Sıcak Presleme Yöntemi ile Üretilen Cu-Cr Alaşımlarının Sertlik ve Elektriksel İletkenlik Özellikleri Üzerine Mekanik Alaşımlama Süresinin Etkisi

Yıl 2022, Cilt: 12 Sayı: 1, 47 - 58, 01.06.2022

Hamza Çolak , Serhatcan Berk Akçay , Temel Varol , Onur Güler , Hüseyin Can Aksa

Öz

Yapılan bu çalışmada ağırlıkça %0,5 krom takviyeli bakır partiküllerin mekanik alaşımlama yöntemi ile farklı alaşımlama süreleri
kullanılarak alaşımlandırılması ve üretilen tozların sıcak pres yöntemiyle yoğunlaştırılması çalışmaları yer almaktadır. Mekanik
alaşımlama parametreleri olarak 10:1 bilye:toz oranı, 400 dev/dk dönüş hızı seçilmiştir süreler ise değişken olarak 0, 0,5, 1, 2 ve 4 saat
olacak şekilde belirlenmiştir. Sıcak presleme parametreleri tüm deneylerde sabit olarak kullanılmıştır ve 500 ⁰C ve 600 MPa olarak
belirlenmiştir. Yapılan deneyler neticesinde başlangıçta küresel ve düzensiz morfolojiye sahip tozların 0,5 saat mekanik alaşımlama
işlemi sonrasında pulsu benzeri morfolojiye sahip olduğu belirlenmiştir. Ayrıca yapılan deneyler sonucunda en yüksek spesifik yüzey
alanı 1 saat mekanik alaşımlama işlemi neticesinde elde edilmiştir ve 0,0667 m2/g olarak ölçülmüştür. Bu çalışma kapsamında üretilen
kompakt numunelerin en düşük ve en yüksek sertlik değerleri sırasıyla mekanik alaşımlama işlemi uygulanmamış ve 1 saat mekanik
alaşımlama işlemine tabii tutulmuş numunelere aittir ve 71,97 HB ve 99,12 HB olarak ölçülmüştür. En yüksek elektriksel iletkenlik
değeri de 4 saat mekanik alaşımlama işlemine tabii tutulmuş numuneye aittir ve 91,27 %IACS olarak ölçülmüştür. Yapılan bu çalışma
ile mekanik alaşımlama işlem parametrelerinden biri olan sürenin parçacıkların morfolojisi ve boyutu ile kompakt malzemenin
mikroyapısı ve fiziksel ve mekanik özellikleri üzerine etkileri belirlenmiştir.

Anahtar Kelimeler

Bakır, Krom, Mekanik Alaşımlama, Sıcak Presleme, Toz Metalurjisi

Teşekkür

Bu çalışmanın yazarlarından Hamza ÇOLAK, Yükseköğretim Kurulu tarafından desteklenen 100/2000 YÖK programında doktora bursiyeri olarak desteklenmektedir. Yazarlar, desteklerinden dolayı Yükseköğretim Kurulu 100/2000 YÖK programına teşekkür eder.

The Effect of Mechanical Alloying Time on the Hardness and Electrical Conductivity Properties of Cu-Cr Alloys Produced by Hot Pressing Method

Öz

This study concentrated on alloying 0.5% chromium reinforced copper particles by weight by mechanical alloying method according
to different alloying times and intensifying the produced powders by hot press method. 10:1 ball:powder ratio and 400 rpm rotation
speed were selected as mechanical alloying parameters and the times were determined as 0, 0.5, 1, 2 and 4 hours as variable. Hot
pressing parameters were used as constant in all experiments and were determined as 500 ⁰C and 600 MPa. As a result of the
experiments, it was determined that the powders with initially spherical and irregular morphology had a flake-like morphology after
0.5 hours of mechanical alloying. In addition, as a result of the experiments, the highest specific surface area was obtained after 1 hour
of mechanical alloying and was measured as 0.0667 m2/g. The lowest and highest hardness values of the compact samples produced
within the scope of this study belong to the samples that were not mechanically alloyed and subjected to 1 hour mechanical alloying,
respectively, and were measured as 71.97 HB and 99.12 HB. The highest electrical conductivity value belongs to the sample subjected
to mechanical alloying process for 4 hours and it was measured as 91.27% IACS. In this study, the effects of time, which is one of the
mechanical alloying process parameters, on the morphology and size of the particles, the microstructure and physical and mechanical
properties of the compact material were determined.

Anahtar Kelimeler

Copper, Chromium, Mechanical Alloying, Hot-Pressing, Powder Metallurgy

Kaynakça

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