Insimbi eyinsimbi (No. 25 steel) yezikhonkwane zokudonsa yayisetshenziswa njenge-substrate, futhi i-austenitic stainless steel coating yayimbozwe ubuchwepheshe be-laser cladding. Ukuhleleka nokwakheka kwesendlalelo sokugquma kwahlaziywa futhi kwabonakala ngesibonakhulu se-electron yokuskena, ukuskena nokudluliswa kwe-electron, kanye ne-X-ray diffractometer. Ukuqina nokusebenza kokugqoka kuhlolwe umhloli we-microhardness kanye nomhloli wokugqoka. Imiphumela ibonisa ukuthi ungqimba lwe-austenitic stainless steel cladding ungqimba lwakhiwe ngamakristalu e-equiaxed, ama-dendrites namakristalu aplanethi, futhi indawo ethintekile ekushiseni yakhiwa i-martensite ne-troostite. Ama-dendrite wesendlalelo sokuvala ayizigaba, futhi izifunda ezihlanganisa i-interdendritic zakhiwe izigaba kanye nama-carbides Cr, C². Ubulukhuni obuncane buyancipha busuka kungqimba-ukushisa kwendawo ethintekile ukuya ku-310HVo.1-280HVo.1-170HVo.1 ngokulandelana. I-substrate yensimbi engu-25 ingukugqoka okunamathelayo nokugqokwa kwe-abrasive, futhi isendlalelo sokuvala siwukugqoka oku-abrasive; ngemuva kwe-1h yokugqoka, ukumelana nokugqoka kwesendlalelo sokubopha kuphindwe kabili kune-substrate yensimbi engu-25.

Njengengxenye ebalulekile yedivayisi yokudonsa yezitimela zikagesi, iphinikhodi yokudonsa ithwala ukungqubuzana nomthelela womzimba wenduku yokudonsa ngesikhathi sokusebenza kwesitimela. Iphinikhodi yokudonsa yesitimela sikagesi i-Harmony Electric 3C (HXD3C) ekhiqizwa inkampani ethile yenziwe nge-ZG230-450 (No. 25 steel). Phakathi nenqubo yokuphonsa, ukukhubazeka okungavamile okufana nezimbobo zesihlabathi nezimbotshana kuvame ukukhiqizwa eduze kwendawo, okungabangela kalula ukuthi iphinikhodi yokudonsa ingaphumeleli ngaphambi kokufinyelela impilo yayo yesevisi. Ngakho-ke, kuyadingeka ukulungisa amaphutha eduze kwendawo yendawo.

I-Laser cladding layer inokumelana okuhle kakhulu kokugqokwa, ukumelana nokugqwala, ukumelana nokushisa okuphezulu kwe-oxidation, ukumelana nokukhathala nezinye izinzuzo, okuye kwaholela ekuthuthukisweni okusheshayo kobuchwepheshe be-laser cladding. Uma kuqhathaniswa nezindlela zokugqoka zendabuko (ezifana nokushisela i-arc kanye nokufafaza okushisayo), i-laser cladding ingakhiqiza ukunamathela okungcono, okufana ne-microstructure eqinile, ukumelana nokugqokwa okuphezulu, izinga eliphansi lokuhlanjululwa kanye nokubopha kwe-metallurgical ne-substrate. Lobu buchwepheshe buye baba indlela ebalulekile yokulungisa ubuso nokuguqulwa kwezingxenye.

Kuleli phepha, insimbi engu-25 isetshenziswe njenge-substrate, futhi ukunamathela kwensimbi engagqwali ye-austenitic kwalungiswa ngobuchwepheshe be-laser cladding. Isakhiwo sokumboza, ubulukhuni be-microhardness nokusebenza kokugqoka kwahlaziywa futhi kwahlolwa.

1 Indlela yokuhlola
I-substrate yokuhlola yayiyinsimbi engu-25, futhi ingaphezulu laligaywe ngaphambili nge-sandpaper ukuze kukhishwe ukugqwala. Impushana yensimbi engagqwali ye-Austenitic yasetshenziswa njengendwangu ye-laser, futhi ububanzi bezinhlayiyana zayo babungu-50~100μm. I-micromorphology ye-austenitic stainless steel powder ikhonjiswe kuMfanekiso 1. Ukwakheka kwamakhemikhali ayo (ingxenye enkulu) imi kanje: C yi-0.02%, i-Si ingu-0.82%, i-Mn ingu-1.68%, i-Mo ingu-0.08%, i-Cr ingu-19.34%, i-Ni ingu-9.97%, kanti i-Fe yona ingu-68.09%.

