Rau qhov kub nias, qhov tswj tau qhov sib txawv ntawm qhov ntsuas kub thiab ntsuas kub yog siv. Feem ntau, lub siab raug thov tom qab qee qhov cua sov tau tshwm sim vim hais tias thov kev tso siab ntawm qhov kub qis dua tuaj yeem muaj qhov tsis zoo ntawm ntu thiab ntu. Kub nias kub yog ob peb puas qib qis dua li niaj zaus sintering kub. Thiab yuav luag tag nrho cov densification tshwm sim sai. Kev ceev ntawm cov txheej txheem raws li qis dua qhov kub yuav tsum tau txwv ib txwm muaj nuj nqis ntawm cov noob qoob loo tuaj.
Lwm txoj kev cuam tshuam, tawg plasma sintering (SPS), muab lwm txoj hauv kev rau sab nraud kev tiv thaiv thiab hom kev hloov ua cua sov. Hauv SPS, tus qauv, feem ntau yog hmoov lossis ib qho kev npaj ua ntsuab, yog thauj hauv graphite tuag nrog graphite punches hauv lub tshuab nqus tsev thiab qhov pulsed DC tam sim no yog thov hla kev xuas nrig, zoo li pom hauv daim duab 5.35b, thaum lub siab thov. Qhov tam sim no ua rau Joule cua sov, uas ua kom qhov kub ntawm lub nrws sai sai. Qhov tam sim no tseem ntseeg tau tias yuav tsim teeb meem ntshav lossis txim hluav taws xob hauv qhov chaw pore nruab nrab ntawm qhov me me, uas muaj kev cuam tshuam ntawm kev ua kom huv ntawm cov ntu thiab txhim kho kev ua txhaum. Lub plasma tsim yog qhov nyuaj rau kev kuaj pom tseeb thiab yog cov ncauj lus sib cav. SPS txoj kev qhia tau pom tias muaj txiaj ntsig zoo rau qhov kev densification ntawm ntau cov khoom siv, suav nrog cov hlau thiab ceramics. Densification tshwm sim nyob rau hauv qis kub thiab ua tiav sai dua li ntawm lwm txoj kev, feem ntau ua rau zoo lis microstructures.
Kub Isostatic Pressing (HIP). Kub isostatic nias yog ib qho kev siv hluav taws xob thaum tshav kub kub thiab hydrostatic siab kom ua kom nruj thiab densify cov hmoov compact lossis ib feem. Cov txheej txheem yog sib piv rau txias isostatic nias, tab sis nrog cov cua kub nce thiab cov roj xa cov siab mus rau cov ntu. Inert gases xws li argon muaj ntau. Cov hmoov ua kom nruj dua hauv cov thawv lossis lub peev xwm, uas ua raws li qhov cuam tshuam tsis zoo ntawm qhov cov roj pa thiab cov ntu. Xwb, ib qho uas tau ua tiav thiab muab kho kom mus txog thaum pore kaw tau HIPed nyob rau hauv “tsis muaj thawv” cov txheej txheem. HIP yog siv los ua tiav cov txheej txheem densification hauv cov hmoov metallurgy. thiab cov ua ceramic, nrog rau qee qhov kev thov hauv qhov densification ntawm castings. Cov txheej txheem tshwj xeeb yog qhov tseem ceeb rau qhov nyuaj rau cov ntaub ntawv ntau, xws li cov khoom siv refractory alloys, superalloys, thiab nonoxide ceramics.
Thawv thiab encapsulation thev naus laus zis yog qhov tseem ceeb rau HIP txheej txheem. Cov ntim khoom ntim tau yooj yim, xws li cov hlau ntim uas muaj hlau kheej kheej, yog siv los ua cov paib ntawm cov hmoov sib xyaw. Cov duab tsis sib luag yog tsim los siv cov ntim uas tsom iav qhov kawg ntawm geometries. Cov thawv ntim khoom yog xaiv los ua xeb-ntuag thiab deformable nyob rau hauv lub siab thiab ntsuas kub ntawm cov txheej txheem HIP. Cov thawv ntim khoom kuj yuav tsum ua kom tsis zoo nrog cov hmoov thiab tshem tawm yooj yim. Rau hmoov metallurgy, ntim kev zam los ntawm cov hlau pob yog qhov ntau. Lwm cov kev xaiv muaj xws li iav thiab cov dej txeem uas txig rau hauv cov theem nrab hlau tau. Iav encapsulation ntawm cov hmoov thiab cov tshooj ua ntej yog feem ntau hauv cov txheej txheem ceramic HIP. Kev ntim thiab tshem tawm ntawm cov thawv yog cov kauj ruam tseem ceeb uas feem ntau xav tau tshwj xeeb tshaj tawm ntawm cov thawv ntim nws tus kheej. Qee qhov txheej txheem khiav tawm mus rau qhov ntsuas kub.
Cov khoom tseem ceeb ntawm cov kab ke rau HIP yog lub nkoj siab nrog lub ua cua sov, roj cua ua pa thiab xuas tes ua haujlwm, thiab tswj cov khoom siv hluav taws xob. Daim duab 5.36 qhia tawm piv txwv schematic ntawm HIP kev teeb tsa. Nws muaj ob txoj haujlwm yooj yim ntawm kev ua haujlwm rau HIP txheej txheem. Nyob rau hauv qhov chaw thau khoom kub, cov thawv ntim tau preheated sab nraud ntawm lub nkoj siab thiab tom qab ntawd thauj khoom, kho kom sov mus rau qhov ntsuas kub uas yuav tsum tau ua thiab nias kom hnyav. Hauv qhov chaw thau khoom txias, cov thawv ntim tso rau hauv lub nkoj siab ntawm chav sov; tom qab ntawd cov cua kub thiab pa luam tawm pib. Siab nyob rau hauv thaj tsam ntawm 20-300 MPa thiab qhov kub thiab txias ntawm thaj tsam ntawm 500-2000 ° C yog qhov ntau.
Sijhawm post: Nov-17-2020