02
Xaiv cov duab thiab cov ntawv nyeem
1. Kev Taw Qhia: Qhov Mob Cov Ntsiab Lus ntawm Kev Tsim Kho Kev Lag Luam thiab Kev Yug ntawm UVA-LM
Traditional laser manufacturing ntsib peb cov teeb meem tseem ceeb:
Tseem ceeb thermal defects
Qhov kub thiab txias gradients sai sai yooj yim ua rau lub hauv paus sib cais, tsim cov nkig intermetallic tebchaw, tawg, thiab residual stress;
Tsis yog-ib puag ncig microstructure
Hauv kev ua cov ntaub ntawv siab heev xws li siab -entropy alloys (HEAs) thiab refractory alloys, tsis yog -cov qauv microstructures dominated los ntawm columnar nplej yog nquag tshwm sim, cuam tshuam kev ua haujlwm ruaj khov;
Tsawg txheej txheem efficiency
Cov dej ntws tsis zoo ntawm lub pas dej ua rau lub cev tsis sib xws (piv txwv li, hmoov kwj divergence nyob rau hauv kev qhia lub zog deposition).
To address these problems, ultrasonic vibration-assisted laser manufacturing (UVA-LM) emerged – by synchronously applying high-frequency ultrasonic vibration (>20 kHz) nrog lub laser, nws siv lub "acoustic streaming + cavitation" dual mechanism los tswj lub pas dej da dej thiab ua kom muaj kev sib koom ua ke ntawm kev tsim khoom (Daim duab 1).
2. Ultrasonic vibration-Assisted Laser Additive Manufacturing (UVA-AM)
UVA-AM feem ntau yog siv rau laser hmoov txaj fusion (LPBF) thiab qhia lub zog tso nyiaj (DED), nrog rau lub hom phiaj tseem ceeb ntawm kev daws cov teeb meem ntawm "anisotropy" thiab "metallurgical defects" hauv kev tsim khoom ntxiv.
2.1 Txheej Txheem Tsim: Yuav ua li cas kom ua tiav kev sib txuas ntawm ultrasound thiab kev tsim khoom ntxiv?
UVA-LPBF System
(Daim duab 4): A 40 kHz siab- zaus vibration yog tsim los ntawm piezoelectric ceramic transducer thiab xa mus rau lub substrate ntawm lub amplitude transformer, ua tiav synchronization ntawm laser scanning thiab ultrasonic kev co (ultrasonic zog yog adjustable, raug amplitude yog 20 μm);
UVA-DED System
(Daim duab 6): Cov hmoov dav hlau trajectory yog tswj los ntawm ultrasonic kev co, tsim ib qho "ultrasound-particle coupling qauv" (kev kwv yees raug 97.7%), txo cov hmoov dispersion lub kaum sab xis ntawm 15.3℃mus rau 14.1 degree, thiab txhim kho kev faib khoom sib xws los ntawm 11.5%.
2.2 Kev Txhim Kho Kev Ua Haujlwm: Dual Optimization ntawm Microstructure thiab Mechanical Properties
Grain Refinement
Noj GH5188 siab-kub alloy ua piv txwv (Daim duab 7), UVA-LPBF tuaj yeem txo qhov nruab nrab ntawm cov nplej loj los ntawm 80.91 μm mus rau 53.02 μm, thiab {001} kev ntxhib los mos ntawm 10.37 MUD (Multiple Oriention.6 MUD, 6 units) txo qis mechanical anisotropy;
Txhim kho Mechanical Properties
Microhardness: Qhov nruab nrab hardness ntawm GH5188 alloy nce 4.49% tom qab kev pab ultrasonic (287.7 HV → 300.6 HV);
Tensile zog: Tom qab UVA-DED kev kho mob, elongation ntawm 1Cr12Ni3MoVN alloy nce 53.8%, thiab cov khoom ntawm lub zog thiab elongation (PSE) nce 52.9% (Daim duab 13);
Kev Txhaum Cai
Hauv Inconel 718 / Ti6Al4V cov khoom sib xyaw, kev pab cuam ultrasonic tuaj yeem txo cov ntsiab lus ntawm Ti₂Ni intermetallic tebchaw los ntawm 48.3%, thiab lattice mismatch los ntawm 12.7% mus rau 7.4% (Daim duab 9).
3. Ultrasonic vibration-Assisted Laser Cladding (UVA-LC)
Laser cladding (LC) yog cov cuab yeej tseem ceeb rau kev ntxiv dag zog rau saum npoo, tab sis cov tsoos LC yog qhov ua rau "tsis sib npaug ntawm cov theem ntxiv zog" thiab "cracking." UVA-LC, los ntawm kev tswj hwm ultrasonic, ua tiav kev txhim kho ob qho tib si "hardness thiab hnav tsis kam" ntawm txheej cladding.
3.1 Apparatus Design: Resonance Matching ntawm Ultrasonic System
Lub UVA-LC system yuav tsum ua kom tau raws li qhov sib piv ntawm "ultrasonic system - substrate - molten pas" (Daim duab 15, 16):
Ultrasonic zaus: Feem ntau 20 kHz, qhov ntev ntawm ultrasonic amplitude transformer yog optimized los ntawm modal tsom xam (115-130 hli) kom ntseeg tau zoo hloov ntawm vibration zog mus rau lub pas dej ua ke molten;
Substrate tsim: Ib "ib nrab-wavelength qauv" yog saws (Daim duab 16), thiab finite element simulation (ANSYS) yog siv los xyuas kom meej tias lub substrate resonance zaus sib tw nrog ultrasonic zaus (yuam kev <1%).
