ریزساختار و خواص مکانیکی یک فولاد پر کربن کم آلیاژ فراوری شده توسط فرایند کوئنچ و پارتیشن بندی

نوع مقاله : علمی و پژوهشی

نویسندگان

1 دانشگاه سمنان

2 سمنان

چکیده

فرایند سرمایش سریع و بخش‎بندی (Q&P) ، یک عملیّات حرارتی جدید برای تولید نسل سوّم از فولادهای پیشرفته‎ی استحکام بالا و بر اساس نفوذ کربن از فاز مارتنزیت به فاز آستنیت باقی‎مانده است. به‎کارگیری این فرایند برای فولادهای مختلف، منجر به ایجاد ترکیب جالب توجهی از خواص مکانیکی شامل استحکام بالا همراه با انعطاف‎پذیری خوب می‎شود. استفاده از این فرایند در صنعت خودرو باعث عمل‎کرد مکانیکی بهتر، امنیت بالاتر و کاهش وزن و هزینه‎های تولید می‎شود. در این تحقیق، یک فولاد پرکربن کم آلیاژ با این فرایند عملیّات حرارتی شد و ریزساختار و خواص مکانیکی آن بررسی شد. نتایج نشان دادند که ریزساختار فولاد سریع سرد و بخش‎بندی شده، شامل آستنیت پایدار شده‎ی غنی از کربن و مارتنزیت تخلیه شده از کربن است که با هم باعث افزایش استحکام فولاد به‎ازای انعطاف‎پذیری قابل‎قبول می‎شود. انجام فرایند سرمایش سریع و بخش‎بندی، باعث افزایش کسر فاز آستنیت باقی‎مانده و افزایش سختی فولاد شد. فرایند شکست در نمونه‎ی تولیدی به این روش، از نوع شکست ترد و سطح شکست به‎شکل شبه‎کلیواژ بود.

کلیدواژه‌ها

عنوان مقاله [English]

Microstructure and Mechanical Properties of a Low Alloy High Carbon Steel Processed by Quenching and Partitioning Process

نویسندگان [English]

  • Abdollah Shirali 1
  • Abbas Honarbakhsh Raouf 2
  • Soheila Bazzaz Bonabi 1
1 Semnan University
2 Semnan University
چکیده [English]

The quenching and partitioning (Q&P) process is a new heat treatment cycle to produce the third generation of advanced high strength steels based on diffusion of carbon from martensite to retained austenite phase. The application of this process for various steels leads to a remarkable combination of mechanical properties including high strength and good ductility. Using this process in automotive industry causes better mechanical performance, greater car safety, weight saving and cost reduction. In this study, a low alloy high carbon steel has been subjected to Q&P process and its microstructure and mechanical properties have been investigated. The results showed that the microstructure of the quenched and partitioned steel contains carbon-enriched stabilized austenite and carbon-depleted martensite resulting in increasing the strength of steel with an acceptable ductility. Conducting Q&P heat treatment caused the retained austenite content and the hardness of steel to increase. Fracture in specimens treated by Q&P process was of brittle type and their fracture surface was considered to be quasi-cleavage.

کلیدواژه‌ها [English]

  • quenching
  • Partitioning
  • retained austenite
  • martensite

مراجع

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