Hardness Strengthening Ntawm Laser Cladding Txheej

Hauv kev lag luam ntawm high-end manufacturing, cov khoom nto ntawm qhov chaw ncaj qha cuam tshuam rau kev ua haujlwm thiab kev pabcuam lub neej ntawm cov khoom, thiab hnav cov khoom siv feem ntau ua rau lub sijhawm ntxiv thiab nyiaj txiag poob. Txhawm rau txhim kho qhov kev ua tau zoo ntawm cov khoom siv kho tshuab, qhov kev kho kom zoo dua qub yog siv los txhim kho qhov kev ua tau zoo ntawm qhov chaw thiab kev pab lub neej ntawm cov khoom. Ntxiv rau qhov ncaj qha qhov chaw ntxiv dag zog rau cov khoom siv, txheej txheej feem ntau yog npaj rau ntawm qhov chaw, xws li thermal txau rau saum npoo ntawm cov khoom hauv metallurgy, petrochemical thiab lwm yam kev lag luam los txhim kho lub neej kev pab cuam. Txawm li cas los xij, vim qhov tsis zoo ntawm cov thev naus laus zis thev naus laus zis, nws tsis tuaj yeem txhim kho qhov zoo ntawm cov khoom siv. Tsis tas li ntawd, thaum tshwj xeeb coatings yog npaj los ntawm magnetron sputtering, electroplating thiab tshuaj vapor deposition, muaj feem ntau shortcomings xws li txwv thickness thiab tsis zoo adhesion.

Laser cladding thev naus laus zis yog cov cuab yeej tshiab hlau kho qhov chaw, uas feem ntau yog siv los npaj cov tawv tawv tawv-tiv taus coatings nrog lub zog sib raug zoo thiab ob peb yam tsis xws luag. Raws li cov chip-dawb thiab muaj txiaj ntsig 3D txoj kev siv tshuab, laser cladding tau ua tiav rau kev tsim ntsuab thiab rov ua dua tshiab ntawm qee qhov khoom siv high-end engineering.

Laser cladding yog nyob rau saum npoo ntawm lub substrate yuav tsum coated, nrog txawv kev pub mis, los ntawm laser irradiation rau yaj ib tug nyias txheej ntawm lub substrate nto nyob rau tib lub sij hawm, thiab tom qab sai solidification los tsim ib tug heev tsawg dilution thiab metallurgical bonding nrog lub substrate nto txheej. Lub tshuab yog tus cwj pwm los ntawm lub zog siab ceev, siab deposition efficiency, tsis tshua muaj thermal deformation, ceev ceev txias, tsawg dilution tus nqi thiab siab metallurgical zog.

Nyob rau hauv laser cladding, lub laser beam tsom rau ntawm ib qho chaw me me ntawm qhov chaw ntawm cov khoom, ua rau nws ua kom sov sai, ncav cuag lub melting point ntawm cov khoom los yog kub dua. Thaum qhov kub thiab txias, lub substrate tsim ib lub pas dej ua ke nrog cov khoom siv cladding, thiab cov atoms thiab molecules ntawm cov khoom pib ua dynamic nyob rau hauv lub melt pas dej ua ke thiab yuav tsum rearranged mus rau hauv sib txawv siv lead ua qauv los yog tshuaj compositions. Thaum lub laser beam txav mus rau qhov chaw tom ntej, qhov chaw yav tas los melted txias sai heev, tsim ib lub koom haum tshiab, yog li nws yog tsim nyog rau nce hardness ntawm cov khoom.

Lub tshuab uas laser cladding tshuab tuaj yeem txhim kho hardness ntawm cov ntaub ntawv suav nrog cov hauv qab no.

1. Cov nplej ua kom zoo

Vim tias cov txheej txheem laser cladding yog cov txheej txheem tshwj xeeb thiab cov khoom siv tshuaj lom neeg, nws muaj qhov siab melting thiab solidification npaum li cas, uas inhibits kev loj hlob ntawm cov nplej, txhawb kev ua kom zoo ntawm cov nplej, thiab yog li txhim kho lub hardness ntawm txheej. NbMoTaWTi siab entropy alloy txheej tau npaj rau saum npoo ntawm TC4 alloy los ntawm laser cladding, thiab microhardness tau pom tias yog 71.4% siab dua li ntawm cov substrate. Yog vim li cas yog tias cov yaj sai sai thiab txias hauv cov txheej txheem laser cladding ua rau cov nplej tsis tuaj yeem loj hlob sai, yog li cov nplej tau ua kom zoo dua qub, thiab cov tawv tawv tau zoo tuaj.

