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technique could be developed to replace metallography as the primary control tool [ 3 ]. Thermal analysis as a technique is used to evaluate the melt quality. By this method, some characteristic values are extracted from a cooling curve and/or its

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well. Thermal analysis has been gaining increasing acceptance in many aluminium foundries as a faster, online process control, non-destructive and quantitative technique [ 7 ] that can be used before casting [ 8 ]. Computer-aided cooling curve

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plotted on temperature–composition equilibrium (phase) diagrams. The non-equilibrium cooling curve method is useful for commercial applications for a number of reasons: it is simple, inexpensive, and provides consistent rapid results for all

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samples of indium ( T fus = 156.6 °C, Δ fus H = 3.266 kJ mol −1 ) and n -dodecane ( T fus = −9.65 °C, Δ fus H = 36.918 J mol −1 ). The temperature and heat flow uncertainties were estimated to be ±0.1 °C and ±0.05 mW, respectively. DSC cooling curves

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, thermal analysis became an important tool to reflect the solidification behaviour of foundry alloys, ferrous and non-ferrous [ 5 – 18 ]. The cooling curve itself, as well as its derivatives and related temperatures, and calculated parameters provide

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Abstract  

A data acquisition system and the SAD2 software, that provide characteristic cooling curves, in combination with microstructure analysis were used to study precipitates formation in the AA380.0 aluminium alloys modified by adding extra magnesium. The samples were solidified with distinct cooling rates caused by carrying out the solidification in shell and permanent molds. The mathematics processing of the cooling curves in agreement with the microstructure analysis have confirmed the remarkable presence of both the Al–Si dendrite network and the Mg2Si interdendritic phase in the alloys with the addition of extra magnesium.

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Abstract  

Recycling of aluminum scrap has gained interest owing to its economic and ecological benefits. Unfortunately, during the collection of scrap from a mixer of junk from various sectors it is difficult to ensure that the recycled alloy has the same chemical composition as that of already existing commercial alloys. Consequently, some of the alloying elements become trace/tramp elements in the recycled alloy. Therefore, in order to obtain high performance recycled alloys, controlling the impurity levels of the aluminum melt is of vital importance. Normally, computer aided cooling curve analysis (CA-CCA) is used to find the relationship between cooling curve parameters, melt treatments, alloy composition, and properties. In the present study, the first differential thermal analysis (DTA) approach has been used to detect and quantify impurity elements in scrap-like liquid aluminum alloys.

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Abstract  

The curves of heating and cooling crystalline lanthanum nitrate were registered and numerical differentiation was carried out. The first derivatives of kinetic curves expressed as the temperature function make it possible to carry out comparative studies of dissolution and crystallization. Superposition of relative water concentration scale on the third derivative of heating and cooling curves make the analysis of stoichiometry and mechanism of hydration changes possible in the solid phase and saturated solutions.

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Abstract  

Results of the thermodynamic investigations in the Bi–GaSb system are presented in this paper. Thermodynamic characteristics experimentally determined by Oelsen's calorimetric method were compared with values predicted by different thermodynamic predicting methods (general solution model, Kohler, Muggianu, Toop, Hillert) at the temperature of 1073 K. Also, based on the obtained cooling curves and microstructure analysis of the investigated samples by optical microscopy, phase diagram of the Bi–GaSb system was investigated and compared with literature data.

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Abstract  

Results of the comparative thermodynamic analysis of the Bi-Ga0.1Sb0.9 section in theBi-Ga-Sb system are given in this paper. Experimental calorimetric investigations were done according to Oelsen's method, while for the thermodynamic prediction Chou's general solution model was applied. Activities, activity coefficients, partial molar quantities for bismuth and integral molar quantities were obtained at a temperature of 1073 K. Based on obtained cooling curves, DTA and SEM results for the investigated samples, phase diagram of the investigated section is constructed and presented in this paper, too.

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