Pofuna kupititsa patsogolo kukana kwazitsulo zamakina okhudzana ndi nthaka, FeCoCrNiMn high entropy alloy, Fe90 alloy ndi Ni60A. alloy powders adasankhidwa kuti aphunzire mofananiza. Chophimba chosamva kuvala chinakonzedwa ndi laser cladding luso yokhala ndi chitsulo cha 65Mn monga gawo lapansi, ndipo magwiridwe ake amavalidwe adayesedwa ndi makina oyesa akulimbana ndi kuvala. Zotsatirazo zinasonyeza kuti FeCoCrNiMn high entropy alloy coating inali ndi mawonekedwe olimba kwambiri, njere zophweka, ndipo palibe zovuta zowonongeka za intermetallic zomwe zinapangidwa; kugawa kwambewu kwa microstructure kwa zokutira za Ni60A ndi Fe90 kunali kosokoneza. Zovala zotayika za 65Mn steel substrate, alloy Ni60A, Fe90 alloy ndi FeCoCrNiMn high entropy alloy coating zinali 9, 4, 5 ndi 2 mg motsatana, ndipo kutayika kwa gawo lapansi kunali kwakukulu kwambiri kuposa zokutira. Kuuma kwa Vickers kwa Fe90 ndi Ni60A alloy zokutira ndi 683.87 ndi 663.62 HV, ndipo kuuma kwa Fe-CoCrNiMn high entropy alloy coating ndi 635.81 HV, yomwe ili yotsika pang'ono kuposa zokutira zina, koma kukana kwake kuvala kuli bwino.

Ndi kukula kwachangu kwa makina ndi zida zaulimi, mbali zolumikizana ndi nthaka zamakina aulimi zimakhudzidwa ndi kutayika kwamphamvu komanso kugwedezeka kwa ma abrasives monga dothi ndi mchenga kwa nthawi yayitali, zomwe zimayika zofunika kwambiri pakukana kwa nthaka yachikhalidwe. -kukhudzana mbali. Pakati pa njira zosiyanasiyana zotsutsana ndi kuvala, kuphimba ndi laser ndi chithandizo chapamwamba cha malo olephera kukhudza nthaka ndi njira ziwiri zomwe zimagwiritsidwa ntchito kawirikawiri. Onse amagwiritsa ntchito zodzaza zosiyanasiyana kuti asungunuke kapena kutenthetsa zokutira kuti zikhale zosungunuka ndikuziphimba pamwamba pa gawo lapansi, potero zimakweza kukana kwa gawo lapansi. Zida ziwiri zomwe zimagwiritsidwa ntchito kwambiri popaka dothi ndizitsulo zopangidwa ndi chitsulo ndi nickel-based alloys. Zida zokutira zonse ziwiri zimatengera chinthu cha alloy ndikuwongolera magwiridwe antchito powonjezera zinthu zina zoyenera. Pakalipano, kafukufuku ndi kugwiritsa ntchito kuwongolera kukana kuvala kwa zida zachitsulo zachikhalidwe zatsala pang'ono kukhutitsidwa, ndipo danga la kafukufuku likucheperachepera.

Ma aloyi apamwamba a entropy amapangidwa ndi zinthu zosiyanasiyana zophatikizika ndi ma atomiki ofanana, okhala ndi magawo ofananirako komanso osavuta okhazikika, owonetsa mphamvu zambiri, kukana kuvala kwambiri komanso kukana kwa dzimbiri. Pogwiritsa ntchito ufa wochuluka wa entropy alloy pokonzekera zokutira zosagwira ntchito pamakina aulimi omwe amalumikizana ndi dothi, mbalizo zimakhala ndi kukana kwambiri ndipo zimatha kuwonjezera moyo wawo wautumiki.

