.
An kuma siffanta samfuran ta yin amfani da microscope na lantarki a saurin ƙarfin lantarki na 6.0kV.An kimanta nau'in sinadarai na saman samfuran ta amfani da abin da aka makala na X-ray spectroscopy (EDS) mai ƙarfi a ƙarfin ƙarfin lantarki na 15 kV.Bugu da kari, an yi amfani da na'urar gani da ido tare da maƙasudin 50x don tantance ƙayyadaddun ƙirar ƙirar ƙirar ƙirar ƙirar samfuran. Kafin wannan, samfuran an yi su ne a madaidaicin zafin jiki na 50 \ (^\circ\) C na tsawon mintuna biyar a cikin tabo bakin karfe tare da acid hydrochloric da ƙwayar nitric acid na 15-20 \ (\% \) da 1 \ ( -<\) 5 (\%\), bi da bi. Kafin wannan, samfuran an yi su ne a madaidaicin zafin jiki na 50 \ (^\circ\) C na tsawon mintuna biyar a cikin tabo bakin karfe tare da acid hydrochloric da ƙwayar nitric acid na 15-20 \ (\% \) da 1 \ ( -<\) 5 (\%\), bi da bi. Перед этиm obraztsy travyli при POSTOYAN TEMPERATURE 50 \(^\circ\) зотной кислотами концентрацией 15-20 \(\%\) и 1 \( -<\)5 \( \%\) sоответственно. Kafin wannan, samfuran an yi su ne a madaidaicin zafin jiki na 50 \ (^\circ \) C na minti biyar a cikin bakin karfe fenti tare da hydrochloric da acid nitric tare da maida hankali na 15-20 \ (\% \) da 1 \ ( - <\) 5 ( \% \) bi da bi.在此之前，样品在不锈钢染色液中以50 \(^\circ\)C 的恒温蚀刻五分钟，盐酸和硝酸 \(1) ) 5 \ (\%\), 分别.在此之前，样品在不锈钢染色液中以50 \(^\circ\)C (\%\)，分别。Kafin wannan, an tsince samfuran na mintuna biyar a cikin zazzabi na 50 \ (^\circ \) C a cikin wani maganin tabo don bakin karfe tare da maida hankali na hydrochloric da acid nitric 15-20 \ (\% \) da 1. \.(-<) 5 \ (\% \) соответственно. (-<\)5 \ (\%\) bi da bi.
Tsarin tsari na saitin gwaji na saitin DLIP mai katako guda biyu, gami da (1) katako na Laser, (2) a \(\lambda\)/2 farantin, (3) shugaban DLIP tare da takamaiman tsarin gani, (4) ) farantin zafi, (5) giciye-ruwa, (6) x, y matakan sakawa da (7) samfuran bakin karfe.Biyu maɗaukakin katako, waɗanda aka zagaye da ja a hagu, suna ƙirƙirar tsarin layi akan samfurin a kusurwoyin \(2\theta\) (ciki har da duka s- da p-polarization).
Rubutun bayanan da aka yi amfani da su da/ko aka yi nazari a cikin binciken na yanzu suna samuwa daga mawallafa bisa ga buƙatu mai ma'ana.
Lokacin aikawa: Janairu-07-2023