Rau Titanium rhaub nyob rau hauv ib tug boiling tov nrog High Chloride Concentration, Dab tsi yog qhov txawv tseem ceeb nyob rau hauv Corrosion Cwj Pwm ntawm lub hauv paus hlau thiab lub Weld tshav kub-Tshiab cuam tshuam?
Tso lus
Lub vuam cua sov- thaj tsam cuam tshuam (HAZ) ntawm lub tshuab cua sov titanium corrode heev txawv ntawm cov hlau hauv paus hauv kub kub - cov tshuaj chloride (xws li 25% NaCl ntawm 108℃). HAZ muaj ib coarser grain qauv, muaj zog residual kev nyuaj siab thiab muaj peev xwm oxygen contamination (alpha- rooj). Cov khoom no ua rau HAZ ntau dua rau pitting thiab crevice corrosion dua li lub hauv paus hlau. Qhov kev sib txawv tseem ceeb no yog qhov tseem ceeb rau kev tsim vuam thiab kev tshuaj xyuas qhov tseem ceeb.
Quantitative Comparison ntawm Base Hlau vs HAZ
Boiling 25% NaCl ntawm 108 ° C rau 500 teev:
Base hlau (Qib 2) 5-20 pits / cm2 pitting ceev. Qhov siab tshaj plaws qhov tob ntawm 20-50 μm. Corrosion tus nqi 0.02-0.05 hli / xyoo.
HAZ (raws li -welded, tsis muaj ncej- kho): pitting ceev 50–150 pits/cm². Qhov tob txog li 100 txog 300 µm. Corrosion npaum li cas 0.15 txog 0.40 hli ib xyoo. Localized nres ntawm weld ntiv taw.
HAZ (post-weld pickling) Pitting ceev 20-60 pits/cm² Qhov tob 40-100 µm Zoo dua, tab sis tseem tsis zoo li cov hlau puag.
HAZ (Stress alleviated + Pickled) Pitting ceev 10-30 pits / cm² Qhov tob 30-70 µm Ntau dua li cov hlau puag.
Kev cuam tshuam ntawm kev kho tom qab vuam ntawm HAZ tus cwj pwm
Ncej -Kev kho Weld HAZ Qhov ntom ntom (pits/cm²) HAZ Max Qhov tob (µm) Txhim Kho Qhov Ntsuas vs. As-Welded
Tsis muaj (raws li -welded) 50-150 100-300 1x
Pickling xwb 2-3x 20-60 40-100
Kev ntxhov siab tsuas yog 30–80 60–120 1.5–2x
Pickling thiab txo kev ntxhov siab 10–30 30–70 3–5 ×
Electropolishing 5–15 20–50 5–10 × Kev pom zoo Engineering
Pickling (HNO3/HF) thiab post-weld stress relief (540℃, 30 min) yog pom zoo rau welded titanium heaters siv nyob rau hauv siab -chloride boiling kev pab cuam los kho HAZ corrosion kuj mus ze rau hauv paus hlau theem. Hauv kev tshuaj xyuas, muab kev saib xyuas tshwj xeeb rau thaj tsam HAZ, vim qhov no yog qhov chaw pitting thiab crevice corrosion ntau dua. Tus kws tshaj lij paub qhov sib txawv tseem ceeb ntawm lub hauv paus hlau thiab HAZ thiab yog li ntawd tsom mus rau qhov chaw soj ntsuam thiab tom qab- kho.
