Cov ntaub ntawv hlau ua lub luag haujlwm tseem ceeb hauv kev lag luam niaj hnub thiab lub neej niaj hnub, thiab lawv qhov kev ua tau zoo yog ncaj qha cuam tshuam rau qhov zoo thiab kev nyab xeeb ntawm cov khoom. Ntawm lawv, cuam tshuam toughness, raws li qhov tseem ceeb ntawm kev ua tau zoo ntawm cov khoom siv hlau, qhia txog lub peev xwm ntawm cov ntaub ntawv los tiv thaiv kev puas tsuaj thiab rov qab deformation thaum raug cuam tshuam los ntawm kev thauj khoom. Hauv daim ntawv no, peb yuav tham txog ntau yam cuam tshuam rau qhov cuam tshuam ntawm cov khoom siv hlau, txhawm rau muab kev siv rau kev xaiv, kev ua haujlwm thiab kev ua haujlwm zoo ntawm cov ntaub ntawv.
Ua ntej, cov qauv sab hauv thiab lub koom haum ntawm cov ntaub ntawv
Metallographic qauv ntawm cov ntaub ntawv hlau muaj qhov cuam tshuam loj rau nws qhov cuam tshuam toughness. Grain refinement thiab lub koom haum homogenisation yog ib txoj kev zoo los txhim kho toughness ntawm cov ntaub ntawv. Grain refinement tuaj yeem ua rau muaj ntau ntawm cov ciam teb, yog li cuam tshuam kev nthuav dav ntawm cov kab nrib pleb thiab txhim kho cov pob txha toughness ntawm cov khoom. Cov ntaub so ntswg homogenisation txo cov teeb meem sab hauv xws li suav nrog, sib cais, npuas thiab cov kab nrib pleb sab hauv, uas feem ntau yog lub hauv paus ntawm kev pib tawg thiab txuas ntxiv, thiab txo qhov cuam tshuam ntawm cov khoom.
Tsis tas li ntawd, cov theem muaj pes tsawg leeg ntawm cov khoom siv hlau kuj tseem muaj txiaj ntsig zoo rau nws qhov toughness. Piv txwv li, qhov siab dua cov ntsiab lus ntawm ferrite, ib theem uas tsis muaj zog, zoo plasticity thiab toughness, qhov zoo dua qhov cuam tshuam toughness ntawm cov khoom feem ntau yog. Ntawm qhov tsis sib xws, reticulated carburites deteriorate lub toughness ntawm cov khoom, thiab ntau dua lawv cov nyiaj, qhov cuam tshuam qhov hnyav ntawm cov khoom. Yog li, los ntawm kev kho cov tshuaj muaj pes tsawg leeg ntawm cov khoom thiab cov txheej txheem kev kho cua sov, cov theem muaj pes tsawg leeg tuaj yeem tswj tau, thiab yog li qhov cuam tshuam toughness ntawm cov khoom tuaj yeem ua kom zoo dua.
Qhov thib ob, cov tshuaj muaj pes tsawg leeg
Cov tshuaj lom neeg muaj pes tsawg leeg ntawm cov ntaub ntawv hlau muaj qhov cuam tshuam tsis zoo rau nws qhov cuam tshuam toughness. Cov pa roj carbon, phosphorus, sulfur thiab lwm cov ntsiab lus ntawm cov ntsiab lus nce, feem ntau ua rau txo qis ntawm qhov cuam tshuam toughness ntawm cov khoom. Qhov no yog vim hais tias cov ntsiab lus no yog ib qho yooj yim los tsim nkig theem los yog inclusions nyob rau hauv cov khoom, ua kom muaj kev ntxhov siab concentration thiab txo cov toughness ntawm cov khoom.
Txawm li cas los xij, tsis yog tag nrho cov ntsiab lus tsis zoo cuam tshuam qhov toughness ntawm cov khoom. Piv txwv li, cov ntsiab lus manganese (Mn) thiab npib tsib xee (Ni) muaj txiaj ntsig zoo hauv kev txhim kho qhov tawv ntawm cov ntaub ntawv rau qee qhov: Mn refines cov nplej thiab inhibits nag lossis daus ntawm carbides raws li cov ciam teb, thaum Ni nce lub zog txheej ntawm ferrite thiab txhawb nqa kev hla kev tsiv teb tsaws ntawm dislocations, uas ua rau muaj zog ntawm cov hlau.
