Kev kho cua sov yuav tsum tau ua kom muaj zog bolts

High-strength bolts yog cov khoom tseem ceeb hauv ntau yam kev siv engineering, suav nrog kev tsim kho, tsheb, thiab kev lag luam aerospace. Lawv qhov kev ua tau zoo yog nyob ntawm cov txheej txheem kho cua sov, uas txhim kho lawv cov khoom siv dag zog, xws li lub zog tensile, hardness, thiab qaug zog tsis kam. Kev kho cua sov ntawm lub zog siab bolts feem ntau suav nrog peb theem tseem ceeb: quenching, tempering, thiab kev ntxhov siab.

Quenching yog thawj kauj ruam hauv kev kho cua sov. Covhex boltsyog rhuab mus rau qhov kub siab tshaj lawv qhov kev hloov pauv tseem ceeb, feem ntau ntawm 850 ° C thiab 950 ° C, nyob ntawm cov khoom muaj pes tsawg leeg. Qhov ntsuas kub no tau khaws cia rau lub sijhawm txaus kom ntseeg tau tias cov qauv austenitic tsis sib xws thoob plaws hauv lub bolt. Tom qab cua sov, cov bolts tau txias sai, feem ntau hauv cov roj lossis dej, hloov cov austenite mus rau hauv martensite, ib qho nyuaj thiab nkig microstructure. Qhov txias txias no yog qhov tseem ceeb rau kev ua tiav siab hardness thiab lub zog.

Tempering ua raws li quenching kom txo cov brittleness thiab txhim kho lub toughness ntawm bolts. Cov bolts tau rov ua dua rau qhov kub ntawm 400 ° C thiab 600 ° C, uas tso cai rau lub martensite hloov mus rau hauv cov qauv ntau dua hu ua tempered martensite. Lub tempering kub thiab ntev yog ua tib zoo tswj kom ua tiav qhov xav tau sib npaug ntawm lub zog thiab toughness. Over-tempering tuaj yeem ua rau poob ntawm lub zog, thaum qis-tempering yuav ua rau tsis txaus toughness.

Kev Tiv Thaiv Kev Nyuaj Siab yog kauj ruam kawg hauv kev kho cua sov. Tom qab quenching thiab tempering, residual stresses tseem yuav muaj nyob rau hauv lub bolts vim lub ceev ceev txias thiab theem transformations. Kev ntxhov siab cuam tshuam nrog cua sov lub bolts rau qhov kub hauv qab qhov kub thiab txias, feem ntau nyob ib ncig ntawm 200 ° C txog 300 ° C, thiab tuav lawv ntawm qhov kub no rau ib lub sijhawm tshwj xeeb. Cov txheej txheem no yuav pab txo qis cov kev ntxhov siab sab hauv, txhim kho qhov kev ruaj ntseg thiab qaug zog ntawm lub cevbolts.

Ntxiv nrog rau cov theem pib no, cov txheej txheem kev kho cua sov rau cov bolts muaj zog yuav tsum xav txog yam xws li cov khoom muaj pes tsawg leeg, qhov loj me, thiab daim ntawv thov. Piv txwv li, cov ntsiab lus alloying xws li chromium, molybdenum, thiab vanadium tuaj yeem txhim kho lub hardenability thiab tempering tsis kam ntawm bolts, tso cai rau kev tswj kom meej dua lawv cov khoom siv kho tshuab.

Hauv kev xaus, kev kho cua sov ntawm cov bolts muaj zog yog cov txheej txheem nyuaj thiab tseem ceeb uas cuam tshuam rau lawv qhov kev ua tau zoo. Kev ua kom zoo quenching, tempering, thiab kev ntxhov siab txo kom ntseeg tau tias cov bolts ua tau raws li cov kev cai nruj ntawmsiab zogkev siv, muab kev txhim khu kev qha thiab ruaj khov hauv kev xav tau ib puag ncig.