Surface treatment of cast iron by adding different alloying elements to form metallic glass structure layer using an industrial carbon dioxide laser
نام عام مواد
[Thesis]
نام نخستين پديدآور
M. Riahi
نام ساير پديدآوران
M. F. F. Fahmy, John T.
وضعیت نشر و پخش و غیره
نام ناشر، پخش کننده و غيره
University of Northern Iowa
تاریخ نشرو بخش و غیره
1991
مشخصات ظاهری
نام خاص و کميت اثر
141
یادداشتهای مربوط به پایان نامه ها
جزئيات پايان نامه و نوع درجه آن
D.I.T.
کسي که مدرک را اعطا کرده
University of Northern Iowa
امتياز متن
1991
یادداشتهای مربوط به خلاصه یا چکیده
متن يادداشت
Wear and corrosion are the two factors that make utilization of metals very costly. Extraordinary amount of time and money is spent to replace metallic parts affected by either wear or corrosion. Cast iron that is used very widely in a host of different industrial products is one such metal. Among the various methods used to improve the properties of metals, production of amorphous metals is highly noticeable. This process is done by treating the base metal in a certain technique which produces a metal that is more resistant to wear and corrosion. This study was conducted to examine the prospect of forming a metallic glass layer on the surface of gray cast iron by adding boron, silicon and cobalt; coupled with the utilization of an industrial carbon dioxide (CO2) laser. Three different mixing ratios of the aforementioned alloying elements as well as four different groove sizes on the surfaces of the samples were used. Determination of the characteristics of the laser-formed layers on the surfaces of the samples were conducted by the utilization of x-ray diffraction techniques, mechanical testing, Rockwell hardness testing method, as well as metallographic examinations. The collected test results led to the conclusion that the formation of amorphous metal on the surface of gray cast iron is possible and practical when certain percentage of mixing ratios of boron, silicon and cobalt are used and lased by a 1300 watts industrial CO2 laser. Furthermore, the hardness results indicated that a considerably higher degree of hardness resistivity, up to 70 HRC is achievable on the surface of a gray cast iron that has a hardness resistivity of 32 HRC. The micrographical analysis of the formed layers showed textures of a super-saturated structure that presented a high degree of resistivity to both wear as well as corrosion. Boron content attributed to achieving of a high degree of hardness. Particularly when mixed with cobalt and silicon, in the ratio of up to 40% boron content, improved the hardness number directly. Beyond the 40% ratio, the effect of boron on the hardness improvement was not very significant. Three geometrically shaped grooves were machined on the surface of each specimen. Each shape was machined in four different depths on four different specimens. The depth of the lased areas ranged from 0.45mm to 2.15mm.
موضوع (اسم عام یاعبارت اسمی عام)
موضوع مستند نشده
Applied sciences
موضوع مستند نشده
Industrial engineering
موضوع مستند نشده
Mechanics
موضوع مستند نشده
Metallurgy
نام شخص به منزله سر شناسه - (مسئولیت معنوی درجه اول )