Nyob rau hauv cov txheej txheem ntawm smelting los yog kub ua hauj lwm ntawm hlau, vim muaj tej yam (xws li non-metallic inclusions, gases, txheej txheem xaiv los yog ua hauj lwm tsis zoo, thiab lwm yam).Defects sab hauv los yog nyob rau saum npoo ntawm lubseamless steel yeeb nkabyuav cuam tshuam rau qhov zoo ntawm cov khoom lossis cov khoom, thiab qee zaum ua rau cov khoom lossis cov khoom raug muab pov tseg.
Porosity, npuas, shrinkage crater residues, non-metallic inclusions, segregation, dawb me ntsis, tawg thiab ntau yam txawv txav tsis xws luag nyob rau hauvtxias kos seamless steel kavtuaj yeem pom los ntawm kev tshuaj xyuas macroscopic.Muaj ob txoj hauv kev tshuaj xyuas macro: acid leaching tshuaj xyuas thiab tshuaj xyuas pob txha.Cov teeb meem macroscopic uas tshwm sim los ntawm acid leaching yog piav qhia luv luv hauv qab no:
1. Kev cais tawm
Ua rau ntawm kev tsim: Thaum lub sij hawm casting thiab solidification, qee cov ntsiab lus sib sau ua ke vim xaiv crystallization thiab diffusion, ua rau cov tshuaj tsis sib xws.Raws li txoj haujlwm sib txawv, nws tuaj yeem muab faib ua hom ingot, nruab nrab cais thiab taw tes cais.
Macroscopic nta: Ntawm cov kua qaub leaching cov qauv, thaum muab cais rau hauv cov khoom siv corrosive lossis cov pa roj, cov xim yog tsaus, cov duab tsis zoo, me ntsis concave, hauv qab yog tiaj, thiab muaj ntau cov ntsiab lus ntom microporous.Yog hais tias cov khoom tiv thaiv aggregates, nws yuav yog lub teeb-xim, irregularly zoo li tus, kuj du microbump.
2. xoob
Ua rau ntawm kev tsim: Thaum lub sij hawm solidification txheej txheem, cov hlau tsis tuaj yeem welded thaum lub sij hawm ua hauj lwm kub vim qhov kawg solidification shrinkage ntawm cov khoom uas tsis tshua muaj melting point thiab tso tawm roj los tsim voids.Raws li lawv qhov kev faib tawm, lawv tuaj yeem muab faib ua ob pawg: hauv nruab nrab xoob thiab dav dav.
Cov yam ntxwv ntawm macroscopic: Nyob rau sab nraud kub acid leaching nto, qhov pores yog tsis xwm yeem polygons thiab pits nrog nqaim hauv qab, feem ntau ntawm qhov sib cais.Nyob rau hauv cov xwm txheej hnyav, muaj kev nyiam sib txuas rau hauv ib qho spongy zoo li.
3. Kev suav nrog
Formation vim li cas:
① Txawv teb chaws hlau suav nrog
Yog vim li cas: Thaum lub sij hawm pouring txheej txheem, hlau tuav, hlau blocks thiab hlau los xij poob rau hauv cov pwm ingot, los yog cov hlau alloy ntxiv rau qhov kawg ntawm lub smelting theem tsis melted.
Macroscopic nta: Ntawm cov ntawv etched, feem ntau cov duab geometric nrog cov npoo ntse thiab cov xim sib txawv ntawm ib puag ncig.
② Txawv teb chaws non-metallic inclusions
Yog vim li cas: Thaum lub sij hawm pouring txheej txheem, cov khoom refractory ntawm lub qhov cub hauv ob sab phlu thiab lub puab phab ntsa ntawm lub pouring system tsis ntab los yog tev tawm mus rau hauv lub molten hlau.
Cov yam ntxwv ntawm Macroscopic: Cov hlau tsis muaj hlau loj dua tuaj yeem txheeb xyuas tau yooj yim, thaum cov khoom me me corrode thiab tev, tawm hauv qhov me me.
③ Tig daim tawv nqaij
Ua rau ntawm kev tsim: Cov hlau molten muaj cov yeeb yaj kiab semi-kho rau ntawm qhov chaw hauv qab.
