Synthesis of Amorphous Al-based Alloy Powders by Mechanical Alloying and Mechanical Disordering

概要

論文の詳細を見る
Amorphous Al-based alloy powders have been synthesized by mechanical alloying (MA) of elemental Al and TM (TM; Ti, Zr, Nb and Ta), and mechanical disordering (MD) from crystalline intermetallic compound powders of Al_xTM_<1-x> respectively using both ball-milling (BM) and rod-milling (RM) techniques. The mechanically alloyed and mechanically disordered alloys were characterized by means of X-ray diffraction, scanning electron microscopy, electron probe microanalysis, transmission electron microscopy, differential thermal analysis, differential scanning calorimetry and chemical analysis. The results have shown that the crystal-to-amorphous transformation in the MD process occurs through one stage without compositional change, while the crystalline-to-amorphous formation in the MA process occurs through three stages with dramatic compositional change. At the early stage of the MA time, the starting elemental powders of Al and TM are agglomerated to form large composite particles , as large as 800 μm in diameter. These particles contain many thick layers of Al and TM metals. At the intermediate stage of the MA time, however, the powder particles are reduced in size and contain numerous narrow and well-arranged layers. During this stage of MA, a complete crystalline-to-amorphous phase transformation occurs by heating the alloy powders to about 700 K. This transformation occurs due to a thermally assisted solid-state amorphization (TASSA) between the elemental starting materials. Contrary to this, the formation of the amorphous phase at the final stage of the MA time occurs only due to the mechanically driven solid-state amorphization (MDSSA).amorphous alloyssolid state reactionmechanical alloyingmechanical disorderingpowder metallurgy
東北大学の論文
1994-03-25

Synthesis of Amorphous Al-based Alloy Powders by Mechanical Alloying and Mechanical Disordering

スポンサーリンク

概要

著者

関連論文

スポンサーリンク