نوع مقاله : مقاله پژوهشی

نویسندگان

1 استادیار، دانشکده مهندسی مواد، دانشگاه صنعتی سهند، تبریز

2 دانشجوی کارشناسی ارشد، دانشکده مهندسی و علم مواد، دانشگاه علم و صنعت ایران، تهران.

3 استاد، دانشکده مهندسی و علم مواد، دانشگاه علم و صنعت ایران، تهران

10.22068/jstc.2020.111670.1571

چکیده

اصطکاک و سایش در اغلب کاربردهای مهندسی امری نامطلوب است، اما در کامپوزیت لنت ترمز، اگر چه سایش امری اجتناب ناپذیر است اصطکاک امری لازم است و دستیابی به یک ضریب اصطکاک مناسب و پایدار دغدغه بسیاری از مهندسین این حوزه می‌باشد. در این پژوهش با بررسی سطح سایش لنت ترمز نیمه فلزی، مکانیزم‌های حاکم بر آن مورد بررسی قرار گرفت و تاثیر الیاف فولاد بر تشکیل صفحات تماسی اولیه و ثانویه به عنوان مناطق بلند به وسیله میکروسکوپ الکترونی روبشی (SEM) بررسی گردید. آزمون کنترل کیفی لنت ترمز به منظور آشکار سازی سطوح اصطکاکی و تماسی به وسیله دستگاه اندازه گیری ضریب اصطکاک (Chase Machine) براساس استاندارد SAE J661 انجام گرفت و همچنین مورفولوژی و زبری سطح کامپوزیت اصطکاکی به وسیله رویه نگار اپتیکی سطح بررسی گردید. نتایج نشان می‌دهد که وجود الیاف فلزی به عنوان صفحات تماس اولیه مانند یک سد در مقابل ذرات سایشی عمل کرده و در تشکیل صفحات تماسی ثانویه بسیار موثر بوده و همچنین الیاف فلزی نقش مهمی را در تشکیل فیلم اصطکاکی در کنار مواد روانساز و ساینده ایفا می‌کنند.

کلیدواژه‌ها

عنوان مقاله [English]

Effect of Steel Fibers on Wear Mechanism of Semi-Metallic Brake Pad Composite

نویسندگان [English]

  • Reza Tavangar 1
  • Hamid Ansari -Moghadam 2
  • Alireza Khavandi 3

1 Faculty of Materials Engineering, Sahand University of Technology, Tabriz, Iran.

2 Faculty of Materials Science and Engineering, Iran University of Science and Technology, Tehran, Iran.

3 Faculty of Materials Science and Engineering, Iran University of Science and Technology, Tehran, Iran.

چکیده [English]

Friction and wear in most engineering applications are undesirable phenomena, however in friction material composites, though wear is inevitable, friction is indispensable and reaching to a suitable and stable friction coefficient has been a major concern of many engineers. In this research, the surface wear of semi-metallic brake pad has been studied to assess the governing mechanism of friction surface. To get that point, the effect of steel fibers on the formation of primary and secondary contact plateaus as high lands through scanning electron microscopy (SEM) were investigated. In order to detect the friction layer of the composite, friction test was evaluated according to SAE J661 standard test procedure by a chase machine. The white light interferometer (WLI) was employed to reveal the surface roughness of the friction composite after braking. Output results showed that the presence of metal fibers as primary contact plateaus act as an anchor against abrasive particles and dust playing an effective role in forming the secondary plateaus. As such, metal fibers play an important role in the formation of friction film along with abrasive and lubricant materials.

کلیدواژه‌ها [English]

  • Brake pad composite
  • polymer matrix composite
  • friction material
  • friction film
  • steel fiber
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