Ümit Gencay BAŞCI, Hasan İsmail YAVUZ, Rıdvan YAMANOĞLU

Al6061 Talaşının Toz Metalurjisi ile Geri Kazanımı

Son yıllarda endüstrinin gelişmesi çevre kirliliğinin artmasında büyük rol oynamıştır. Çevrenin korunması amacıyla özellikle metalik atıkların geri dönüştürülmesi her geçen gün daha fazla dikkat çekmektedir. Bu nedenle özellikle talaş formundaki alüminyum atıklarının düşük enerji ve minimum emisyon ile geri kazanımını sağlayan katı hal yöntemleri tercih edilmeye başlanmıştır. Bu çalışmada, toz metalurjisi ile Al6061 talaşının vakum ortamında (10-4mbar), 30 MPa basınç altında ve farklı sıcaklıklarda (560, 580 ve 600°C), 15 dakika sinterlenerek katı hal geri kazanımları amaçlanmıştır. Sinterleme sıcaklığının malzeme özellikleri üzerindeki etkisinin incelenmesi için üretilen numunelerin Arşimet prensibine göre yoğunlukları ölçülerek, aşınma, sertlik ve eğme testlerine tabi tutulmuştur. Test sonuçları değerlendirildiğinde en yüksek yoğunluk (%97,8) 600°C’de sinterlenen numunede elde edilmiştir. Yoğunluk değerlerinin artış göstermesi mekanik özellikleri de doğrudan etkilemiştir. En yüksek sertlik değeri 58,9 HV ile 600°C’de sinterlenen numunede ölçülmüştür. Artan yoğunluk ve sertlik ile aşınma direncinde artış gözlenmiştir. Eğme testi sonucunda en yüksek eğme mukavemeti 348 MPa ile yine 600°C’de sinterlenen numunede ölçülmüştür. Sonuç olarak sıcak pres yöntemi ile 6061 talaşının katı hal geri kazanımları sağlanmış ve yüksek mukavemetli parça üretiminin mümkün olabileceği ortaya konmuştur.

Anahtar Kelimeler:

Al6061, Geri Kazanım, Toz Metalurjisi, Mikroyapısal Karakterizasyon, Mekanik özellikler, Talaş

Recycling of Al6061 Chip by Powder Metallurgy

In recent years the development of industry has played a significant role in the increase of environmental pollution. In order to protect the environment, the recycling of metallic wastes is getting more and more attention day by day. For this reason, solid-state methods, which provide the recycling of aluminum waste, especially in the form of chips with low energy and minimum emission, have started to be preferred. In this study, solid-state recycling was aimed by sintering Al6061 chips in a vacuum environment under 10-4 mbar, 30 MPa pressure and at different temperatures (560, 580 and 600C) for 15 minutes by powder metallurgy. In order to examine the effect of sintering temperature on material properties, the densities of the produced samples were measured according to the Archimedes principle, and they were subjected to wear, hardness and bending tests. When the test results were evaluated, the highest density was obtained in the sintered sample at 600°C with a relative density of 97,8%. The increase in density values also directly affected mechanical properties. The highest hardness value was measured in the sample sintered at 600°C with 58.9 HV. Wear performance increased with increasing hardness ratio. As a result of the bending test, the highest bending strength was measured at 348 MPa in the sample sintered at 600°C. Consequently, solid-state recovery of Al6061 chips was achieved by the hot press method, and it was demonstrated that it is possible to produce high-strength parts as well as material shaping.

Keywords:

Al6061 alloy, Recycling, Microstructural characterization, Mechanical properties, Chip, Powder metallurgy,

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