1. Cov khoom siv hlau nplaum yog dab tsi?
Cov ntaub ntawv yuav raug magnetized nyob rau hauv qhov kev txiav txim ntawm ib tug sab nraud magnetic teb los tsim tej yam ntxwv magnetic zog. Yog hais tias cov khoom yog magnetized nyob rau hauv qhov kev txiav txim ntawm ib tug sab nraud magnetic teb thiab muaj peev xwm tswj tau tas li muaj zog hlau nplaum nyob rau hauv lub sij hawm ntev thaum lub sab nraud magnetic teb raug tshem tawm, nws yog hu ua ib tug mus tas li hlau nplaum khoom los yog ib tug nyuaj magnetic khoom. Yog tias cov khoom sib nqus hloov pauv raws li cov hlau nplaum hloov pauv, nws yog hu ua mos hlau nplaum. Txhawm rau ua kom tiav, cov khoom sib nqus tuaj yeem muab faib ua cov khoom sib nqus tawv (cov hlau nplaum tas mus li) thiab cov hlau nplaum mos.
2. Cov khoom tseem ceeb ntawm cov khoom siv hlau nplaum ruaj khov
1) Residual hlau nplaum
Tom qab qhov chaw sib nqus sab nraud yog magnetized, qhov sib nqus induction siv tus nqi ntawm cov khoom siv hlau nplaum ruaj khov yog tau thaum cov hlau nplaum sab nraud raug tshem tawm thiab ncav cuag xoom.
2) Coercive zog
Thaum cov khoom siv hlau nplaum ruaj khov yog magnetized rau saturation magnetization thiab rov qab magnetic teb yog siv, qhov rov qab magnetic teb siv yuav tsum tau thaum lub residual magnetization induction siv ntawm cov hlau nplaum ruaj khov cov khoom poob mus rau xoom.
3) Cov khoom siv hluav taws xob sib nqus
Tus nqi siab tshaj plaws ntawm lub zog magnetic teb muab los ntawm cov khoom siv hlau nplaum ruaj khov rau sab nraud magnetic circuit. Nco ntsoov tias qhov loj ntawm cov khoom siv hluav taws xob sib nqus ncaj qha qhia qhov ua tau zoo ntawm cov hlau nplaum. Tus naj npawb ntawm qib NdFeB cov khoom siv hlau nplaum ruaj khov thiab Samarium Cobalt cov khoom siv hlau nplaum ruaj khov yog cov khoom siv hluav taws xob ntau tshaj plaws.
3. Keeb kwm ntawm cov khoom siv hlau nplaum ruaj khov
Peb lub teb chaws cov ntaub ntawv cov ntaub ntawv tuaj yeem txheeb xyuas tau tias Tuam Tshoj muaj keeb kwm ntev ntawm kev siv cov khoom sib nqus mus tas li. Thaum ntxov Lub Caij Nplooj Ntoos Hlav thiab Caij Nplooj Ntoos Hlav thiab Lub Sijhawm Warring States, Sinan ua los ntawm cov khoom siv hlau nplaum ruaj khov (ferric oxide) tau siv rau cov lus qhia los txheeb xyuas cov lus qhia. Tom qab ntawd nws tau tsim los ua ib lub compass. Los ntawm Song Dynasty nws twb siv nyob rau hauv navigation. Tam sim no, tsis muaj cov khoom siv lub cev tau pom nyob rau hauv archaeological excavations, tab sis nws tuaj yeem txheeb xyuas tau tias Tuam Tshoj tau tshawb pom cov khoom ntawm cov khoom siv hlau nplaum ruaj khov thaum ntxov thiab siv lawv hauv kev xyaum ua neej txhua hnub.