Sains Malaysiana 30: 195-202 (2001)                                                                           Sains Fizis dan Gunaan /

Physical and Applied Sciences

Effects to Magnesium addtion on Microhardness

in Eutectic Al-Si-Mg Alloys

Abdul Razak Daud & Ibrahim Abu Talib

Pusat Pengajian Fizik Gunaan

Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E.,Malaysia

Mohd bin Harun

Institut Penyelidikan Teknologi Nuklear Malaysia

43000 Kajang, Selangor D.E.,Malaysia

ABSTRACT

The eutectic Al-Si-Mg alloys were prepared and heat treated at 327^oC and 540^oC for 10 hours and followed by ageing at 160^oC for various ageing times.  The microhardness of the alloys increased as the ageing time and magnesium content increased.  The addition of magnesium as well as ageing strengthened the matrix and improved the second phase morphology.

ABSTRAK

Aloi-aloi Al-Si-Mg eutektik telah disediakan dan dirawat haba pada suhu 327^oC dan 540^oC selama 10 jam dan seterusnya dilakukan penuaan pada suhu 160^oC bagi beberapa tempoh tertentu.  Mikrokekerasan aloi berkenaan telah meningkat apabila tempoh penuaan dan kandungan magnesium ditingkatkan.  Penambahan magnesium dan juga penuaan telah menguatkan matrik dan memperbaiki lagi morfologi fasa kedua.

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