2. Lattice distortion

Lub distortion ntawm crystal lattice nce hardness ntawm cov khoom. Nyob rau hauv cov txheej txheem ntawm cov yas deformation ntawm laser cladding txheej, ib tug loj tus naj npawb ntawm lattice defects, xws li dislocation thiab vacancy, yuav raug qhia kom ua ib co ntsiab ntawm lub equilibrium lub xeev thiab ua rau lattice distortion. Tom qab lattice distortion, nws feem ntau ua rau muaj zog ntawm cov khoom, ua rau muaj zog microstress ntau dua, inhibiting dislocation plam, thiab txhim kho lub zog thiab hardness ntawm cov khoom. Vim tias lub siab entropy alloy yog tsim los ntawm ntau lub ntsiab lus, qhov loj, qauv thiab kev sib txuas lub zog ntawm txhua lub hauv paus atom yog qhov sib txawv, uas cov atomic loj, daim ntawv cog lus thiab lattice muaj peev xwm lub zog ntawm cov khoom sib txawv tuaj yeem muab faib rau ntawm cov lattice. cov ntsiab lus, ua rau loj lattice distortion ntawm cov qauv siv lead ua, yog li qhov tshwm sim no pom tseeb dua nyob rau hauv high entropy alloy.

3. Theem transformation

Kev hloov ntawm txheej txheej ua rau lub hardness ntawm txheej nce. Laser cladding yog ib tug high-temperature processing technology uas yuav ua kom sov lub nto ntawm cov khoom mus rau qhov kub thiab txias nyob rau hauv ib tug luv luv lub sij hawm, yaj nws ib nrab los yog tag nrho, thiab tsim cov txheej txheem sib txawv los ntawm ceev ceev. Thaum qhov kub thiab txias no, cov atoms thiab cov molecules ntawm cov khoom ua kom muaj zog thiab tuaj yeem hloov mus rau hauv cov qauv siv lead ua kom zoo dua qub, ua rau lub sijhawm hloov pauv ntawm cov khoom siv. CoCrNiMnTix siab entropy alloy laser cladding txheej tau npaj rau ntawm Q235 steel nto. Nws tau pom tias nrog qhov nce ntawm Ti cov ntsiab lus hauv txheej txheej, txheej txheej txheej hloov los ntawm FCC theem mus rau FCC + Laves theem.

Hom thiab kev faib ua feem ntawm cov hmoov yog cov yam tseem ceeb uas cuam tshuam rau kev ua haujlwm ntawm cov txheej txheem. Yog li ntawd, hauv kev sim, nws yog ib qho tseem ceeb heev los tsim cov qauv ntawm cladding hmoov tsim nyog. Tsis tas li ntawd, vim hais tias txoj kev txhim kho ntawm cov txheej txheej yog ze rau nws cov kev txhawb zog, nws yog ib qho tseem ceeb heev uas yuav tsum tau tsim cov hmoov raws li kev txhim kho. Ntawm lawv, theem thib ob ntxiv dag zog, zoo siv lead ua ntxiv dag zog, kev daws teeb meem ntxiv dag zog, microstructure optimization, amorphous thiab microstructure optimization yog txoj hauv kev zoo los txhim kho hardness thiab hnav tsis kam ntawm txheej. Cov teebmeem ntawm cov khoom siv ntxiv rau ntawm cov khoom ntawm cov khoom siv cladding yog qhia hauv Table 1.

Vim hais tias lub hardness ntawm cov khoom qhia txog lub peev xwm ntawm cov khoom los tiv thaiv cov khoom nias rau hauv qhov chaw, qhov siab dua qhov hardness, qhov ntiav qhov tob ntawm cov khoom nias rau saum npoo ntawm cov khoom, qhov me me ntawm cov khoom tawg los ntawm kev txiav, uas yog, qhov me dua hnav, siab dua hnav tsis kam. Yog li ntawd, hardness yuav siv tau los ntsuas qhov hnav tsis kam ntawm cov ntaub ntawv hlau, thiab thaum lub hardness nce, nws hnav kuj yuav nce.