Politeknik Dergisi 2147-9429 Gazi Üniversitesi 10.2339/politeknik.389617 Engineering Mühendislik Mekanik Olarak Sentezlenen NiTi + Zn Tozlarının Karakterizasyonu ve Sinterlenelebilirliğinin Araştırılması Investigation of Characterization and Sinterability of Mechanically Synthesized NiTi + Zn Powders Aksöz Sinan Bostan Bülent 06 01 2018 21 2 437 443 08 05 2017 Copyright © 1998, Politeknik Dergisi 1998 Politeknik Dergisi

Bu çalışmada; önalaşımlı NiTitozları ve % 2, % 4, % 6, % 8 ve % 10 Zn toz oranları kullanılarak bilyelideğirmende 60 dakika mekanik öğütme işlemine tabi tutulmuştur. Öğütülen NiTi +Zn toz karışımları 750 MPa basınç altında presleme sonrası 1000°C’de 60 dakikasinterlenmiştir. Öğütülen ve presleme sonrası sinterlenen numuneleremikroyapısal değişiklikleri tespit etmek için; Taramalı Elektron Mikroskobu(SEM), Element Dağılım Spektrometresi (EDS), Diferansiyel Taramalı Kalorimetre(DSC) ve X-Ray (XRD) analizleri uygulanmıştır. NiTi + Zn toz karışımlarındaartan Zn oranına bağlı olarak, toz morfolojisinde değişiklikler tespit edilmişve özellikle % 10 Zn ilave edilen tozlarda öğütme sonrası NiTi tozlarınınyüzeyini homojen bir şekilde tamamen kapladığı tespit edilmiştir.  NiTi + Zn tozlarının 1000°C’de 60dakika sinterleme sonrası Zn’nin sıvı faz sinterlenmesi ile yapıda NiTitozlarının arasında bir bağ oluşmuş ve böylece düşük sıcaklıklarda sinterlenmeişlemi gerçekleştirilebilmiştir. Ayrıca; NiTi + % 10Zn içeriği ile homojen vepürüzsüz bir mikro yapı elde edilmiştir.  

In this study; prealloyed NiTi powders and ball millswith 2%, 4%, 6%, 8% and 10% Zn powder ratios were subjected to mechanicalmilling for 60 minutes. The milled NiTi + Zn powder mixtures were pressed under750 MPa pressurize and then sintered at 1000°C for 60 minutes. In order to determinethe microstructural changes in the samples which were milled, pressed and thensintered samples; SEM, EDS, DSC and XRD analyses were applied, respectively.Changes in powder morphology were observed, depending of the increasing Zncontent in the NiTi + Zn powder mixtures and it was determined that the powderscontaining 10% Zn completely covered the surface of the NiTi powders in ahomogeneous manner after milling.Zn content in the micro structure also provided the alloy to be sinteredat low temperatures by completely filling the gaps and pores after thesintering process at 1000°C for 60 min. In addition, a homogenous and smoothmicrostructure was obtained with NiTi + 10Zn% content.

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