Hnav thiab corrosion yog ob qho tseem ceeb ua rau qhov tsis ua hauj lwm ntawm cov khoom. Txawm li cas los xij, cov txheej txheem ntxiv dag zog xws li tshuaj kho cua sov, laser cladding, vapor deposition, electroplating thiab txau tuaj yeem txhim kho qhov hnav tsis kam ntawm cov hlau. Tam sim no, nitriding kev kho tshuab thiab laser cladding tshuab yog ib qho kev siv dag zog, thiab tau siv dav hauv kev lag luam offshore, aviation, nuclear zog thiab lwm yam kev lag luam. Lub FeCrNiMo txheej tau npaj los ntawm laser cladding technology. Nws tau pom tias nyob rau hauv daim ntawv ntawm lub nplhaib-thaiv kev sib txhuam hnav, lub ntsiab mechanism ntawm txheej cladding yog abrasive hnav thiab oxidation hnav. Nyob rau hauv daim ntawv ntawm pob thiab disc reciprocating kev sib txhuam thiab hnav, txheej cladding yog dominated los ntawm oxidation hnav thiab qaug zog hnav mechanism.
Cov txheej txheem nitriding ib txwm muaj teeb meem ntawm lub sijhawm ntev thiab kev ua haujlwm qis. Txhawm rau txhim kho nitriding efficiency thiab txo cov nkig nitriding txheej, thiab txuas ntxiv txhim kho cov txheej txheem siab nitriding, cov teeb meem tseem ceeb tau ntsib tam sim no.
Lub zog khi ntawm Ti thiab N muaj zog heev. Ntxiv qhov tsim nyog Ti tuaj yeem ua rau cov tawv tawv thiab qhov tob ntawm nitriding txheej, thiab txhim kho cov txiaj ntsig nitriding. Nyob rau tib lub sijhawm, Ti muaj cov nyhuv ntawm refining nplej, uas tuaj yeem txhim kho lub toughness ntawm siab nitriding txheej. Yog li ntawd, nyob rau hauv daim ntawv no, sib txawv Ti ntsiab lus (NiCr) 92-x Mo8Tix (x=2), Cov teebmeem ntawm Ti cov ntsiab lus ntawm microstructure, hardness, hnav tsis kam thiab corrosion kuj ntawm Ni-Cr-Mo- Ti laser cladding thiab plasma nitriding composite txheej tau kawm, kev hnav thiab corrosion mechanisms tau tham los muab theoretical thiab sim hauv paus rau kev txhim kho cov hnav thiab corrosion kuj ntawm txheej.
1. Cov ntaub ntawv sim thiab cov txheej txheem
304SS tau xaiv los ua cov khoom siv hauv paus, Ni, Cr, Mo, Ti hlau hmoov nrog purity siab dua 99.95 pawg% thiab qhov loj me ntawm 48 ~ 74 μm raug xaiv. Qhov hnyav tau ua raws li molar ratio (NiCr) 92-x Mo8Tix (x=2 thiab 4 ntawm%). Txhawm rau kom yooj yim cov lus piav qhia, cov txheej txheej npaj tau muab npe S1 thiab S2 raws li, thiab lub cev muaj pes tsawg leeg tau pom nyob rau hauv Table 1. Cov hmoov muab tso rau hauv lub tshuab nqus tsev stainless hlau, lub pob stainless hlau yog siv los ua cov pob zeb sib tsoo rau 6. h, thiab cov hmoov av qhuav hauv lub tshuab nqus tsev ziab ntawm 60 degree rau 24 teev. Cov hmoov hlau alloy nrog lub thickness ntawm 2 hli tau coated rau saum npoo ntawm matrix los ntawm preset hmoov txoj kev, thiab optical fiber semiconductor excizer (LSJG-BGQ-2000) nrog lub siab tshaj plaws tso zis zog ntawm 2 kW yog siv rau cladding. Lub hwj chim yog 2.0 kW, tus nqi scanning yog 30 mm / min, qhov sib tshooj ntawm ntau channel cladding yog 40% ~ 50%, thiab Ar gas kis mus rau AR roj ntawm tus nqi ntawm 15 L / min. Cov qauv no tau nitrided los ntawm ntsug auxiliary cua sov ion nitriding rauv (FD-WR60/80) nrog kev khiav hauj lwm voltage ntawm 720 V, nqus tsev kawm ntawv ntawm (350 ± 10) Pa, nitriding kub ntawm 540 degree, thiab tuav lub sij hawm ntawm 8 h. Cov npe piv txwv yog 304-N, S1-N thiab S2-N tom qab nitriding, thaum N2 thiab H2 raug txhaj rau hauv qhov sib piv ntawm 1: 5.