III. Kev kho cua sov txheej txheem
Cov txheej txheem kho cua sov muaj qhov cuam tshuam tseem ceeb ntawm microstructure thiab cov khoom ntawm cov khoom siv hlau. Los ntawm kev kho cua sov kom tsim nyog, tuaj yeem ua kom zoo dua cov nplej, tshem tawm kev ntxhov siab, txhim kho cov txheej txheem, yog li txhim kho cov tawv nqaij ntawm cov khoom. Piv txwv li, cov txheej txheem kev kho cua sov ntawm Quenching thiab Tempering tuaj yeem tsim lub koom haum tawv xws li tempered martensite, uas ua rau muaj kev cuam tshuam zoo ntawm cov khoom.
Txawm li cas los xij, cov txheej txheem kev kho cua sov kuj tseem tuaj yeem tsim cov kev hloov pauv tsis zoo, xws li overheating thiab overcooking, uas tuaj yeem ua rau txo qis ntawm cov khoom siv. Yog li ntawd, nyob rau hauv txoj kev loj hlob ntawm cov txheej txheem kev kho cua sov, nws yog ib qhov tsim nyog yuav tau coj mus rau hauv tus account lub muaj pes tsawg leeg ntawm cov khoom, lub koom haum qauv thiab cov kev xav tau ntawm kev ua tau zoo los xyuas kom meej tias qhov zoo tshaj plaws toughness kev ua tau zoo.
Plaub, cov txheej txheem ua
Kev ua cov khoom siv hlau, xws li forging, dov, thiab lwm yam, yuav ua rau muaj kev ntxhov siab thiab deformation hauv cov khoom. Cov kev ntxhov siab no yuav cuam tshuam rau qhov toughness ntawm cov khoom mus rau ib qho twg. Piv txwv li, nyob rau hauv cov txheej txheem dov, hlau inclusions nrog hlau nplej raws lub ntsiab deformation kev taw qhia yog elongated, tsim cov hlau fiber ntau lub koom haum, lub koom haum no yuav txo tau qhov cuam tshuam toughness ntawm cov khoom.
Txhawm rau txo qhov cuam tshuam ntawm kev ua haujlwm ntawm cov khoom siv tawv, nws yog ib qho tsim nyog yuav tsum xaiv cov txheej txheem txheej txheem thiab cov txheej txheem tsis zoo. Piv txwv li, nyob rau hauv cov txheej txheem dov, koj tuaj yeem kho qhov kub dov, qhov qis qis thiab lwm yam tsis zoo los tswj cov qib ntawm deformation ntawm cov khoom thiab cov kev ntxhov siab sab hauv, thiaj li ua kom zoo dua qhov kev ua tau zoo ntawm cov khoom toughness.
Thib tsib, tus qauv orientation thiab notch effect
Kev taw qhia ntawm cov khoom siv hlau yuav cuam tshuam rau nws cov khoom siv kho tshuab, suav nrog toughness. Piv txwv li, raws li cov kev taw qhia dov ntawm cov qauv, vim muaj cov hlau fiber ntau cov ntaub so ntswg, qhov cuam tshuam toughness ntawm cov khoom feem ntau yog loj dua. Conversely, thaum sampling perpendicular mus rau dov kev taw qhia, qhov cuam tshuam toughness ntawm cov khoom yog me me.
