High yield zog thiab tensile plasticity yog qhov tseem ceeb rau kev siv engineering ntawm cov khoom siv hlau. Tam sim no, tsuas yog ob peb lub ultra- siab- lub zog steels ua tiav lub zog loj (σy) ntawm 2 GPa. Txawm li cas los xij, lawv tsis muaj peev xwm ua haujlwm txaus thaum lub sij hawm yas deformation, uas ua rau lub cev deformation qhia nyob rau hauv cov qauv uniaxial tensile kev ntsuam xyuas yog tsim los ntawm serrated yas ntws los ntawm localized deformation bands, es tsis muaj tseeb uniform elongation (ɛu). Cov no ultra-siab- lub zog steels, xws li maraging steels, feem ntau muaj qis heev elongation (piv txwv li, ɛu ~ 5%). Txawm hais tias qhov thib ob classic-theem ntxiv zog mechanism tuaj yeem txhim kho lub zog ntawm cov khoom siv, qhov kev txhawb zog yog txwv los ntawm qhov qis qis ntawm theem thib ob hauv cov hlau (feem ntau < 50 vol.%), ua rau muaj qhov txo qis hauv tensile plasticity. Yog li ntawd, tsim cov alloys nrog ob lub zog tawm los σy ~ 2 GPa thiab ib qho elongation zoo li ntau dua 10% yog qhov kev sib tw loj hauv cov ntaub ntawv tshawb fawb.
Nyob rau hauv kev teb rau cov kev cov nyom saum toj no, xibfwb Zhang Jinyu, xibfwb Ma En, thiab Academician Sun Jun los ntawm National Key Laboratory of Metal Material Strength ntawm Xi'an Jiaotong University tau thov kom siv ultra-siab ntim feem ntau intermetallic compound precipitates, uas yog coherent L12 nano theem thiab tsis muaj coherent low micro modulus zog ob peb theem B2. FCC nplua nuj hlau complex alloy matrix raws li lawv cov kev ua tiav dhau los (Acta Mater, 2022, 233: 117981; Scripta Mater, 2023, 222: 115058). Txhawm rau kom ua tiav ultra{10}}lub zog siab thiab lub zog loj tensile ductility nyob rau hauv chav tsev kub, lub tswv yim tsim ntawm no alloy yog: i) kom nws lub zog muaj zog nrog ib tug siab ntim feem ntawm coherent L12 nano theem nrog siab inversion domain ciam teb zog, thiab ii) los qhia ib tug siab ntim feem ntawm tsawg modulus tsis coherent B2 micro theem; Ntawm qhov tod tes, kev sib txuas lus tsis sib xws yog qhov ua tau zoo dua hauv kev cuam tshuam kev txav mus los thiab txhim kho cov txiaj ntsig zoo dua li kev sib txuas lus sib txuas. Ntawm qhov tod tes, cov kev taw qhia ntawm ntau yam alloying ntsiab txo qhov kev tiv thaiv theem ntawm ciam teb ntawm B2 kom nws cov plasticity, tso cai rau cov hais los ua dislocation cia units thiab txhim kho kev ua hauj lwm hardening peev xwm.
Lub tswv yim tsim ntawm ntau lub ntsiab tseem ceeb alloys ua rau muaj kev xaiv ntau qhov chaw rau cov alloys nyuaj, uas ua rau muaj teeb meem tsis tau muaj dua los rau kev tsim cov qib siab -kev ua tau zoo alloys raws li cov txheej txheem "sim thiab yuam kev". Txog qhov kawg no, cov tswv cuab hauv pab pawg tau soj ntsuam cov khoom siv los ntawm kev paub txog kev paub siv tshuab kev kawm. Lub ntsiab tseem ceeb tshaj plaws Ta (tsis yog lub ntsiab Ti) synergistic alloying tau ua tiav los ntawm cov khoom siv siab solubility lub teeb Al thiab L12 cov theem sib txawv ntawm thaj tsam, ua rau L12+B2 dual nag lossis daus theem ntxiv dag zog rau Fe35Ni29Co21Al12Ta3 (at.%) complex alloy (Daim duab 1). Qhov ntim feem ntawm L12 nano theem (nplua nuj nyob rau hauv Al, Ta) thiab B2 micro theem (nplua nuj nyob rau hauv Al, pluag nyob rau hauv Ta) yog siab li ~ 67 vol.% thiab ~ 15 vol.%, feem. Ob qho tib si L12 / FCC interface thiab qhov tsis sib xws B2 / FCC interface tuaj yeem cuam tshuam nrog kev cuam tshuam (Daim duab 2). Not only can it generate dislocations, but it can also store dislocations, especially the low modulus B2 micron phase can be compared to (FCC+L12) The higher density of dislocations stored in the matrix (Figure 3) significantly enhances the work hardening performance of the alloy, thereby improving its yield/tensile strength and tensile ductility, enabling the alloy to achieve an unprecedented zog plasticity kev sib xyaw ua ke ntawm chav tsev kub, zoo dua li txhua qhov kev qhia alloys rau hnub tim (Daim duab 4). Lub tswv yim tsim cov hlau nplaum uas tau npaj los ntawm pab pawg kuj tseem muab cov tswv yim tshiab rau kev tsim ntawm lwm cov qib siab -kev ua tau zoo alloys.