Table 1 Chemical compositions of the (NiCr) 92-x Mo8 Tix coatings (at%)
|
Qauv |
Ni |
Cr |
Mo |
Ti |
|
S1 |
45 |
45 |
8 |
2 |
|
S2 |
44 |
44 |
8 |
4 |
Cov qauv raug txiav rau hauv 10 mm × 5 mm kuaj blocks los ntawm cov hlau txiav tshuab, polished thiab polished rau cov txheej txheem kub, thiab corroded nrog huab tais dej (HCl ∶ HNO3=3 ∶ 1). Cov theem muaj pes tsawg leeg ntawm cov qauv tau soj ntsuam los ntawm D/MAX-2500PC X-ray diffractometer (XRD). Lub hom phiaj Cu K (λ=0.15405 nm) yog siv los ua cov hluav taws xob hluav taws xob, lub raj hluav taws xob yog 40 kV, lub raj tam sim no yog 100 mA, thiab lub kaum sab xis scanning yog 20 degree ~ 100 degree. Scanning electron microscopy (SEM, FEI Nova NanoSEM 450) thiab lub zog dispersive spectroscopy (EDS) tau siv los tshuaj xyuas cov microstructure, tshuaj muaj pes tsawg leeg thiab nitriding thickness ntawm txheej. Vickers hardness tester (HVS{13}}) tau siv los ntsuas qhov microhardness ntawm cov txheej txheej thiab los ntawm sab saum toj ntawm txheej mus rau substrate nrog load ntawm 100 g thiab lub sij hawm thauj khoom ntawm 15 s. Lub pob reciprocating thiab phaj kev sib txhuam thiab hnav lub tshuab kuaj (Rect MFT-5000) tau siv los kuaj cov kab ntawm cov txheej txheem raws li hauv qab no: lub sijhawm thauj khoom yog 20 N, lub sijhawm hnav yog 10 min, thiab cov khoom sib tsoo yog Al2 O3 pob nrog txoj kab uas hla ntawm 9.8 hli. Kev sib txhuam coefficient (COF) tau sau tseg rau tib lub sijhawm, thiab kev puas tsuaj morphology tau txheeb xyuas los ntawm BRUKER Contour GT-K1 thiab SEM. Tus cwj pwm corrosion ntawm cladding txheej thiab nitriding nto tau sim siv cov tsoos peb-electrode system hom. Cov cuab yeej xeem yog Gmary Reference 3000 electrochemical workstation. Qhov chaw kuaj tau siv los ua cov khoom siv hluav taws xob ua haujlwm, saturated calomel electrode (SCE) tau siv los ua cov khoom siv hluav taws xob, thiab cov platinum electrode tau siv los ua lub txee electrode. Cov electrolyte yog 3.5 pawg% NaCl tov. Cov qauv yog tsau rau hauv 1 mol / L HCl tov rau 24 h, ntxuav me ntsis nrog dej cawv thiab qhuav, thiab cov tshuaj tiv thaiv corrosion tau soj ntsuam los ntawm SEM.
2. Cov lus xaus
1) (NiCr) 92-x Mo8 Tix cladding txheej yog tsim los ntawm FCC theem, σ-CrMo theem thiab me me ntawm Cr2Ti theem. Kev tsim ntawm (Cr, Ti) N theem tom qab kev kho nitriding. Nrog rau qhov nce ntawm Ti cov ntsiab lus, cov ntsiab lus ntawm (Cr, Ti) N theem nce, thiab lub thickness ntawm nitriding txheej nce.
2) Nrog rau qhov nce ntawm Ti cov ntsiab lus, txheej txheej hardness nce mus txog 531 HV0.1. Tom qab kev kho nitriding, lub hardness ntawm txheej yog heev nce, thiab qhov siab tshaj plaws yog 1258 HV0.1. Kev sib txhuam coefficient, qhov dav thiab qhov tob ntawm cov cim hnav thiab hnav ntim ntawm 304SS yog ntau me dua li cov txheej tsis-nitriding thiab kev kho nitriding. Cov hnav mechanism hloov los ntawm cov nplaum hnav mus rau abrasive hnav, thiab hnav tsis kam yog qhov zoo dua.
3) Lub corrosion tam sim no ntom ntom (Icorr) ntawm nitriding txheej yog qis dua li ntawm cov txheej tsis-nitriding thiab 304SS tom qab nitriding, thiab tsis muaj qhov tshwm sim pitting tshwm sim. Ntawm lawv, S1-N muaj kev tiv thaiv corrosion zoo dua hauv 3.5 pawg% NaCl tov. Cov txiaj ntsig ntawm immersion corrosion test qhia tau hais tias tsuas muaj cov cim corrosion me ntsis ntawm cov txheej txheej tom qab nitriding, thiab kev txhim kho corrosion kuj zoo dua.
Xi'an Guosheng Laser Technology Co., Ltd. yog lub tuam txhab high-tech tshwj xeeb hauv R & D, tsim thiab muag cov tshuab laser tsis siv neeg cladding, high-speed laser cladding tshuab, laser quenching tshuab, laser vuam tshuab thiab laser 3D tshuab luam ntawv. Peb cov khoom raug nqi zoo thiab muag hauv tsev thiab txawv teb chaws. Yog tias koj txaus siab rau peb cov khoom, thov hu rau peb ntawm bob@gshenglaser.com.