Stainless hlau 347

Stainless hlau 347 yog niobium (Nb) - qib austenitic ruaj khov, siv Nb + Ta (10 × C–1.00%) los tsim cov carbides ruaj khov. Cov no ua tau zoo tshaj titanium carbides nyob rau hauv thermal cycling, ua rau nws zoo tagnrho rau nquag tshav kub mus (aircraft cav) thiab nuclear daim ntaub ntawv.

Tshuaj muaj pes tsawg leeg (Key, % ASTM A240): C Tsawg dua lossis sib npaug rau 0.08; Cr17.0–19.0; 9.0–13.0; Nb+Ta10 × C–1.00 (min 0.70); Mn Tsawg dua lossis sib npaug rau 2.0

Mechanical Properties (Annealed): Tensile Strength Ntau dua lossis sib npaug rau 515MPa; Yield zog ntau dua los yog sib npaug rau 205MPa; Elongation Ntau dua lossis sib npaug li 40%; Hardness Tsawg dua los yog sib npaug rau 217HB

Kev Ua Haujlwm ZooNb carbides ruaj khov ntawm 1200℃(Ti ntawm 1000 degree); zoo heev thermal cycling kuj; hluav taws xob- ruaj khov; tsawg weld cracking txaus ntshai.

Daim ntawv thov: Aircraft engines, nuclear siab hlab ntsha, tshuaj reactors.

Qib sib npaugTom ntej: EN1.4550, JIS SUS347, DIN X6CrNiNb18-10Sib piv nrog 321: 347 resists corrosion zoo dua nyob rau hauv thermal voj voog; 321 yog pheej yig dua rau static siab kub.

FAQs

Nb stabilization txawv li Ti hauv 321 li cas? Nb cov ntaub ntawv carbides (NbC) ruaj khov ntawm 1200℃(TiC ntawm 1000 degree), yog li 347 khaws cov corrosion kuj ntawm cov temps siab dua. Nb carbides tiv thaiv kev tawg / re- nag lossis daus hauv cov cua sov, ua 347 zoo dua rau cov cua sov / cua txias (aircraft exhausts). 347 xav tau 10 × C Nb (vs . 321's 5 × C Ti) rau tag nrho cov pa roj carbon binding, txhim khu kev ntseeg tau.

 

Vim li cas 347 siv nyob rau hauv cov hlab ntsha nuclear? Nws tiv thaiv intergranular corrosion nyob rau hauv cov pob qij txha welded (tseem ceeb rau kev tiv thaiv hluav taws xob xau). Austenitic qauv resists hluav taws xob embrittlement (ferritic qib ua nkig). Nb carbides ntxiab hluav taws xob-induced defects, khaws cia ductility. Tsis muaj kev tshaj tawm-weld annealing simplifies loj nkoj fabrication, txo cov kev pheej hmoo ntawm kev puas tsuaj.

 

347 piv rau 304L li cas? 304L (C Tsawg dua los yog sib npaug li 0.03%) tsis muaj kev ruaj khov, corroding nyob rau hauv welded siab -kub apps. 347 resists intergranular corrosion thiab tuav lub zog siab tshaj 600℃. 304L yog pheej yig dua rau tsawg- kev nyuaj siab siv (khoom noj khoom haus); 347 yog qhov tsim nyog rau welded siab - cov khoom cua sov (boiler raj) qhov twg 304L tsis ua haujlwm.

Txoj kev zoo tshaj plaws rau weld 347 yog dab tsi? Siv TIG/MIG nrog 347 muab tub lim (muab Nb cov ntsiab lus). Tsawg cua sov input minimizes HAZ grain loj hlob. Argon shielding (99.99%) tiv thaiv porosity. Tsis xav tau preheating; ncej-weld grind/pickle kom tshem tawm oxide nplai. Zam tsis txhob hla ntau dhau; tsis tu ncua mus txawv tebchaws ceev tiv thaiv kub tawg.

 

347 puas tuaj yeem siv rau hauv cryogenics? Yog, tab sis 321 zoo dua. Ob leeg muaj cov qauv austenitic ruaj khov ntawm -196 degree, tab sis 321's finer Ti carbides boost toughness . 347's loj Nb carbides ua raws li me me kev ntxhov siab concentrators, txo qhov cuam tshuam tsis kam. 347 suits tsis yog - siv cryo tseem ceeb (me LN2 tso tsheb hlau luam); 321 rau cov neeg muaj kev ntxhov siab siab ( foob pob hluav taws roj tso tsheb hlau luam ).