پیش بینی شکست صفحات گرافیتی دارای شیار کلیدی شکل با استفاده از معیار چگالی انرژی کرنشی مبتنی بر مفهوم ضریب معادل

نوع مقاله: مقاله مستقل

نویسندگان

1 دانشیار، مهندسی مکانیک، دانشگاه تهران، تهران

2 کارشناس ارشد، مهندسی مکانیک، دانشگاه علم وصنعت ایران، تهران

3 استاد، مهندسی مکانیک، دانشگاه علم وصنعت ایران، تهران

چکیده

در این پژوهش، معیار چگالی انرژی کرنشی به منظور پیش بینی بار شکست در قطعات مهندسی ضعیف شده با شیار کلیدی‌شکل تحت بارگذاری مود ترکیبی کششی برشی اصلاح شده است. این معیار جدید بر اساس مفهوم ضریب مود یک معادل می‌باشد که در قالب یک حل دقیق جدید‌ ارائه شده است. در واقع روش جدید ارائه شده بر پایه‌ی مفهوم مود یک محلی معادل می‌باشد که پیشتر بر روی شیارهای U و Vشکل، اعمال شده است اما در این پژوهش ضریب معادل جدید به منظور کاهش حجم محاسبات معرفی شده است. بنابراین با اعمال ضریب مود یک معادل می‌توان از بخش بزرگی از محاسبات قسمت انرژی حالات بارگذاری مود ترکیبی جهت پیش‌بینی بار شکست نمونه‌های شیاردار صرف‌نظر کرد. به منظور اعتبارسنجی روش جدید ارائه شده، مقادیر پیش‌بینی‌های تئوری با تعداد زیادی از داده‌های تجربی گزارش‌شده در مقالات که از آزمایش شکست نمونه‌های گرافیتی دارای شیار کلیدی‌شکل به‌دست آمده بودند، مقایسه شدند. در نهایت، نشان داده شده است که مدل ارائه شده جدید با اختلاف کل حدود 6 %، معیار شکست مناسبی می-باشد.

کلیدواژه‌ها

موضوعات


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