Al-Zn-Mg-Cu alaşımlarının su verme hassasiyeti

Yıl 2017, Cilt: 23 Sayı: 8, 963 - 966, 28.12.2017

Funda Gül Koç , Mustafa Çöl Tanju Çeliker

Öz

Al-Zn-Mg-Cu
alüminyum alaşımları sahip oldukları düşük yoğunluk, yüksek mukavemet, sertlik,
tokluk ve korozyon direnci özelliklerinden dolayı havacılık ve uzay
endüstrisinde geniş bir kullanım alanına sahiptir.  Bu çalışmada, 7075 serisi alüminyum alaşımının
su verme hassasiyeti alın su verme yöntemi kullanılarak incelenmiştir. Numuneye
480 °C’de 3 sa. süreyle çözeltiye alma işlemi uygulandıktan hemen sonra alın su
verme test düzeneğinde oda sıcaklığındaki su ile bir uçtan soğutma işlemi
uygulanmıştır. Soğutma işlemi esnasında numunenin boyuna kesiti boyunca meydana
gelen soğuma hızındaki değişimler K tipi termo-elemanlar vasıtasıyla eş zamanlı
olarak ölçülmüştür. Su verme işlemi sonrası numuneye 120 °C’de 24 sa. süre ile
suni yaşlandırma işlemi uygulanmıştır. Su verilen uçtan uzaklaştıkça malzemenin
sertlik, elektriksel iletkenlik ve mikroyapı özeliklerinde meydana gelen
değişimler incelenmiştir.

Anahtar Kelimeler

Su verme hassasiyeti, Al-Zn-Mg-Cu alaşımları, Sertlik, Elektriksel iletkenlik, Mikroyapı

Quench sensitivity of Al-Zn-Mg-Cu alloys

Öz

Al-Zn-Mg-Cu
aluminum alloys are extensively used in aviation and aerospace industries for
their high strength, hardness, toughness and corrosion resistance. In this
study, quench sensitivity of 7075 series aluminum alloy was investigated by
using end quench test. Specimens were solution treated at 480 °C for 3 hours
and then the specimens were immediately transferred to the end quenching rig
(<5s). Changes in the temperature of the specimen during the quenching process
were measured by using type K thermocouples. Quenched specimen was subjected to
artificial aging at 120 °C for 24 hours. The changes of hardness, electrical
conductivity and microstructure properties of the material as the distance from
quenched end of bar increases were investigated.

Anahtar Kelimeler

Quench sensitivity, Al-Zn-Mg-Cu alloys, Hardness, Electrical conductivity, Microstructure

Kaynakça

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