Ukadaulo wa laser cladding umagwiritsidwa ntchito pokonzekera zokutira, zomwe zimakhala ndi zabwino za kutentha kwapakati komanso madera ang'onoang'ono omwe amakhudzidwa ndi kutentha. Mapangidwe a bungwe omwe amapangidwa m'malo oponyera nawonso ndi osiyana ndi njira zina zotchingira, monga electrospark deposition, magnetron sputtering ndi plasma cladding. Nthawi yomweyo, ukadaulo wa laser cladding umagwiritsidwa ntchito pokonzekera zokutira, ndipo gulu la amorphous limapangidwa mu bungwe lopaka. Pakalipano, pali maphunziro ochepa okhudza kugwiritsa ntchito zipangizo zokutira za entropy alloy pokonzekera zokutira zosamva kuvala kwa zida zaulimi zomwe zimagwira nthaka. Papepalali, alloy Fe90, Ni60A alloy ndi FeCoCrNiMn high entropy alloy wear-resistant zokutira zidakonzedwa pamwamba pa chitsulo cha 65Mn pogwiritsa ntchito ukadaulo wa laser cladding. Kukangana ndi kuvala kwa zokutira zapamwamba za entropy alloy zinafaniziridwa ndikuphunziridwa, ndipo malamulo awo a tribological adafufuzidwa kuti apereke chidziwitso pakukulitsa kwa ntchito kwa ma aloyi apamwamba a entropy.

1 Zida zoyesera ndi njira

1. 1 Kukonzekera zokutira
Chitsanzocho chinagwiritsidwa ntchito 65Mn high carbon spring steel steel monga maziko, ndipo chinadulidwa mu zitsanzo ndi kukula kwa 200 mm × 400 mm × 4 mm pogwiritsa ntchito makina odulira metallographic. Chitsanzocho chinali pansi ndikupukutidwa chisanatsekeredwe kuti chitetezeni kuti kusanjikiza kwa oxide, mafuta ndi zonyansa zina pamtunda wa chitsanzo zisakhudze mphamvu yomangira pakati pa zokutira ndi chitsanzo. 80, 120, 220, 800, 1 000, 1 500 ndi 2 000 grit sandpaper anagwiritsidwa ntchito popera motsatizana. The opukutidwa chitsanzo anali ultrasonically kutsukidwa Mowa kwa 5 min, anaika mu kuyanika uvuni pa 105 ℃ kwa 10 min, ndi losindikizidwa ndi kusungidwa pambuyo kuyanika. Fe90 alloy, Ni60A alloy ndi FeCoCrNiMn high entropy alloy powder (tinthu kukula kwa 45 mpaka 105 μm) anasankhidwa ngati cladding wosanjikiza zipangizo. Kuphatikizika kwa mankhwala a zida zoyesera ndi ufa zikuwonetsedwa mu Table 1. Mphamvu yayikulu yotulutsa ya CW-CBW-8000G-91-20L zida za laser cladding ndi 25,000 W. Mayesowa amatengera njira yopangira ufa wa axis Broadband powder, argon. gasi woteteza, ndipo makulidwe a zokutira ndi 1 mm. Ma parameters a cladding process akuwonetsedwa mu Table 2.

1.2 Mawonekedwe a mayeso
Chitsulo cha 65Mn ndi chitsanzo cha S1, zokutira za alloy za Ni60A ndi chitsanzo cha S2, zokutira za alloy Fe90 ndi chitsanzo cha S3, ndi FeCoCrNiMn high entropy alloy coating ndi chitsanzo cha S4. The metallographic etching solution ya chitsanzo S1 ndi 4% nitric acid solution (moyikira nitric acid ndi anhydrous ethanol, chiŵerengero cha voliyumu ndi 4: 100); Metallographic etching solution ya chitsanzo S2 ndi mkuwa sulfate pentahydrate njira (hydrochloric acid, madzi ndi mkuwa sulphate, voliyumu chiŵerengero ndi 10: 10: 1); The metallographic etching solution of samples S3 ndi S4 ndi 5% aqua regia (concentrated hydrochloric acid and concentrated nitric acid, volume ratio ndi 3: 1).

