Cov ntsiab lus suav nrog li cas (raws li ntsuas los ntawm ASTM E45, Hom A vs. Hom C) hauv qib 2 Titanium rhaub Tube sib cuam tshuam nrog Pitting ntom hauv 0.5% Bromine tshuaj ntawm 50 degree?

In grade 2 titanium, pitting initiation sites are inclusions, especially Ti₂Fe particles. Inclusions are classified by kind according to ASTM E45 as follows: kind A (sulphides, rare in titanium), Type B (aluminates), Type C (silicates), and Type D (globular oxides). In titanium, the most prevalent and most harmful inclusions are iron-rich (Type D). The pitting density in the bromine solutions increases with the increase of the inclusion concentration. A severe inclusion rating (E45 rating >2) ua rau pitting ceev 5-10 × siab dua cov khoom huv si (E45 ntsuam xyuas<1).

Pitting Density vs Inclusion Rating (Quantitative)

Hauv 0.5% Br 2 ntawm 50 C rau 500 teev

ASTM E45 Inclusion Rating Ti₂Fe Particle Density (particles / mm²) Pitting Ceev (pits / cm²) Max Qhov tob (µm)<0.5 (extremely clean) <50 5–20 20–50
0.5-1.0 (huv) 50-150 20-60 40-100
1.0-1.5 (nruab nrab) 150-300 50-150 80-180
1.5-2.0 (mod-heavy) 300-600 100-300 120-250 >2.0 (heavy) >600 200-500 200-400
Severity of Pitting vs. Type of Inclusion

Hom kev suav nrog (ASTM E45) Titanium Pitting Severity (tus txheeb ze) Hom
Hom A (sulphides) Tsawg tsawg heev
Hom B (Aluminate) (1) Tsawg tsawg
Hom C (silicates) Lub Sijhawm Nruab Nrab
Hom D (globular oxides / Fe-nplua nuj) Phau Ntawv Qhia Kev Tswj Xyuas Kev Ruaj Ntseg

Yuav Tsum Tau Pitting Ceev (pits/cm2) Qhov siab tshaj plaws ASTM E45 Kev Ntsuas Pom Zoo Kev Tsim Khoom 20 0.5 VAR melting (lub tshuab nqus tsev arc remelting)
20-50 <1.0 Double VAR
50-100 <1.5 Single VAR plus clean feedstock >100 >2.0 Tsis pom zoo rau kev pabcuam Br2
Tswv yim engineering

Kev pabcuam Bromine ntawm 50 degree: Titanium raj nrog ASTM E45 suav nrog qib<1.0 (clean). Use of double vacuum arc remelted (VAR) material for lowest content of inclusions. The engineer controls the inclusion content to lessen the pitting density in harsh bromine solutions.