Quid est Duplex Steel seamless pipe formans processus solvere quaestionem calor exchanger corrosio?

In agro de calor deoccupit, traditional welded duplex ferro fistularum longum turbata a intergranular corrosio per calorem affectus zone (HAD). Et essentia huius phaenomenon est quod loci summus temperatus (1000-1350 ℃) per Welding causat diffusio de carbon et NITROGENIUM ELEMENTUM in DUPLEX STENITEDE, formatam et NITROGENDUS EXPLEX (CRENTENITE ad FERRITUS tempus, quod fit in Breakthrough in Ferrite Medium. Et Duplex Steel calor exchanger seamless pipe excludit hoc occultatum periculum ex fons materialis formatam per innovation calidum extrusionem et centrifuga mittentes processibus, providente novum paradigma pro diu-term operationem apparatu sub mordendo conditionibus.

Et core de vestibulum Duplex Steel seamless Pipes mendacium in precise imperium temperatus et accentus agri. In calidum extrusionem processum, in Billet transit per peculiari mori (deformationis rate 0.1-10mm / s) in range de 850-1150 ℃ et formas uniformis (in actione dynamic (DRX). Per hoc processus, quod internus peccetur densitas in materia est quod altum quod 10¹² / M², quae providet a driving vim pro migratione in Austenite / Ferrite Ratio ad XLV: LV III%. Comparari cum welding processus, ibi est locus overheating zonam in calidum extrusionem processus et diffusio coefficientem chromium reducitur duo ordines magnitudinis.

Centrifugal casting technology realizes directional solidificatione fusilia metallum per centrifuga vi agri (100-200g). In mittebat temperatus MCDL ℃, in Dual-tempus ferro conflefaci forms columnar crystal structuram in rotating aeris fingunt (celeritate 800-1200rpm) et primaria Dendrite spacing (pdas), et in 30μm. Et clavem processus parametri includit supercooling imperium (Δt = 15-25K) et fingunt refrigerationem rate (> C ℃ / s), ensuring quod Ferenite phase preferentially in fingere murum et austenate phase praeclaratum uniformiter in finem solidificationem.

Lamellar Dual-Phase structuram (Lamellar spacing 0.5-2μm) formatae in seamless pipe formando processus habet unicum corrosio praesidium mechanism. In Cl⁻-quibus Medium, Austenite (γ Phase) constituit ossa de passivation film ut an electrochemically iners tempus, et Ferrite (α Phase el el elementum preferentially (Δ [α Du el el elementum preferentialiter (Δ [α Duff. XPS Analysis ostendit quod hoc dynamic statera maintains in crassitudine superficiem crito₃ film ad 4-6nm, efficaciter exornatum penetratio de mordendo media.

Per scelerisque exolvuntur, in dual-phase structuram de seamless pipe exhibet optimum tempus transmutatio lenta. Cum temperatus resurget super MS punctum (circiter -40 ℃), pars austenite subit martensitic Phase transformatio (ε → α '), et volumen expands per circiter III%. Hoc reversible tempus transmutatio (ΔV = 0.02) potest absorbet scelerisque accentus et inhibere in initiation labore fragments. Experiments show that after 2000 times of -40℃→350℃ thermal shock, the surface roughness Ra of the seamless pipe only increases by 0.12μm, while the welded pipe has obvious microcracks due to HAZ embrittlement.

Per electrochemical impeditance spectroscopy (Eis) Analysis, Polaration Resistentia (RP) de seamless Pipes in 3.5wt% Nacl solutio pervenit 1.2 × 10⁶ω · cmq, quod est XL% altior quam quod de fistularum. In discrimine pitting temperatus (CPT) test, in seamless pipe manente passiva 4Mol / l Fecl₃ solution ad LXXXV ° C, dum Sweld pipe ostendit firmum pitting ad LXV ° c. Hoc est ex eliminanda sensitization zonam de haz per seamless structuram (latitudo in carbide praecipitatio zonam reducitur ex 20-50μm de fistula ad 0).

In accentus corrosio fregisset (SCB) experimentum, in quattuor-punctum flectendo modum solebat adhibere ad applicare a trensile accentus de LXXX% de cede vires. Post immersionem in ferventis mgcl₂ solution ad 3000H, quod crack incrementum rate of theamless pipe erat da / Dt = V × 10⁻⁻¹m / s, quae duorum ordines magnitudinis inferiori quam de hoc duo ordines. Et microscopic mechanism est quod uniformis dual-phase structuram in seamless pipe auget Hydrogenii captionem density (peccetur, tempus terminus) per III temporibus, efficaciter capture diffusa hydrogenii in III temporibus, effective capturam diffusa Hydrogenii III temporibus, effective capture diffusa hydrogenii atomis.

Current Research Focuses in Nano-Scale tempus terminus Engineering: by Adding Vestigium amounts of NB et TI elementa (0.1-0.3wt%), MC-genus carbides (mole est adhuc augendae ad Dual-captionem. Develop a gradiente structuram seamless pipe (Austenite-dives exteriori murum pro erosion resistentiam, Ferrite-dives interiorem murum ad corrosio resistentia), et consequi componendo gradiente.