Metallographic microstructure ya chitsanzo inawonedwa ndi Leica DM4000M metallographic microscope; kuuma kwa pamwamba ndi gawo lonse la chitsanzo kunayesedwa ndi Jinan Times TMVS-1 chiwonetsero cha digito Vickers kuuma woyesa; kukangana ndi kuvala kwa zinthuzo kunadziwika ndi MMU-10 yoyendetsedwa ndi microcomputer kumapeto kwa nkhope ndikuyesa kuvala; pin-disc friction pair idagwiritsidwa ntchito poyesa, ndipo mpira wopera unali mpira wopera wa ZrO2 wokhala ndi mainchesi 6 mm. Zoyesererazo zinali zonyamula 50 N, liwiro la 80 r / min, ndi nthawi yolimbana ndi 120 min; morphology ya zipsera zovala pambuyo poyesa kugundana ndi kuvala kwachitsanzocho zidawonedwa ndi maikulosikopu.

Zotsatira zoyesa ndikuwunika

2.1 Metallographic kapangidwe ka zokutira
Chithunzi 1 chikuwonetsa mawonekedwe a metallographic mawonekedwe a zitsanzo S1, S2, S3 ndi S4. Monga momwe tawonetsera pa Chithunzi 1a, mawonekedwe a chitsanzo S1 amapangidwa makamaka ndi ferrite ndi pearlite zomwe zimagawidwa mu grid mawonekedwe. Zitha kuwoneka bwino kuchokera ku Chithunzi 1b kuti microstructure ya zokutira za chitsanzo S2 ndi dendrites ndi reticular eutectics, gawo la bungwe ndi labwino kwambiri, ndipo ma dendrites ndi osokonekera, ndipo mabungwe aatali ndi otsekeka amapangidwa mosakhazikika. Monga momwe tawonetsera pa Chithunzi 1c, mawonekedwe ang'onoang'ono a gawo la mtanda wa zokutira za chitsanzo S3 ndi dendrites coarse ndi yunifolomu, interlaced dendrite mabungwe, ndi chiwerengero chachikulu cha kuwala chonyezimira granular precipitations. Monga momwe tawonetsera pa Chithunzi 1d, gulu lapakati la zokutira lachitsanzo la S4 ndilolitali kwambiri, makamaka lopangidwa ndi makhiristo a equiaxed mofanana, ndipo mabowo osakhazikika amapangidwa. Poyerekeza mabungwe anayiwa, kukula kwa njere za S4 ndizing'ono kwambiri, njerezo zimakhala zowuma komanso zofanana, njere zimakhala zosavuta, ndipo palibe mapangidwe ovuta a intermetallic compound.

2. 2 Microhardness ya zokutira
Chithunzi 2 ndi kuyerekezera kwa microhardness pamwamba pa zitsanzo. Kuuma kwa Vickers kwa zitsanzo S1, S2, S3 ndi S4 ndi za 234.02 HV, 683.87 HV, 663.62 HV ndi 635.51 HV motsatana. Chithunzi 3 ndikufanizira kwapang'onopang'ono kwapang'onopang'ono kwa zitsanzo. Zitha kuwonedwa kuchokera ku Chithunzi 3 kuti pafupifupi kuuma kwa Vickers kwa zokutira za zitsanzo za S2 ndi S3 ndi 3 mpaka 4 nthawi zambiri kuposa chitsanzo cha S1, kusonyeza kuti kuuma kwa zokutira za S2 ndi S3 ndizokwera kwambiri ndi zitsulo zopangira zitsulo. zotsatira ndi bwino. Kuuma kwapakati kwa Vickers kwa zokutira pamwamba pa zitsanzo za S4 ndizotsika pang'ono kuposa zitsanzo za S2 ndi S3. Izi ndichifukwa choti pamene FeCoCrNiMn high entropy alloy powder imakhazikika mofulumira, kupotoza kwa lattice kumakhala kochepa, ndipo mawonekedwe a kristalo a FCC amawotchedwa ndipo amabalalika mu amorphous ya cladding layer, yomwe imatha kuwonetseratu kuti FeCoCrNiMn high entropy alloy. zokutira ali kulimba bwino ndi otsika kuuma.

