Bor İlavesinin Toz Metal D2 Takım Çeliğinin Mikroyapı ve Mekanik Özelliklerine Etkisi

Öz

Bu çalışmada, toz metalurjisi (T/M) yöntemi ile üretilen D2 takım çeliğinin mikroyapı ve mekanik özelliklerine B ilavesinin etkileri incelenmiştir. D2 takım çeliği tozunun içerisine ağırlıkça %0,5-2 arasında farklı oranlarda amorf B ilavesi yapılarak elde edilen toz karışımları 700 MPa basınç uygulanarak şekillendirilmiştir. Bor ilavesinin sinterleme davranışına etkisini tespit etmek amacıyla şekillendirilen ham numuneler farklı sıcaklıklarda sinterlenmiştir. En yüksek yoğunlaşmayı sağlayan sinterleme parametrelerini tespit etmek amacıyla yoğunluk ölçümleri gerçekleştirilmiştir. Optimum şartlarda sinterlenen numunelerin mikroyapı ve mekanik özellikleri incelenmiştir. Mikroyapı incelemeleri X-ışınları analizi (XRD), taramalı elektron mikroskobu (SEM) ve enerji dağılımı spektrometresi (EDS) ile gerçekleştirilmiştir. Mekanik özelliklerin belirlenmesinde sertlik ölçümlerinden yararlanılmıştır. Sonuçlar, belirli bir orana kadar B ilavesinin, daha düşük sinterleme sıcaklıklarında daha yüksek bağıl yoğunluk değerleri sağladığını göstermiştir. XRD analizleri ve SEM incelemeleri, B oranındaki artışın M23C6 tipi karbürlerin M23(C,B)6 boro-karbürlere dönüşmesine yol açtığını göstermiştir. B oranındaki artışla birlikte üretilen çelik malzemelerin sertlik değerlerinde artış olduğu belirlenmiştir.

Anahtar Kelimeler

• D2 takım çeliği,Bor ilavesi,Yoğunluk,Mikroyapı,Sertlik

Kaynakça

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