Keeb kwm ntawm molybdenum hlau

Txawm hais tias molybdenum tau pom nyob rau hauv lub xyoo pua 18th, nws twb tau siv ua ntej nws nrhiav pom, piv txwv li nyob rau hauv lub xyoo pua 14th, thaum molybdenum-muaj steel siv los ua sabers nyob rau hauv Nyiv, thiab nyob rau hauv lub xyoo pua 16th, thaum molybdenite, vim hais tias ntawm nws. Qhov zoo sib xws hauv cov tsos thiab cov khoom siv lead ua, galena thiab graphite, tau siv los ua graphite, thiab tau raug xa mus rau cov neeg European ntawm lub sijhawm ua "molybdenite".

Xyoo 1754, Swedish chemist BengtAnderssonQvist kuaj molybdenite thiab pom tias nws tsis muaj txhuas, yog li nws xav tias molybdenite thiab galena tsis yog tib yam khoom.

Xyoo 1778, Swedish chemist Scherer pom tias nitric acid tsis hnov ​​​​mob nrog graphite, tab sis reacted nrog molybdenite kom tau ib tug dawb hmoov, uas yog boiled nrog ib tug alkaline tov thiab crystallized rau hauv ib tug ntsev. Nws xav tias cov hmoov dawb no yog cov hlau oxide, tov nrog charcoal tom qab muaj zog cua sov, thiab tsis tau cov hlau, tab sis thaum nws tau rhuab nrog sulfur ua ke tab sis tau txais cov qub molybdenite, yog li nws xav tias molybdenite yuav tsum yog ib hom tsis paub. lub ntsiab ntawm cov mineral.

Raws li Scherer qhov kev tshoov siab, xyoo 1781, Swede Jelm tau siv "txoj kev txo cov pa roj carbon" los cais cov hlau tshiab los ntawm cov hmoov dawb no, thiab hu ua cov hlau "Molybdenum".

Cov hlau nplaum

Molybdenum feem ntau yog siv nyob rau hauv cov hlau thiab hlau, qhov uas nws yog tsuas yog siv nyob rau hauv zus tau tej cov hlau alloys (kwv yees li 43% ntawm tag nrho cov molybdenum noj nyob rau hauv hlau thiab hlau), stainless hlau (kwv yees li 23%), cuab yeej thiab high- ceev steels (kwv yees li 8%), thiab cam khwb cia hlau thiab yob (kwv yees li 6%). Feem ntau ntawm cov molybdenum yog siv ncaj qha rau hauv steelmaking los yog cam khwb cia hlau tom qab briquetted li industrial molybdenum oxide, thaum ib tug me me feem yog thawj smelted rau hauv ferromolybdenum thiab ces siv nyob rau hauv steelmaking. Molybdenum raws li cov khoom siv alloying hauv cov hlau muaj qhov zoo hauv qab no: nws ua kom lub zog thiab tawv ntawm cov hlau; nws txhim kho corrosion kuj ntawm cov hlau hauv cov kua qaub thiab alkaline daws thiab kua hlau; nws nce qhov hnav tsis kam ntawm cov hlau; thiab nws txhim kho cov hardenability, weldability, thiab kub tsis kam ntawm steel. Piv txwv li, stainless hlau uas muaj 4-5 ib xees molybdenum feem ntau siv nyob rau hauv qhov chaw uas yaig thiab corrosion hnyav dua, xws li cov khoom siv marine thiab cov khoom siv tshuaj.

Txhawm rau molybdenum ua lub substrate los ntawm kev ntxiv lwm cov ntsiab lus (xws li titanium, zirconium, hafnium, tungsten thiab lub ntiaj teb tsis tshua muaj cov ntsiab lus, thiab lwm yam) tsim cov hlau tsis muaj hlau, cov alloying ntsiab lus tsis tsuas yog molybdenum alloys ua lub luag haujlwm ntawm cov tshuaj tiv thaiv kom muaj zog thiab tswj xyuas qis. -temperature plasticity, tab sis kuj tsim kom ruaj khov, diffuse faib ntawm carbide theem, txhim kho lub zog ntawm alloy thiab recrystallisation kub. Molybdenum-raws li alloys yog siv nyob rau hauv high cua kub ntsiab, extrusion sib tsoo cov cuab yeej, iav melting rauv electrodes, tshuaj tsuag txheej, metalworking cov cuab yeej, spacecraft qhov chaw thiab lwm yam vim hais tias ntawm lawv zoo zog, mechanical stability thiab siab ductility.