2.3 Kukantha ndi kuvala katundu
2.3.1 Avereji ya friction coefficient
Chithunzi 4 ndi pafupifupi friction coefficient pamapindikira a zitsanzo S1, S2, S3 ndi S4. Zitha kuwoneka kuti kutentha kwapakati, kugunda kwapakati pamtundu wa S1 kumakhala pafupifupi 0.53, ndipo kugunda kwapakati kumasinthasintha kwambiri mphindi 20 zoyambirira, kukwera mpaka pafupifupi 0.6; m'kupita kwa nthawi, pafupifupi friction coefficient imakhala yokhazikika. Izi zili choncho chifukwa kumayambiriro kwa kukangana pakati pa mpira wopera wa S1 ndi ZrO2, pali zinyalala zambiri pakati pa chizindikiro cha kuvala ndi mpira wogaya, zomwe zimapanga kupsinjika kwakukulu kwa kumeta ubweya, zomwe zimapangitsa kusinthasintha kwakukulu kwa coefficient ya kukangana. Pafupifupi ma coefficients okangana a zitsanzo za S2, S3 ndi S4 ndi pafupifupi 0.38, 0.32 ndi 0.25. Kugawidwa kovutirapo kwa tinthu tating'onoting'ono mu chitsanzo cha S2 kumapangitsa kuti ma curve coefficient curve azisinthasintha kwambiri. Kuuma kwa zitsanzo za S3 ndi S4 ndizochepa kwambiri kuposa za mpira wopera wa ZrO2. Chophimba cha alloy chokhala ndi kulimba kocheperako chimakhalanso ndi mphamvu yakumeta ubweya wocheperako, zomwe zimathandiza kuchepetsa kugunda kwapakati pa kukangana. Mitundu yokhotakhota yokhotakhota ya zitsanzo za S3 ndi S4 imakhala ndi mchitidwe womwewo, ndikusunga kukhazikika kokhazikika. Pakati pawo, kugunda kwapakati kwachitsanzo cha S4 ndikotsika kwambiri, mphamvu yolimbana ndi mphamvu yomweyo ndiyochepa kwambiri, ndipo digiri yovala ndiyotsika kwambiri. Izi zili choncho chifukwa chitsanzo cha S4 chikazizira mofulumira, pali magawo ochepa odetsedwa, chophimba pamwamba chimakhala chosalala ndipo chimakhala ndi zolakwika zochepa, ndipo kukhudzana ndi mpira wopera wa ZrO2 kumakhala kosavuta, popanda kusinthasintha koonekera komanso kwakukulu.

2. 3. 2 Valani kuchepetsa thupi
Deta ya kuvala yolemetsa ya zitsanzo ikuwonetsedwa mu Chithunzi 5. Kutayika kwakukulu kwa kutayika kwa chitsanzo cha S1 ndi 9 mg, ndipo kutayika kwa zitsanzo za S2 ndi S3 ndi 4 mg ndi 5 mg motsatira. Pakati pawo, kutaya kwachitsanzo S4 ndikotsika kwambiri, komwe kuli 2 mg. Izi ndichifukwa choti chophimba cha FeCoCrNiMn high entropy alloy chili ndi gawo limodzi la FCC, pulasitiki wapamwamba komanso kulimba kwabwino. Pansi pa mkangano wokhudzana ndi katundu wa 50 N, FeCoCrNiMn high entropy alloy alloy material imatha kuyamwa mphamvu zambiri, sizovuta kupanga kutopa, ndipo imakhala ndi kukana kwabwino.

