بررسی جدایش میکروسکوپی آلیاژهای آلومینیوم- مس بوسیله آنالیز حرارتی و مدل‌سازی عددی

نوع مقاله : علمی و پژوهشی

نویسندگان

1 دانشکده مهندسی، دانشگاه حکیم سبزواری، سبزوار

2 دانشگاه فردوسی مشهد

چکیده

در این تحقیق جدایش میکروسکوپی در آلیاژهای دوتایی آلومینیوم- مس حاوی 2/2، 7/3 و 8/4 درصد وزنی مس با استفاده از آنالیز حرارتی تفاضلی و مدل‌سازی عددی بررسی شد. آلیاژهای مورد نظر با استفاده از یک کوره آنالیز حرارتی تفاضلی با قابلیت کوینچ نمونه‌ها ذوب و با سرعت‌های 008/0 و 083/0 درجه بر ثانیه منجمد و از دماهای معینی در حین انجماد کوینچ شدند. شکل‌گیری ریزساختار و جدایش میکروسکوپی با در نظر گرفتن و بدون در نظر گرفتن تهی‌جاهای اضافی به صورت عددی مدل‌سازی شد و مشخص گردید که در نظر گرفتن تهی‌جاهای اضافی در مدل‌سازی منجر به توافق بهتر نتایج مدل‌سازی با نتایج تجربی می‌شود.

کلیدواژه‌ها


عنوان مقاله [English]

The Study of Micro-segregation in Al-Cu Alloys Using Thermal Analysis and Numerical Modeling

نویسندگان [English]

  • Mohammad Hasan Avazkonandeh Gharavol 1
  • Mohsen Haddad Sbzevar 2
1 Hakim Sabzevari University, Sabzevar, Iran
2 Ferdowsi University of Mashhad, Mashhad, Iran
چکیده [English]

The micro-segregation in binary Al-Cu alloys containing 2.2, 3.7, and 4.8 wt.% copper was investigated by differential thermal analysis (DTA) and numerical modeling. For this purpose, the alloys were melted using a DTA furnace with the capability of quenching samples during solidification. The melted samples were cooled at 0.008 and 0.083 K/s and subsequently quenched from predetermined temperatures during cooling. The evolution of the microstructure and micro-segregation was modeled with and without considering excess vacancies formed during solidification. It was found that the experimental and modeling results show a better correlation when excess vacancies are considered

کلیدواژه‌ها [English]

  • Al-Cu Binary Alloys
  • Micro-Segregation
  • Thermal Analysis
  • Excess Vacancy
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