Ngaphambi kokuhlolwa kwe-laser cladding, impushana yensimbi engenasici ye-austenitic yomiswa ngokuphelele kuhhavini owomisa ngo-120 ℃ ihora elingu-1. Ukuze kulingise izici zokukhubazeka zemigodi yesihlabathi eduze nendawo yephinikhodi yokudonsa kuze kufike ezingeni eliphezulu, ingaphezulu lensimbi engu-25 lambiwa ngomshini ngaphambi kokufakwa kwe-laser, nobubanzi bembobo obungu-4 mm kanye nokushona komgodi okungu-0.5 mm.

Kuleli phepha, YLS-6000 I-fiber laser yasetshenziswa futhi indlela yokondla impuphu ye-coaxial yasetshenziselwa ukuvala i-laser. Imingcele yenqubo ethuthukisiwe yayiyi: i-defocus eyinegethivu engu-30mm, ububanzi bendawo obungu-3mm, amandla e-laser angu-2600W, izinga lokuskena elingu-6mm/s, nezinga lokuphakela ngempushana elingu-18.9g/min ekuhlolweni kwe-laser cladding ye-single-pass; amandla e-laser angu-2500W, izinga lokuskena elingu-6mm/s, izinga lokugqagqana elingu-40%, kanye nezinga lokuphakela ngempushana elingu-18.9g/min ekuhlolweni kwe-multi-pass single-layer cladding.

Kusetshenziswa i-Leica DMi8 Isibonakhulu esibonakalayo, i-PANalytical Empyrean X-ray diffractometer, i-Zeiss Supra Inhlangano kanye nesakhiwo sokumboza kwahlaziywa futhi kwabonakala nge-55-type emission field scanning electron microscope kanye ne-JEM2100F yokudlulisela i-electron microscope. Ukuqina kwe-substrate nesendlalelo sokuvala kuhlolwe imodeli yomhloli we-microhardness HV-1000B, enesikhathi sokulayisha esingu-15s kanye nomthwalo wokuhlola we-100g. Ukuhlolwa kwenziwa kusukela endaweni enamathelayo kuya ku-substrate yensimbi engu-No.

Ukuhlolwa kokugqokwa kwasebenzisa i-UMTTriboLab friction and wear tester, ibhola lokugaya laliyi-CCr15 impahla enobubanzi obungu-5mm, ubulukhuni bebhola lokugaya bekungu-62HRC, umthwalo wokugqokwa wawungu-100N, ibanga elilinganayo lebhola lokugaya lalingu-6mm, futhi ijubane elilinganayo lalingu-4. mm/s. Isisindo se-substrate nokumbozwa ngaphambi nangemuva kokugqoka kukalwe ngebhalansi kagesi.

2 Imiphumela yokuhlolwa nengxoxo

2.1 Ukuhlaziywa kwesakhiwo esincane
Umfanekiso 2 isithombe se-electron microscope esithwebulayo sesakhiwo se-cladding layer (CL). Ngesikhathi senqubo yokuhlanganisa i-laser, i-laser beam ingumthombo wokushisa we-Gaussian onokusatshalaliswa kwamandla okungalingani. Ngesikhathi senqubo yokushisisa nokupholisa, amazinga okushisa ahlukene kanye nokupholisa azoholela ezinhlobonhlobo ze-morphology zenhlangano endaweni ngayinye. Ngokuvumelana nethiyori yokuqina, isici sokuzinza kwesixhumi esibonakalayo esiqinile-uketshezi (G/R) sinquma imo yokukhula yesakhiwo sesendlalelo esibambekayo, lapho u-G eyi-gradient yezinga lokushisa kanye no-R izinga lokuqiniswa. Kusukela ku-microstructure engaphezulu nangaphansi kwesendlalelo sokuvala, kungabonakala ukuthi ingxenye engaphezulu ye-cladding layer yakhiwa ikakhulukazi amakristalu alinganayo nama-dendrites, futhi phansi kwesendlalelo sokuhlanganisa ikakhulukazi sakhiwe ikristalu eyodwa yamakholomu. , futhi isiqondiso sayo sokukhula sincike kakhulu kumugqa wokuhlanganisa. Lokhu kungenxa yokuthi ukukhishwa kokushisa endaweni eqondile yomugqa wokuhlanganisa kuyashesha ngesikhathi senqubo yokuhlanganisa, futhi ukuhlelwa kwendawo yomugqa wokuhlanganisa yakhiwe ngamakristalu aplani.

Umfanekiso 3 ubonisa i-microstructure yendawo ethintekile ekushiseni yesampula yokuvala i-single-pass cladding. Njengoba amazinga okushisa aphakeme kakhulu atholwa yisikhundla ngasinye phakathi nenqubo yokuhlanganisa ahlukile, isakhiwo senhlangano sihlukile futhi, futhi singahlukaniswa sibe indawo yokucisha kanye nendawo evamile. Indawo yokucisha yakhiwa i-lamellar martensite. Ngesikhathi senqubo yokumboza, i-substrate eseduze nechibi elincibilikisiwe ishiselwa ngokushesha ngaphezu kwe-Acl ukuze i-austenitization, bese ipholiswa ngokushesha ukuze yakhe i-lamellar martensite. Ukuhlelwa kwendawo yokujwayela ngokuyisisekelo kuyafana naleyo ye-substrate, ngaphandle kokuthi inhlangano yendawo yokujwayela i-troostite ecolekile ngokuhlobene nenhlangano ye-matrix.