2.3.3 Valani morphology kusanthula
Chithunzi 6 chikuwonetsa mawonekedwe a zipsera zovala za zitsanzo zinayi zomwe zidawonedwa pansi pamiyeso yofananayo pambuyo povala mphindi 120. Monga tikuwonera pa Chithunzi 6a, S1 ili ndi kupindika kwakukulu kwa pulasitiki chifukwa cha kuuma kwake kocheperako, malo opindika a chilondacho ndi owuma, pali gawo lalikulu la zomangira, ndipo delamination imachitika. Monga tikuonera pa Chithunzi 6b, ❖ kuyanika pamwamba pa chitsanzo S2 amagawidwa mosagwirizana ndi elliptical dot-woboola pakati pa madontho oyera, omwe amawonjezera kuuma kwa zokutira, limodzi ndi zipsera zoonekeratu kuvala ndi mizere unidirectional. Kulimba kwa pamwamba kwa chitsanzo cha S3 ndikokwera kwambiri, monga momwe tawonetsera pa Chithunzi 6c, kukula kwa zipsera ndi zopapatiza, ndipo ma groove omwe ali pamwamba pake ndi osaya. Mosiyana ndi zimenezi, mu Chithunzi 6d, grooves ya zokutira chitsanzo S4 ndi yosalala kwambiri, chifukwa cha yunifolomu dongosolo cladding wosanjikiza, mbewu zabwino, ndi bwino kuvala kukana; pali ma pores owoneka bwino m'mitsempha, omwe amatha chifukwa cha ufa wapamwamba wa entropy alloy womwe umasakanizidwa ndi mpweya wosungunuka pansi pa kutentha kwakukulu kwa mtengo wa laser, ndi mpweya wotuluka pamene chitsanzocho chakhazikika kuti chipange pores. .

Pansi pa mayesero omwewo, kukula kwake kwakukulu kwa chiwopsezo kumavala chilonda, kumachepetsanso kulemera kwakukulu. Poyerekeza kulemera kwa zitsanzo zosiyanasiyana mu Chithunzi 5, zikhoza kuwoneka kuti ubale pakati pa kukula kwa chitsanzo kuvala chipsera ndi S1> S3> S2> S4. Izi zikugwirizana ndi zotsatira zoyesa za kuchepa kwa thupi zomwe zikuwonetsedwa pa Chithunzi 5.

Kutsiliza

1) FeCoCrNiMn mkulu entropy zokutira aloyi ili ndi mawonekedwe olimba kwambiri komanso kukula kwake kochepa kwambiri, pomwe kugawa kwambewu ya microstructure ya Ni60A ndi Fe90 aloyi zokutira ndizosokoneza kwambiri. Chophimba cha FeCoCrNiMn high entropy alloy chili ndi njere yosavuta komanso palibe zovuta za intermetallic zomwe zimapangidwa.

2) Kuuma kwa Vickers kwa Ni60A alloy, Fe90 alloy ndi FeCoCrNiMn high entropy alloy coatings pafupifupi 683.87, 663.62 ndi 635.51 HV, yomwe ili yokwera kwambiri kuposa kuuma kwa Vickers kwa gawo lapansi (234.02 HV). Kuuma kwa mtengo wa Fe-CoCrNiMn high entropy alloy coating ndi yotsika pang'ono kuposa ya Ni60A alloy ndi Fe90 alloy coatings, zomwe sizimakhudza kukana kwake kuvala.

3) Zovala zotayika za 65Mn chitsulo gawo lapansi, Ni60A alloy, Fe90 alloy ndi Fe-CoCrNiMn high entropy alloy coating ndi 9, 4, 5 ndi 2 mg motsatira. Chipsera chovala cha FeCoCrNiMn high entropy alloy coating ndiye chosalala kwambiri, chokhala ndi zipsera zozama kwambiri, kutaya kwazinthu zazing'ono komanso kukana kwambiri kuvala.