Lub cev thiab tshuaj thaj chaw ntawm cov hlau

Paub qhov txawv hauj, lub cev, neeg kho tshuab thiab tshuaj thaj chaw ntawm hlau. Lub cev attribute kev nqus, xim, hluav taws xob conductivity. Tus yam ntxwv ntawm no pab pawg neeg kuj thermal conductivity, melting tus cwj pwm thiab kev ceev ntawm cov hlau.

Los ntawm cov neeg kho tshuab cov yam ntxwv xws li yooj, elasticity, hardness, muaj zog, toughness.

Tshuaj thaj chaw ntawm hlau muaj xws li xeb kuj, solubility thiab oxidation.

Cov yam ntxwv xws li "castability", hardenability, weldability, ductility, yog hauj.

lub zog

1. Xim. Co tsis dhau lub teeb los ntawm nws, hais tias yog tsis tshab. Nyob rau hauv reflected teeb, txhua lub caij nws muaj nws tus kheej ntxoov ntxoo - xim. Ntawm cov kev coloring hlau muaj tsuas tooj liab thiab alloys nrog nws. Rau lwm yam hais cov yam ntxwv yog cov Hawj txawm ntawm cov nyiaj-dawb rau grey-hlau.
2. Fusibility. Qhov no characterization qhia lub peev xwm ntawm lub caij nyob rau hauv tshav kub los ua kua los ntawm khoom. Fusibility yog suav tias yog lub feem ntau tseem ceeb thaj chaw ntawm hlau. Thaum lub sij hawm cov cua kub, tag nrho cov co los ntawm khoom ua kua. Thaum cua txias, lub molten yeeb tshuaj, qhov rov qab hloov - los ntawm cov kua rau khoom hauv lub xeev.
3. Hluav taws xob cov conductivity. Qhov no yam ntxwv qhia cov muaj peev xwm mus hloov cov dawb electrons ntawm hluav taws xob. Cov hluav taws xob conductivity ntawm cov hlau lub cev yog ib txhiab lub sij hawm ntau tshaj uas tsis yog-nws yog xim hlau. Nrog ib qho kev nce nyob rau hauv kev tivthaiv kub hluav taws xob conductivity decreases, thiab raws li qhov kub thiab txias txo, feem tsub kom. Nws yuav tsum tau muab sau tseg tias conductivity ntawm lub alloys yeej yuav qis dua tej hlau constituting lub alloy.
4. Sib Nqus zog. Yuav kom meej meej magnetic (ferromagnetic) hais, xws li xwb cobalt, npib tsib xee, hlau thiab ib tug xov tooj ntawm alloys thereof. Txawm li cas los, thaum lub sij hawm cov cua kub mus rau ib tug kev cai tswjhwm kub hais tias tshuaj tsis tau lawv lub magnetism. Xaiv hlau alloys ntawm chav tsev kub yog tsis yog ferromagnetic.
5. Thermal conductivity. Qhov no characterization qhia lub tshav kub muaj peev xwm rau txoj kev hloov los ntawm ib tug tsawg rhuab lub cev rhuab tsis khees xaav ntawm nws constituent hais. Cov theem siab ntawm thermal conductivity tso cai thaum tshav kub kub thiab txias hlau tusyees thiab sai sai. Ntawm cov kev hais muaj lub siab tshaj plaws nqi ntawm tooj liab.

Co nyob rau hauv Science News for KIDS nyob ib tug tshwj xeeb qhov chaw. Lub xub ntiag ntawm lub coj yam ntxwv tso cai rau kom siv ib yam khoom uas nyob rau hauv ib tug tej yam cheeb tsam.

Tshuaj thaj chaw ntawm cov hlau

1. Corrosion. Corrosion hu ua kev puas tsuaj rau cov ntaub ntawv uas los ntawm electrochemical los yog tshuaj sib raug zoo nrog cov ib puag ncig. Feem ntau cov piv txwv yog suav tias yog rusting hlau. Corrosion kuj ntawm cov tseem ceeb tshaj plaws tej yam ntuj tso cov yam ntxwv ntawm ib tug xov tooj ntawm cov hlau. Nyob rau hauv no hais txog, cov ntaub ntawv xws li nyiaj, kub, platinum, yog hu ua cov noble. Nws muaj xeb kuj npib tsib xee thiab lwm yam nonferrous hlau. Ferrous co yog cov yuav raug kev puas tsuaj sai thiab muaj zog tshaj cov xim.
2. Oxidizability. Qhov no yam ntxwv qhia ib lub caij tus muaj peev xwm yuav hnov mob nrog O2 nyob rau hauv tus ntawm oxidizing agents.
3. Solubility. Co muaj ib cov kua unlimited solubility thaum hardening yuav tsim khoom daws teeb meem. Nyob rau hauv cov ntsiab lub atoms ntawm ib feem kos nyob rau hauv lub siv lead ua ntxaij ntoo ntawm lwm cov povntawv xwb tsis pub dhau tej yam kev txwv.

Nws yuav tsum tau muab sau tseg tias lub cev thiab tshuaj thaj chaw ntawm cov hlau yog ib co ntawm cov ntsiab yam ntxwv ntawm cov ntsiab.