2.2 Ukuhlaziywa kwe-X-ray diffraction
I-spectrum ye-XRD ye-diffraction ye-cladding layer iboniswa ku-Figure 4. Kungabonakala ku-Figure 4 ukuthi i-austenitic stainless steel cladding layer yakhiwe isigaba esisodwa se-austenite (γ), futhi azikho ezinye iziqongo ze-diffraction ezivelayo.

2.3 Ukuhlaziywa kwe-TEM kwesendlalelo sokuvala
Umfanekiso 5 ubonisa i-microstructure kanye nezindawo ezikhethiwe zokuhlukanisa ze-austenitic stainless steel cladding layer. Umfanekiso 5 (a) isithombe se-electron microscope esithwebulayo se-microstructure yesendlalelo sokuvala; Izibalo 5 (b) kanye no-5 (c) ziyizithombe zenkambu ekhanyayo ye-electron microscope yezifunda b no-c, ngokulandelanayo; Amanani 5 (d) kanye no-5 (e) abonisa izindawo ezikhethiwe ze-electron diffraction zezifunda d (ngaphakathi kwe-dendrite) kanye no-e (phakathi kwama-dendrites). Isakhiwo esingaphakathi kwe-dendrite kuMfanekiso 5 (a) sibonakala njenge-matrix emhlophe ngaphansi kwesibonakhulu se-electron yokudlulisela, futhi indawo ehambisanayo yokuhlukanisa kuMfanekiso 5 (d) iyisigaba esine-crystal band axis yesakhiwo se-FCC, esihambisana umphumela we-XRD diffraction ku-Figure 4. Izindawo ezihlanganisiwe ku-Figure 5 (e) zalinganiswa ukuze kunqunywe ukuthi ukwakheka kwayo okufana ne-strip kuyi-Cr, Cz ye-orthorhombic system (crystal band axis is), kanye ne-matrix emhlophe ezungezile isigaba sika-γ sesistimu ye-cubic egxile ebusweni (i-crystal band axis is). Lokhu kukhombisa ukuthi uma i-laser cladding austenitic stainless steel powder, isigaba sika-γ siqala ukushona kusukela esigabeni soketshezi, bese kuba ukusabela kwe-eutectic, okwenza isakhiwo se-eutectic esinezigaba ezingu-γ nezendlalelo ze-chromium carbide lamellar. Njengoba ukuhlaziya okungenhla kwe-X-ray kungokwengqimba engaphezulu yongqimba oluhlanganisiwe, kungenzeka kakhulu ukuthi okuqukethwe kwe-carbide endaweni kungaphansi kuka-5%, ngakho akukho Cr3C2 eboniswayo.

2.4 Ukusabalalisa kokuqina okuncane
Umfanekiso wesi-6 ijika eliqinile elisuka kungqimba lokunamathisela liye ku-substrate yensimbi engu-No. 25. Kungabonakala Emfanekisweni wesi-6 ukuthi ukuqina kongqimba oluzincibilikisayo oluzincibilikisayo, indawo ethinteke ukushisa, kanye ne-substrate ibonisa inkambiso encipha kancane kancane. Kungabonakala futhi emfanekisweni ukuthi izinga lokushisa longqimba olungaphezulu likunani elibalulekile lephuzu lokuncibilika kwempushana, okuholela ekutheni impushana inamathele ebusweni bechibi elincibilikisiwe futhi ingancibiliki ngokuphelele, futhi ubulukhuni obuncane buguquguquka kancane. ; ngokukhula kwebanga, ikhwalithi yesendlalelo se-cladding ijwayele ukuzinza, inani eliphakeme le-microhardness lingu-314HV0.1, futhi ubulukhuni obuncane buzinzile cishe ku-310 HV0.1.

