بررسی ترمودینامیکی فرایند آلومینیم‌دهی تیتانیم خالص با استفاده از مخلوط پودری

نوع مقاله : علمی و پژوهشی

نویسندگان

1 دانشگاه علم و صنعت ایران

2 دانشگاه پلی‌تکنیک شمال‌غرب چین

چکیده

در این تحقیق، از مخلوط پودری آلومینیم‌دهی حاوی یکی از دو مادهی فعّالکنندهی NaF و NH4Cl برای آلومینیم‌دهی نمونه‌های تیتانیمی خالص استفاده شد. نتایج نشان دادند که بهترتیب لایه‌هایی از جنس TiAl3،TiAl2، γ-TiAl، α2-Ti3Al و محلول جامد آلفا بر روی این نمونه‌ها در هر دو حالت تشکیل می‌شود، امّا میزان افزایش وزن نمونه‌ها و ضخامت لایهی‌ TiAl3 بههنگام استفاده از مادهی فعّالکنندهی NH4Cl بیش‎تر از حالتی بود که از NaF استفاده شد. استفاده از یک مدل ترمودینامیکی نشان داد که فشارهای جزئی گازهای حاوی آلومینیم در حالتی که از NH4Cl استفاده شد، بیشتر بود. بنابراین، نتایج مشاهدات فوقالذکر توجیه شد.

کلیدواژه‌ها

عنوان مقاله [English]

Thermodynamic Investigation of Pack Aluminizing Process of Pure Titanium

نویسندگان [English]

  • Hamid Reza Karimi Zarchi 1
  • Mansour Soltanieh 1
  • Mohammad Reza Aboutalebi 1
  • Xiping Guo 2
1 Iran University of Science and Technology
2 China
چکیده [English]

In this research, aluminizing packs containing NaF and NH4Cl activators were used for aluminizing of pure titanium samples at 1100 ºC. The results showed that the layers of TiAl3, TiAl2, γ-TiAl, α2-Ti3Al, and α-solid solution are formed on titanium samples in both cases. However, the weight gain and the thickness of TiAl3 layer in treated samples with NH4Cl activator are greater than those when NaF activator is used. Using a thermodynamic model showed that the partial pressures of aluminum-containing gases when NH4Cl is used are much greater and accordingly, the experimental results were justified.

کلیدواژه‌ها [English]

  • Titanium aluminide
  • Aluminizing
  • Thermodynamical-chemical model
  • Pack aluminizing reactions

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