بهبود خواص سطح چدن خاکستری از طریق آلیاژسازی درجا

نویسندگان

1 1. دانشکده مهندسی مواد، دانشگاه صنعتی اصفهان

2 2. دانشکده مهندسی مکانیک، دانشگاه صنعتی اصفهان

چکیده

برخلاف روش‌های متداول افزودن عنصر آلیاژی به کل قطعه، در این پژوهش بهبود خواص سطحی چدن خاکستری با استفاده از روش آلیاژسازی درجای سطحی در حین ریخته‌گری بررسی شد. به این منظور سیم‌های مسی به قطر 4/0 و 8/0 میلی‌متر قبل از ذوب‌ریزی در قالب نصب شد. آنالیز عنصری، حضور مس در سطح و لایه‌های زیر سطح تا عمق یک سانتی‌متر را نشان داد. بررسی‌های ریزساختاری تغییر توزیع گرافیت از A به D و E، کاهش فازگرافیت و افزایش پرلیت در سطح را نشان دادند. نتایج سختی سنجی نشان داد که سختی سطح نمونه‌های حاوی مس افزایش یافت و نتایج آزمون سایش مشخص کرد که مقاومت سایشی نمونه با مس نسبت به نمونه شاهد افزایش یافته است.
 

کلیدواژه‌ها


عنوان مقاله [English]

Improving the Surface Properties of Gray Cast Iron through In-Situ Alloying

نویسندگان [English]

  • M. Khoobroo 1
  • A. Maleki 2
  • B. Niroumand 1
1 1. Department of Materials Engineering, Isfahan University of Technology, Isfahan, Iran.
2 2. Department of Mechanical Engineering, Isfahan University of Technology, Isfahan, Iran.
چکیده [English]

Conventionally, alloying elements are being added to the whole melt; however, in this research in-situ surface alloying of gray cast iron was employed to improve surface properties of the castings. Wires of pure copper with diameters of 0.4 and 0.8 mm were inserted and fixed at bottom of sand molds before melting. Chemical composition analysis revealed the presence of copper from surface to a depth of 1 cm. Microstructural investigations indicated that graphite type changed from A to D and E. Moreover, the content of graphite phase decreased while that of pearlite increased at the surface. Hardness was higher at surface of copper added samples. Wear resistant of the in-situ surface alloyed samples was better than the no-copper added ones.
 

کلیدواژه‌ها [English]

  • In-situ alloying
  • Surface alloying
  • Gray cast iron
  • microstructure
  • Hardness
  • Wear resistant
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