Sut Mae'r Cynnwys Cynhwysion (fel y'i Mesurwyd gan ASTM E45, Math A vs Math C) mewn Tiwb Gwresogydd Titaniwm Gradd 2 yn Cydberthyn â'r Dwysedd Pitting mewn Datrysiad Bromin 0.5% ar 50 gradd?

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) yn arwain at ddwysedd tyllu 5–10 × yn uwch na deunydd glân (graddfa E45<1).

Graddfa Dwysedd Pitting vs Cynhwysiant (Meintiol)

Yn 0.5% Br 2 ar 50 C am 500 awr

Graddfa Cynhwysiant ASTM E45 Ti₂Fe Dwysedd Gronynnau (gronynnau/mm²) Dwysedd Trawiad (pyllau/cm²) Dyfnder Pwll Uchaf (µm)<0.5 (extremely clean) <50 5–20 20–50
0.5-1.0 (glân) 50-150 20-60 40-100
1.0-1.5 (cymedrol) 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
Difrifoldeb Pitting vs Math o Gynhwysiad

Math o Gynhwysiad (ASTM E45)Difrifoldeb Tyllu Titaniwm (cymharol) Nodweddiadol
Math A (sylffidau) Isel Prin iawn
Math B (Aluminate) (1) Isel Prin
Math C (silicadau) Achlysurol Cymedrol
Math D (globular ocsidau/Fe{0}}gyfoethog) Canllaw Rheoli Cynhwysiant Uchel Cyffredin

Dwysedd Tyllu Gofynnol (pyllau/cm2) Graddfa Uchaf ASTM E45 Gweithgynhyrchu a Argymhellir 20 0.5 Toddi VAR (ail-doddi arc gwactod)
20-50 <1.0 Double VAR
50-100 <1.5 Single VAR plus clean feedstock >100 >2.0 Heb ei argymell ar gyfer gwasanaeth B2
Cynnig peirianneg

Gwasanaeth bromin ar 50 gradd: Tiwb titaniwm gyda gradd cynhwysiant ASTM E45<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.