Cov yam ntxwv ntawm macroscopic: Cov xim ntawm cov kua qaub leaching qauv txawv ntawm ib puag ncig, thiab cov duab yog qhov tsis xwm yeem nkhaus nqaim strips, thiab feem ntau muaj oxide inclusions thiab pores nyob ib ncig ntawm.
4. Txo
Ua rau ntawm kev tsim: Thaum casting ib qho ingot los yog casting, cov kua hauv cov tub ntxhais tsis tuaj yeem rov ua dua vim qhov ntim ntim thaum lub sij hawm kawg condensation, thiab lub taub hau ntawm lub ingot los yog casting ua ib kab noj hniav macroscopic.
Macroscopic nta: Lub shrinkage kab noj hniav nyob rau hauv nruab nrab ntawm cov tom qab acid leached qauv, thiab cov cheeb tsam ib puag ncig feem ntau yog cais, sib tov los yog xoob.Qee lub sij hawm lub qhov los yog cov kab nrib pleb tuaj yeem pom ua ntej etching, thiab tom qab etching, qhov chaw ntawm lub qhov tsaus thiab zoo li cov qhov tsis sib xws.
5. Npuas
Ua rau tsim: Cov teeb meem tshwm sim los ntawm gases generated thiab tso tawm thaum lub sij hawm ingot casting.
Macroscopic Nta: Hloov cov qauv nrog cov kab nrib pleb roughly perpendicular rau saum npoo nrog me ntsis oxidation thiab decarburization nyob ze.Lub xub ntiag ntawm subcutaneous cua npuas hauv qab no yog hu ua subcutaneous cua npuas, thiab tob subcutaneous cua npuas yog hu ua pinholes.Thaum lub sij hawm forging txheej txheem, cov unoxidized thiab unwelded qhov txuas mus rau hauv nyias hlab nrog cais me me pinholes nyob rau hauv hla ntu.Lub hlaws zoo li cov ntsiab lus sib cais tsis tu ncua, tab sis cov xim tsaus yog cov npuas hauv cov honeycomb.
6. Vitiligo
Ua rau ntawm kev tsim: Nws yog feem ntau suav hais tias yog kev cuam tshuam ntawm hydrogen thiab cov txheej txheem kev ntxhov siab, thiab kev sib cais thiab kev suav nrog hauv cov hlau kuj muaj qee yam cuam tshuam, uas yog hom tawg.
Cov yam ntxwv macroscopic: luv luv, nyias tawg ntawm transverse kub acid leached kuaj.Muaj qhov kaj dawb ntawm cov nyiaj ntxhib-grained ntawm qhov ntev ntawm qhov tawg.
7. Ncua tseg
Tsim vim: axial intergranular tawg.Thaum cov qauv dendritic hnyav heev, cov kab nrib pleb yuav tshwm sim raws cov ceg loj thiab nruab nrab ntawm cov ceg ntawm cov pob zeb loj loj.
Cov kab nrib pleb sab hauv: Cov kab nrib pleb tshwm sim los ntawm kev ua tsis zoo forging thiab dov txheej txheem.
Cov yam ntxwv ntawm macroscopic: Ntawm qhov hla ntu, txoj hauj lwm axial tawg raws lub intergranular, nyob rau hauv cov duab ntawm kab laug sab web, thiab radial cracking tshwm sim nyob rau hauv mob hnyav.
8. Quav
Ua rau tsim: tsis sib xws nto nti ntawmtxias-draw carbon steel tubelos yog steel ingots thaum lub sij hawm forging thiab dov, ntse npoo thiab cov ces kaum overlapped rautxias-draw seamless steel raj, los yog pob ntseg zoo li cov khoom tsim vim tsis tsim nyog dhau kev tsim lossis kev ua haujlwm, thiab txuas ntxiv dov.superimposed thaum lub sij hawm tsim khoom.
Cov yam ntxwv ntawm macroscopic: Nyob rau ntawm qhov hloov pauv kub acid dipping qauv ntawm cov yeeb nkab txias seamless steel yeeb nkab, muaj oblique tawg ntawm cov hlau, thiab muaj decarburization hnyav nyob ze, thiab qhov tawg feem ntau muaj oxide nplai.
Post lub sij hawm: Nov-02-2022