Tsis tas li ntawd, qhov kev cuam tshuam ntawm qhov taw qhia yog ib qho tseem ceeb cuam tshuam rau qhov cuam tshuam toughness ntawm cov khoom. Notching ua rau kev ntxhov siab concentration, uas txo cov toughness ntawm cov khoom. Notch geometry, qhov loj me thiab machining zoo tag nrho muaj qhov cuam tshuam rau qhov cuam tshuam toughness ntawm cov khoom. Piv txwv li, V-notches muaj qhov siab dua ntawm kev ntxhov siab piv rau U-notches thiab yog li ntawd lawv cov kev cuam tshuam toughness feem ntau qis dua. Txhawm rau txhim kho qhov cuam tshuam ntawm cov khoom siv, qhov kev coj ua piv txwv, cov duab kos thiab kev ua haujlwm zoo ntawm cov qauv yuav tsum tau tswj nruj me ntsis.
VI. Cov xwm txheej kuaj
Cov xwm txheej xeem kuj yog ib qho tseem ceeb cuam tshuam rau qhov cuam tshuam toughness ntawm cov ntaub ntawv hlau. Ntawm lawv, qhov ntsuas kub muaj qhov cuam tshuam loj rau qhov cuam tshuam toughness ntawm cov khoom. Raws li qhov kub thiab txias, qhov cuam tshuam toughness ntawm cov khoom feem ntau txo qis. Qhov no yog vim hais tias cov yas deformation muaj peev xwm ntawm cov khoom raug txo qis ntawm qhov kub thiab txias, thiab qhov tawg txuas ntxiv nrawm nrawm, uas ua rau txo qhov tawv.
Tsis tas li ntawd, cov yam ntxwv xws li qhov tseeb ntawm lub tshuab kuaj thiab qhov haum ntawm lub pendulum rau lub thav duab kuj muaj qhov cuam tshuam rau qhov cuam tshuam ntawm cov khoom siv. Yog li ntawd, nyob rau hauv qhov kev ntsuam xyuas toughness, yuav tsum tau xyuas kom meej tias qhov precision thiab stability ntawm lub tshuab kuaj kom tau raws li qhov yuav tsum tau, thiab nruj raws li cov qauv tsim nyog rau kev xeem.
Xya, tsis xws luag thiab impurities
Qhov tsis xws luag thiab impurities nyob rau hauv cov khoom siv hlau kuj yog ib qho tseem ceeb uas cuam tshuam rau nws cov kev cuam tshuam toughness. Qhov tsis xws luag thiab impurities yuav ua rau muaj kev ntxhov siab ntau ntxiv thiab txo qhov toughness ntawm cov khoom. Piv txwv li, inclusions, npuas thiab lwm yam tsis xws luag sab hauv tuaj yeem ua rau tawg pib thiab nthuav, yog li txo qhov cuam tshuam ntawm cov khoom siv.
Txhawm rau txo qhov cuam tshuam ntawm qhov tsis xws luag thiab impurities ntawm cov khoom toughness, qhov zoo ntawm raw cov ntaub ntawv thiab cov txheej txheem ntau lawm yuav tsum tau tswj nruj me ntsis thaum lub sij hawm npaj thiab ua cov khoom. Piv txwv li, los ntawm refining, degassing thiab lwm yam txheej txheem yuav txo tau cov khoom inclusions thiab npuas thiab lwm yam tsis xws luag; los ntawm cov txheej txheem kev kho cua sov tsim nyog tuaj yeem tshem tawm lossis txo cov kev ntxhov siab thiab kev ua haujlwm tsis zoo hauv cov khoom siv.
Cov yam ntxwv cuam tshuam rau qhov cuam tshuam ntawm cov khoom siv hlau yog ntau qhov sib txawv, suav nrog cov qauv sab hauv thiab lub koom haum ntawm cov khoom siv, tshuaj lom neeg muaj pes tsawg leeg, txheej txheem kev kho cua sov, kev siv thev naus laus zis, kev taw qhia cov qauv thiab cov txiaj ntsig tsis zoo, cov xwm txheej kuaj, nrog rau qhov tsis xws luag thiab impurities. Los ntawm kev txiav txim siab txog cov xwm txheej no thiab siv cov kev ntsuas kom zoo, qhov cuam tshuam ntawm cov khoom siv hlau tuaj yeem txhim kho kom tau raws li qhov xav tau ntawm ntau yam kev siv hauv kev lag luam.
