Cov khoom ntawm tungsten
Atomic naj npawb | 74 |
CAS nr | 7440-33-7 : kuv |
Atomic loj | 183.84 ib |
Melting point | 3420 ° C |
Boiling point | 5900 ° C |
Atomic ntim | 0 ,0159nm3 |
Qhov ceev ntawm 20 ° C | 19.30 g/m² |
Crystal qauv | lub cev-center cubic |
Lattice tas li | 0.3165 [nm] |
Kev nplua nuj nyob rau hauv lub ntiaj teb crust | 1.25 [g / t] |
Ceev lub suab | 4620m / s (ntawm rt) (thin rod) |
Thermal expansion | 4.5 µm / (m·K) (ntawm 25 ° C) |
Thermal conductivity | 173 W / (m·K) |
Hluav taws xob resistivity | 52.8 nΩ·m (ntawm 20 ° C) |
Mohs hardness | 7.5 |
Vickers hardness | 3430-4600 Mpa |
Brinell hardness | 2000-4000Mpa |
tungsten, los yog wolfram, yog ib yam tshuaj muaj cim W thiab atomic tooj 74. Lub npe tungsten los ntawm lub qub Swedish lub npe rau tungstate ntxhia scheelite, tung sten los yog "hnyav pob zeb". Tungsten yog cov hlau tsis tshua muaj nyob hauv lub ntiaj teb yuav luag tshwj xeeb ua ke nrog lwm cov ntsiab lus hauv cov tshuaj lom neeg tsis yog ib leeg. Nws tau raug txheeb xyuas tias yog lub hauv paus tshiab hauv xyoo 1781 thiab thawj zaug cais raws li cov hlau hauv xyoo 1783. Nws yog cov ore tseem ceeb xws li wolframite thiab scheelite.
Cov khoom pub dawb yog qhov zoo tshaj plaws rau nws qhov muaj zog, tshwj xeeb tshaj yog qhov tseeb tias nws muaj qhov siab tshaj plaws melting point ntawm tag nrho cov ntsiab lus pom, melting ntawm 3422 ° C (6192 ° F, 3695 K). Nws kuj muaj qhov kub siab tshaj plaws, ntawm 5930 ° C (10706 ° F, 6203 K). Nws qhov ceev yog 19.3 npaug ntawm cov dej, piv rau cov uranium thiab kub, thiab ntau dua (kwv yees li 1.7 npaug) dua li cov hlau lead. Polycrystalline tungsten yog ib qho khoom siv tawv thiab tawv (raws li tus qauv, thaum tsis sib xyaw), ua rau nws nyuaj rau kev ua haujlwm. Txawm li cas los xij, cov ntshiab ib leeg-crystalline tungsten yog cov ductile ntau dua thiab tuaj yeem txiav nrog lub zog-hlau hacksaw.
Tungsten cov alloys muaj ntau daim ntawv thov, suav nrog cov teeb pom kev zoo ntawm lub teeb ci, X-ray raj (raws li ob qho tib si filament thiab lub hom phiaj), electrodes hauv roj tungsten arc vuam, superalloys, thiab hluav taws xob tiv thaiv. Tungsten lub hardness thiab siab ceev muab nws cov tub rog siv nyob rau hauv penetrating projectiles. tungsten tebchaw kuj tseem siv tau los ua kev lag luam catalysts.
Tungsten yog tib yam hlau los ntawm qhov kev hloov pauv thib peb uas paub tias tshwm sim hauv biomolecules uas muaj nyob rau hauv ob peb hom kab mob thiab archaea. Nws yog qhov hnyav tshaj plaws uas paub tias yog qhov tseem ceeb rau txhua yam kabmob muaj sia. Txawm li cas los xij, tungsten cuam tshuam nrog molybdenum thiab tooj liab metabolism thiab yog me ntsis lom rau cov ntaub ntawv paub ntau dua ntawm cov tsiaj txhu.