International Research Journal of Engineering and Technology (IRJET)
e-ISSN: 2395 -0056
Volume: 04 Issue: 02 | Feb -2017
p-ISSN: 2395-0072
www.irjet.net
Characterization of Casting and Deformation Process of a Metal Alloy Rahul Srinivasa1, Ravigoda Patil1 1Department
of Electrical and Computer Engineering, University of Rajastan
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Abstract - A measure of alloy’s ability to be cast with a
given shape with a given casting process is castability that limited by Fluidity such as surface finish and wall thickness. Good condition of cast products and declines their final quality such as rejection of a shaped casting due to incomplete filling of the mould is influenced by Fluidity. In consequence of the large production volumes included in casting processes decrease in the amount of casting defects can give large economic advantages. Key Words: (Size 10 & Bold) Metal Forming, Castability, Metal thickness
1. INTRODUCTION For both pure and commercial aluminium foundry alloys credible fluidity data are not easily attainable. Fluidity has a substantial impact on alloy final quality specially when alloys are part of the systems operating in very high or low temperatures like low temperature refrigeration systems [1]. These systems provide much lower temperatures compared to conventional refrigeration systems [2], as low as -40° C. In any event, for optimization of mould filling calculations during solidification these data are so significant [-1]. In the foundry the distance that a molten metal can flow in a mould of a constant cross-sectional area before it solidifies is denoted by the term “fluidity” . There are various mathematical models that can demonstrate the behaviour of metal while in fluid state as in [3, 4]. This model can useful in determining the effect of aluminium alloys in the harmonics applied to the power systems transmission which may load the customers financially [5]. This explanation is a principle temperature related property of a liquid, thus it is different from the explanation demonstrated in physics which deduces fluidity as the inverse of viscosity [6, 7, 8]. After the first fluidity test in 1902 Fluidity test is accomplished in different ways [9]. For fluidity test different equipment has been developed and modified [10, 11]. The spiral-shaped mould test and the vacuum fluidity test nowadays are the most popular fluidity tests (see Figure 1). The spiral-shaped mould test is by measuring the length that the metal flowed inside a spiral-shaped mould and for vacuum test by using a vacuum pump measures the length the metal flowed inside a narrow channel when sucked from a crucible. Anyway, the spiral test has been widely used because it is compact and transportable thus it can be used easily in the foundry.
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Fluidity depends on many factors which can be classified as follows [12]: Metal variables: •
Chemical composition
•
Solidification range
•
Viscosity
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Heat of fusion
Mould and mould/metal variables: •
Heat transfer coefficient (coating)
•
Mould and metal thermal conductivity
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Mould and metal mass density
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Specific heat
•
Surface tension
Test variables: •
Applied metal head
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Channel diameter
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Casting temperature (superheat)
•
Oxide/particle content
Fig -1 Schematic representation of two fluidity tests: a) spiral test; b) vacuum test [13]. The first version of the equipment, which may be considered to represent a standard setup for spiral tests, consisted of a pouring basin, a rectangular tapered sprue in the cope, and a double spiral cavity in the drag. The spirals were moulded in quartz sand with an average grain size of 0.15 mm. The moulds were prepared manually with a phenolic binder (Alphaset). Figure 2 shows the pouring basin and the sand mould. The two Archimedian spirals, each with a cross section of 4 x 10 mm2, consisted of 3.5 turns, ISO 9001:2008 Certified Journal
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