Lub hardness ntawm hlau 3D tshuab luam ntawv tuaj yeem ua tau raws li qhov yuav tsum tau ua rau siab - lub zog ntau lawm?

1. Xaiv cov khoom tsim nyog: Kev txhawb nqa hauv qab yog ua los ntawm cov hmoov hlau nrog lub siab toughness
Cov khoom nws tus kheej txiav txim siab npaum li cas hlau 3D luam ntawv pwm yog. Cov cuab yeej hlau, stainless hlau, tawv alloys, thiab tshwj xeeb alloys yog cov khoom siv tshaj plaws rau 3D luam ntawv pwm tam sim no. Lawv muaj qhov nyuaj ntawm HRC 20 txog 70, uas txhais tau hais tias lawv tuaj yeem siv tau rau ntau qhov xwm txheej.
Cov cuab yeej hlau, zoo li H13 thiab A2, muaj qhov nyuaj ntawm HRC 40-60 tom qab kev kho cua sov. Nws muaj zog thiab tiv taus hnav, ua rau nws zoo rau siab - kev ntxhov siab xws li tuag- casting pwm thiab kub forging pwm. Piv txwv li, ib lub tuam txhab uas ua rau lub tsheb qhov chaw ntiav 3D luam H13 steel pwm uas yog HRC 52 nyuaj tom qab kev kho cua sov. Cov pwm no ua haujlwm ib yam li cov pwm forging ib txwm siv thiab siv sijhawm ntev dua peb zaug.
316L stainless hlau muaj ib tug hardness ntawm HRC 20-30, tab sis los ntawm kev kho cov printing chaw thiab post- ua, nws hardness yuav raug tsa mus rau ntau tshaj HRC 40 thaum tseem yog heev resistant rau corrosion. Qhov no ua rau nws zoo rau thaj chaw uas kev nyiam huv tseem ceeb heev, xws li ntim khoom noj thiab khoom siv kho mob.
Hard alloy: WC Co (tungsten carbide cobalt) yog cov khoom siv rau cov xwm txheej hnyav xws li xuas nrig ntaus tuag thiab kos duab tuag. Nws muaj qhov nyuaj txog li HRC 55-70 thiab ntau dua 10 npaug ntau dua hnav-tiv taus dua li cov cuab yeej hlau. Ib lub tuam txhab uas ua rau cov khoom siv hluav taws xob ua haujlwm 3D- luam tawm cov pwm muaj zog ua rau ob npaug ntawm qhov xuas nrig ntaus, los ntawm 500,000 npaug rau 2 lab lub sijhawm.
3D printing can make fine-grained structures in special alloys like Inconel 718 nickel-based alloy. These structures are 20% harder than those made by traditional casting. They also stay strong at high temperatures (strength retention rate>90% ntawm 650 degree), uas yog vim li cas lawv tau siv ntau hauv pwm rau aviation cav turbine discs.
2. Txheej txheem optimisation: meej tswj los ntawm "printing" mus rau "forming"
Lub hardness ntawm hlau Tsis yog cov khoom siv xwb tab sis kuj tseem muaj kev tswj xyuas qhov tseeb ntawm cov txheej txheem tsis tseem ceeb rau 3D luam ntawv. Piv txwv li, xaiv laser melting (SLM) tshuab nce hardness los ntawm optimizing cov nram qab no tseem ceeb tsis:
Control of energy density: The quality of the molten pool is directly affected by the strength of the laser, the speed of the scan, and the size of the spot. When the energy density is low, the material may become more porous (15% less hard when>1%), thiab thaum nws siab, nws yuav tawg. Txoj kev tshawb no qhia tau hais tias thaum luam ntawv 316L stainless hlau nrog lub zog laser ntawm 150W thiab scanning ceev ntawm 800mm / s, lub porosity nyob qis dua 0.3% thiab hardness mus txog HRC 38, uas yog yuav luag tib yam li forgings.
Interlayer bonding zog: Ib qho kev sib txuas ntawm cov hlau nplaum muaj zog ntawm cov txheej txheem tuaj yeem ua los ntawm kev hloov cov txheej txheem scanning (xws li chequerboard scanning thiab kob scanning) thiab txheej thickness (20-50 μ m). Piv txwv li, ib qho kev lag luam aviation luam tawm Ti6Al4V turbine hniav pwm nrog txheej thickness ntawm 30 μm thiab interlayer bonding zog ntawm 450MPa, uas yog 20% ​​muaj zog dua li yav dhau los txoj kev.
Setting the cooling rate: Rapid cooling (>10 ^ 4℃/ s) tuaj yeem tsim cov qauv zoo -grained qauv (xws li martensite) uas ua rau cov khoom hnyav dua. Siv L-PBF thev naus laus zis, pab pawg hauv nroog University of Hong Kong tau luam tawm Al Mg Mn Sc Zr alloy. Lawv siv lub nano ntxaib ntxiv dag zog rau kev txhawb nqa lub zog tawm mus rau 656MPa thaum khaws cov ductility ntawm 12%.
3. Tshaj tawm- txheej txheem thev naus laus zis: kauj ruam kawg ntawm kev ua kom tawv tawv zoo dua
3D luam ntawv tsis yog qhov kawg; post-txoj kev siv tshuab yog qhov tseem ceeb tshaj plaws ntawm kev ua pwm nyuaj.
Kev kho cua sov: hloov cov qauv lattice los ntawm annealing, quenching, lossis laus. Piv txwv li, tom qab muaj hnub nyoog ntawm 480 degree, lub hardness ntawm 3D luam tawm 18Ni300 martensitic aging steel pwm mus los ntawm HRC 38 mus rau HRC 52. Qhov no tau tshem ntawm kev ntxhov siab thiab ua rau nws tsis tshua muaj kev tawg.
Txhawm rau ua kom lub ntsej muag nyuaj, koj tuaj yeem siv tshuaj tua kab mob, nitriding, lossis laser cladding. Ib qho kev tuag-casting pwm txiag ua hauj lwm txhaj tshuaj peening rau 3D luam H13 steel pwm. Qhov no ua rau saum npoo nyuaj (los ntawm HRC 50 rau HRC 58) thiab ua rau lawv 40% tiv taus hnav.
Kub isostatic nias (HIP): Siv lub siab siab (100-200 MPa) thiab kub siab (900-1200 degree) kom tshem tawm cov pores sab hauv thiab tau txais cov khoom ntom ntom ze rau 100%. Inconel 718 pwm uas tau kho nrog HIP yog 30% nyuaj thiab kav tsib zaug ntev dua cov pwm uas tsis kho.
4. Kev lag luam siv: kev sim los ntawm kev sim mus rau cov kab tsim khoom
Cov txiaj ntsig hardness ntawm hlau 3D luam ntawv pwm tau lees paub hauv ntau qhov chaw:
GE Aviation siv 3D- luam tawm Inconel 718 roj nozzle pwm nrog lub hardness ntawm HRC 45. Cov pwm no yog 15% sib zog dua li cov qauv castings thiab tuaj yeem tswj tau qhov kub thiab txias.
Ua tsheb: BMW Group ua txhuas alloy cav lub tog raj kheej thaiv siv steel pwm thiab 3D tshuab luam ntawv. Cov pwm hardness yog HRC 50, thiab nws kav ntau tshaj 100,000 zaug, uas txo tus nqi ntawm txhua daim los ntawm 40%.
Johnson & Johnson ntiav 3D- luam tawm cobalt chromium alloy orthopedic cog pwm uas yog HRC 60 nyuaj thiab Ra<0.2 μ m rough on the surface. These moulds meet both biocompatibility and wear resistance standards.