Ngesikhathi senqubo yokuvala i-laser, izinga lokushisa eliphezulu elitholwa indawo ngayinye ethinteke ukushisa lihlukile, futhi izinga le-austenitization nalo lihlukile. Indawo yokucisha yendawo ethinteke ekushiseni eduze komugqa wokuhlanganisa inezinga lokushisa eliphakeme kune-liquidius phakathi nenqubo yokuhlanganisa. Ngemuva kokupholisa ngokushesha, kutholakala isakhiwo se-martensitic esinamandla aphezulu, ukuze ubuncane bayo bugcinwe cishe ku-280HV0.1. Ngokukhula kwebanga elingaphezulu, ingxenye yesakhiwo se-martensitic iyancipha kancane kancane. Uma ifinyelela endaweni evamile yendawo ethintekile ekushiseni, ukwakheka kwayo ikakhulukazi i-ferrite ne-troostite enhle. Njengoba ukujula kukhula, izinga lokupholisa ngemva kokugqoka liyancipha kancane kancane, futhi ubuncane bayo kancane kancane buyehla kancane kancane buqine be-substrate yensimbi engu-25, okungukuthi, 170 HV0.1.

2.5 Ukuhlaziywa kokuhlola kokungqubuzana nokugqoka
Umfanekiso wesi-7 ubonisa ijika eliguqukayo lokuguga okukhulu kwe-substrate kanye nongqimba lwe-laser yensimbi engenasici ye-austenitic ngaphansi kwezimo zokungqubuzana ezomile ngokuhamba kwesikhathi. Ngaphansi kwesikhathi esifanayo sokugqoka, ukulahlekelwa kwesisindo sokugqoka kwesendlalelo se-cladding kuhlale kungaphansi kwe-substrate, futhi njengoba isikhathi sokugqoka sikhula, igebe phakathi kokubili liya likhula futhi libe likhulu. Ngemuva kwemizuzu engu-30 yokugqoka, ukulahlekelwa kwesisindo sokugqoka kwe-substrate cishe izikhathi ezingu-1.5 kunesendlalelo sokuvala; ngemuva kwehora elingu-1 lokugqoka, ukwehla kwesisindo sokugqoka kwe-substrate cishe izikhathi ezi-2 kunesendlalelo sokuvala. Lokhu kukhombisa ukuthi ngemuva kwe-laser cladding ye-austenitic stainless steel coating, ukumelana nokugqokwa kuthuthukiswa kakhulu.

Ngokomshini wokuguga, ukugqokwa kungahlukaniswa kube ukukhathala, ukuguguleka komhlabathi, ukunamathela okunamathelayo, ukuguguleka, njll. Ngokuvamile, ukuziphatha kokuguga kuvame ukubuswa indlela ethile, futhi izindlela eziningi zenziwa ngesikhathi esisodwa. Umfanekiso 8 ubonisa ukuguga kwe-substrate kanye nongqimba lwensimbi engenasici ye-austenitic ngemva kokugqokwa kwehora elingu-1. Njengoba kungabonwa kuMfanekiso 8, imisele ye-substrate material ngemva kokugqoka ijulile futhi inezinga elithile lokuguquguquka kwepulasitiki. Isenzakalo sokunamathela emaphethelweni sibonakala kakhudlwana, okuyisici esivamile sokugqoka okunamathelayo nokugqoka okuhuquzelayo. Lokhu kungenxa yokuthi ubulukhuni be-substrate buphansi futhi imigodi yokuxebula ivela ngesikhathi senqubo yokugqoka. Izimpawu zokugqokwa ze-austenitic stainless steel cladding layer azishoni, zinenani elincane lamamaki axebukayo, ikakhulukazi ngenxa yokuguga. Lokhu kungenxa yokuthi ukupholisa okusheshayo kwe-laser cladding kwenza ungqimba lwe-austenitic stainless steel cladding lube luhle, oludlala indima ekusekeleni nasekuxhumeni isigaba sokuqinisa esingagugi phakathi nenqubo yokuguga. Isigaba esinzima kanye nesigaba esiqinile u-Cr, Cz kungqimba yokunamathisela kusebenza ndawonye ukuze kuthuthukiswe ukumelana kwayo nokugqokwa.

3 Iziphetho

(1) I-austenitic stainless steel cladding layer yakhiwe ngamakristalu alinganayo, ama-dendrites namakristalu aplanethi, futhi indawo ethinteke ukushisa yakhiwe i-martensite ne-troostite. Ama-dendrites we-cladding layer akhiwa izigaba, futhi izigaba ze-interdendritic zakhiwa izigaba kanye ne-carbides Cr; C2.

(2) Ukuqina okuncane kokuzincibilikisa okuzincibilikisayo-ukushisa okuthintekile kwendawo-substrate kancane kancane kuncipha kuya ku-310 HVo.1-280 HVo.1-170 HVo.10
(3) I-substrate yensimbi engu-No. 25 ingaphansi kokunamatheliswa nokuguga, futhi ungqimba lokunamathisela lungaphansi kokuguga. Ngemuva kwehora elingu-1 lokugqoka, ukulahlekelwa kwesisindo sokugqoka kwe-substrate cishe kabili kunesendlalelo sokuvala, okungukuthi, ukumelana nokugqoka kwe-austenitic stainless steel cladding layer kuphindwe kabili kune-No. 25 steel substrate.