Effect of Mish Metal Cerium Addition on Fluidity of Aluminum Eutectic Silica Alloys - LM6

Abstract

The evaluation of 0.1 to 1.0% of Ce addition effect on fluidity has been investigated. The fluidity of LM6 has decreased with the Ce addition. The effect of Ce can be shown very clearly with a high amount of 1% wt of Ce. The fluidity length of the composites is shorter than that of the LM6 base material. In spiral mold, the fluidity length is shortened when the weight percentage of Ce content is increased in the base metal LM6. Optical microscope images showed that the 1.0 % of Ce additive led to modification of silica morphology which reduced the fluidity length to 28%. The partial modification of silica can be observed clearly in small amount of Ce but it does not have large affect on the fluidity length.

Effect of Lanthanum Addition on Fluidity of Complex Al-11Si-Cu-Mg Cast Alloy

“…The modification occurred due to the solid solubility of La in the aluminium and it is found to be further reduced in the presence of Si and Mg [10]. An increase in the La content above its solid solubility would only cause precipitation of La or the formation of an intermetallic compound Al-La and Al-Si-Cu-La [11,12]. The refiner of silica has a significant effect on fluidity and solidification rate [13,14].…”

Effect of High Cerium and Lanthanum on Impact Toughness of Al-11Si-Cu Eutectic Cast Alloy

“…The high level of Ce or La at 1.0 wt. % can modifier the Si particles by reducingthe size of Si particles of Al-11Si-Cu cast alloy but never change the morphology to fibre structure [11,12]. The Sr-Mg interaction is known to reduce the porosity volumefraction of Al-Si-Cu alloys .The addition of both Mg and Sr can lead to severe segregation of the Al2Cu phase in 319.2 alloys, resulting in large amounts of the coarse block-like phase, com-pared to the finer eutectic-like form.…”

“…The modification efficiency of the mechanical properties of A356 alloy with 1.0wt % La is similar to that of the commercial modifier Sr [8].The small amount of Ce also had improved tensile strength of A360 alloys with 0.01 wt.% [9].Intermetallic compounds have very strongly effective on mechnincal properties , Depending upon alloy composition and solidification conditions, iron can form various intermetallic compounds, such as a-Al 15 (Fe,Mn) 3 Si 2 or Al 8 Fe 2 Si (in Al-Si-Mg alloys), ß-Al5FeSi, or л-Al 8 FeMg 3 Si 6 . Another negative effect of iron is that it reacts with Cu to form Cu2FeAl7, thus reducing the effective Cu content of the alloy [10].The additions of Ce, La significantly change the characteristic parameters of the Al-Si eutectic phase and reduced the particles size of Si [11] while had negative effecting on fluidity of Al-Si-Cu cast alloy [12].Charpy impact testing was thus chosen for use in this study while this particular test has always been found to be extremely susceptible to the addition of alloying elements and to silicon morphology, despite the fact that data on impact properties is comparatively rare for these alloys. According to prior studies, impact strength is the most sensitive of all the mechanical properties to silicon content for alloy compositions containing 3-15% Si [13]In this research the Al-11Si-Cu alloys was used as based alloy.…”

The Effect of Chromium Addition on Fluidity, Microstructure and Mechanical Properties of Aluminium LM6 Cast Alloy

“…Quantitatively fluidity is determined by measuring the distance of metal flowing through mould channel with small cross section. The spiral test has been extensively used because it is compact and portable, and hence can be used easily in the foundry [11]. Sludge formation not only changes the chemical composition of the molten metal, but also diminishes the castability of molten metal.…”