Eşit kanallı açısal preslenmiş toz halde Al-%5Ni alaşımının mikro yapısal karakterizasyonu

Bu çalışmanın amacı eşit kanallı açısal presleme yöntemiyle (EKAP) toz halde Al-%5Ni alaşımını pekiştirmektir. Saf Al ve ağırlıkça %5 saf nikel tozlarına 200°C'de 5-15 geçişli EKAP yöntemi uygulanmıştır. EKAP geçiş sayısının artışıyla, Al matriste Ni parçacıkları homojen olarak dağılmıştır ancak, Al matriste Ni'in tam olarak çözünebilirliğinin etkili olmadığı görülmüştür. EKAP işleminin geçiş sayıları artışıyla ortalama tane boyutu düşmüştür. 5 geçişli ECAP işlemiyle tane incelmesi başlangıç iri Al tozlarının kıyılarında (Al parçacıklar arasında) başlamışken, 15 geçişli EKAP işlemiyle daha ince ve uzamış taneler elde edilebilmiştir. Numunelerin ortama yoğunlukları ve HV0,5 mikro sertlikleri sırasıyla 2,7 g/cm3 ve 61 olarak sağlanmıştır. Bu EKAP şartlarında belirgin bir Al-Ni intermetalik fazları sağlanmamıştır

Microstructural characterization of equal-channel angular-pressed as powder Al-5% Ni alloy

The aim of this study was to consolidate of powders mixed Al-Ni through equal channel angular pressing (ECAP). Pure Al and 5 % (in wt.) Ni powders were exposed to ECAP with 5-15 passes procedure at 200°C. With the increasing ECAP passes, Ni particles distributed in the Al matrix homogeneously and the solubility of Al in the Ni particles increased relatively. However, it was seen that Ni solubility in the Al matrix wasn’t sufficient. The average grain size reduced with the increasing pass numbers of the ECAP process. While grain refinement started forming at the edge of initial large Al powder (inter-particles of Al) after applying 5-pass ECAP, finer and elongated grains were obtained after the 15 - pass ECAP process. Average densities and HV0,5 micro hardness of the specimens were found as 2,7 g.cm-3 and 61 respectively. In these conditions of ECAP, Al-Ni intermetallic phases wasn’t distinct formed

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