Sains Malaysiana 31: 93-100 (2002)                                                                              Sains Fizis dan Gunaan /

Physical and Applied Sciences

Simulation of Thermodynamic Aspects

of AI-Si Binary System

Saheb Nouari, Abdul Razak Daud, Redzuwan Yahya

 & Shahidan Radiman

School of Applied Physics

Faculty of Science and Technology

Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E, Malaysia

ABSTRACT

It is possible to perform a thermodynamic analysis to a system by using thermodynamic models for the Gibbs energy of individual phases. As a result a thermodynamic data can be created for each system. The models are phenomenological involving empirical parameters which could be defined or estimated from experimental information. Once the Gibbs energy functions of phases in the system have been obtained, many thermodynamic properties may be calculated by applying standard thermodynamic relations. In the present study Thermo-Calc software was used for plotting the phase diagram of the Al-Si binary system and other property diagrams. A simulation of solidification process was also highlighted.

ABSTRAK

Analisis termodinamik boleh dilakukan pada sesuatu sistem dengan menggunakan model termodinamik bagi tenaga Gibbs fasa-fasa tertentu. Data termodinamik dapat diwujudkan bagi setiap sistem melalui hasil analisis ini. Model-model termodinamik menggambarkan fenomena yang dikaitkan dengan parameter empirik yang boleh ditakrif atau dianggar berdasarkan maklumat uji kaji. Apabila fungsi tenaga Gibbs bagi fasa-fasa dalam sistem diperolehi sifat-sifat termodinamik boleh dikira dengan menggunakan persamaan-persamaan termodinamik piawai. Dalam kajian ini perisian Thermo-Calc telah digunakan bagi melakar gambarajah fasa untuk sistem biner Al-Si dan gambarajah-gambarajah sifat yang lain. Simulasi bagi proses pemejalan juga dikemukakan.

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