Daim duab 1. (a) Tus qauv kev paub raws li tshuab kev kawm (muaj rau 6 lub voj voog kev kawm) kwv yees cov FeNiCoAlTa complex alloy nrog super plasticity. (b) Lub theoretical kwv yees lub zog muaj zog yog ua raws li qhov kev sim ntsuas qhov muaj zog tawm los, lees paub qhov kev ntseeg siab ntawm cov qauv kev kawm tshuab. (c) Kev sib raug zoo ntawm kev sim ntsuas qhov muaj zog thiab tus naj npawb ntawm cov qauv iterations qhia qhov pom muaj pes tsawg leeg ntawm Fe35Ni29Co21Al12Ta3 complex alloy.
Daim duab 2. (a-d) Chav kub deformation thiab interface yam ntxwv ntawm Fe35Ni29Co21Al12Ta3 complex alloy nrog peb-theem qauv, piv txwv li dislocations tau txiav los ntawm L12 nano theem thiab khaws cia nyob rau hauv tsawg modulus B2 micro theem. Dislocations muaj nyob rau ntawm ob qho tib si L12 / FCC coherent thiab B2 / FCC tsis sib txuas; (e) Atomic sojntsuam soj ntsuam ntawm cov tshuaj muaj pes tsawg leeg thiab faib cov yam ntxwv ntawm complex alloys, raws li zoo raws li lub elemental muaj pes tsawg leeg ntawm multi-principal L12 nano theem thiab B2 micro theem.
Daim duab 3. Evolution ntawm dislocation ceev ntawm txhua theem constituent nyob rau hauv Fe35Ni29Co21Al12Ta3 complex alloy nrog strain (a1-d1) ε=0, (a2-d2) ε=8%, thiab (a3-d3) ε{{14} micron uas tsis muaj uldic. Theem tuaj yeem khaws qhov ceev ntawm qhov tsis sib xws ntau dua li (FCC + L12) matrix.
Daim duab 4. (a-b) Engineering stress-strain and true stress-strain curves of complex alloys with different compositions, (c) Kev sib piv ntawm kev ua hauj lwm hardening kev ua tau zoo ntawm Fe35Ni29Co21Al12Ta3 complex alloy nrog rau lwm yam 2Gpa qib ultra{10}} & P siab zog cov ntaub ntawv (D steel, martensitic steel, nruab nrab siab entropy alloys), thiab (d, e) Kev sib piv ntawm yield zog uniform tensile elongation txuam thiab yield zog muaj zog yas khoom txuam ntawm Fe35Ni29Co21Al12Ta3 complex alloy nrog rau lwm cov ntaub ntawv hlau. Kev sib xyaw ua ke ntawm cov cuab yeej cuab tam ntawm chav tsev kub yog qhov zoo dua rau lwm cov ntaub ntawv hlau qhia.
Cov kev tshawb fawb tshawb pom tau luam tawm hauv online hauv Xwm nyob rau hauv lub npe "Machine kev kawm tsim ntawm ductile FeNiCoAlTa alloys nrog lub zog siab". Yasir Sohail thiab Zhang Chongle, kws kho mob cov tub ntxhais kawm los ntawm Tsev Kawm Ntawv ntawm Cov Khoom Siv Science thiab Engineering ntawm Xi'an Jiaotong University, yog thawj thiab thib ob sau ntawv, raws li. Xibhwb Zhang Jinyu, Marx, thiab Academician Sun Jun yog cov kws sau ntawv ntawm daim ntawv. Xib fwb Liu Gang, Xue Dezhen, Associate Professor Yang Yang, thiab cov tub kawm ntawv kws kho mob Zhang Dongdong, Gao Shaohua, Fan Xiaoxuan, thiab Zhang Hang kuj tau koom tes ua haujlwm. National Key Laboratory of Metal Material Strength ntawm Xi'an Jiaotong University yog tib txoj kev sib txuas lus thiab ua tiav chav rau txoj haujlwm no. Txoj hauj lwm no yog thawj zaug uas cov tub ntxhais kawm txawv teb chaws los ntawm Lub Tsev Kawm Ntawv ntawm Cov Khoom Siv Science ntawm Xi'an Jiaotong University tau luam tawm ib tsab xov xwm xwm txheej ua thawj tus sau. Txoj haujlwm no tau txais nyiaj los ntawm National Natural Science Foundation ntawm Tuam Tshoj, 111 Talent Introduction Base, Shaanxi Provincial Science thiab Technology Innovation Team Project, thiab Central University Basic Research Business Fund. Cov yam ntxwv thiab kev sim ua haujlwm tau txais kev txhawb nqa zoo los ntawm Kev Tshawb Fawb thiab Kev Ntsuas Sib Koom Chaw ntawm Xi'an Jiaotong University, Kev Tshawb Fawb Technology Center ntawm Tsev Kawm Ntawv ntawm Cov Khoom Siv Science, thiab Shanghai Light Source.