Santrifüj Döküm Yöntemiyle Üretilen Al-Cu Fonksiyonel Derecelenmiş Malzemelerde Üretim Parametrelerinin Malzemenin Sertliği Üzerine Etkisi

Yıl 2017, Cilt: 20 Sayı: 1, 121 - 127, 01.03.2017

Semih Ağca Neşet Akar

Öz

Bu çalışmada, soğuma hızı (0,27 – 7,38 – 14,23 – 21,56 °C/s), kalıp dönme hızı (160 – 225 – 275 rpm) ve döküm atmosferi (açık atmosfer – vakum atmosferi) parametrelerinin santrifüj döküm yöntemiyle üretilen Al-Cu fonksiyonel derecelendirilmiş malzemelerin (FDM) sertliği üzerine etkisi araştırılmıştır. Yapılan deneysel araştırmalar sonucunda, soğuma hızının artması ile sertlik değerinin arttığı ve diğer parametrelerin etkisinin soğuma hızına bağlı olarak farklılık gösterdiği tespit edilmiştir. Yüksek (7,38 – 14,23 – 21,56 °C/s) soğuma hızlarında üretilen döküm parçaların bütün bölgelerinde, kalıp dönme hızı arttıkça sertlik artmış ve açık atmosferde üretilen numunelerin sertliği vakum atmosferinde üretilenlerden daha yüksek çıkmıştır. Düşük (0,27 °C/s) soğuma hızında ise, kalıp dönme hızı arttıkça sertlik, numunenin dönme merkezine uzak bölgesinde artmış, orta bölgede değişmemiş ve dönme merkezine yakın bölgesinde de azalmıştır. Bununla birlikte, açık atmosferde üretilen numunelerin sertliği merkeze uzak bölgede vakum ortamında üretilenlerden daha düşük, orta bölgede aynı ve merkeze yakın bölgede de daha yüksektir. Bu sonuçlar santrifüj döküm yöntemiyle FDM üretiminde, üretim parametrelerinin birbirleri ve malzemenin sertliği üzerine etkisi olduğunu göstermektedir.

Anahtar Kelimeler

FDM, Santrifüj Döküm, Sertlik

Effect of Fabrication Parameters on Hardness of Al-Cu Functionally Graded Materials Manufactured by Centrifugal Casting

Öz

In this study, the effect of cooling rate (0,27 – 7,38 – 14,23 – 21,56 °C/s), mold rotation speed (160 – 225 – 275 rpm), and casting atmosphere (air – vacuum) on hardness of Al-Cu functionally graded materials (FGMs) were investigated. According to the experimental results, it was found that the hardness value became higher with increasing cooling rate and efficiency of other parameters varied according to cooling rate. The hardness increased with increasing mold rotation speed and hardness values of specimens produced in air atmosphere are higher than that of manufactured in vacuum atmosphere for all parts of specimens produced in high (7,38 – 14,23 – 21,56 °C/s) cooling rates. On the other hand, the specimens produced in low cooling rate (0,27 °C/s) have varying hardness values depending on the location of the cast part. Hardness increased with increasing mold rotation speed in the far part of specimens to the rotation axis. It remained unchanged in middle section and decreased with increasing mold rotation speed in parts close to the rotation axis. Also, hardness values of specimens obtained in air atmosphere are lower in far part, same in middle and higher in rotation axis by comparison with the specimens obtained in vacuum atmosphere. Results showed that all parameters affected each other and the hardness in fabrication of FGMs by centrifugal casting.

Anahtar Kelimeler

FGMs, Centrifugal Casting, Hardness

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