Toz metalurjisi ile üretilen 17-4 pH paslanmaz çelik malzemelerde, alaşım elementlerinin aşınma davranışı üzerindeki etkisinin incelenmesi
Küçük Resim Yok
Tarih
2019
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Karabük Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu çalışmada, toz metalurjisi yöntemi ile farklı oranlarda molibden, tantalyum ve titanyum ilave edilerek üretilen 17-4 PH paslanmaz çelik alaşımların kuru kayma aşınma davranışları incelenmiştir. Hazırlanan alaşım tozlar soğuk preslenerek (800 MPa) ham numuneler üretilmiştir. Üretilen green kompaktlar 10-6 milibar vakumda 1300 °C'de 1 saat sinterlenerek, fırın ortamında oda sıcaklığına soğutulmuştur. Daha sonra tantalyum ve titanyum ilave edilen numuneler 480 °C'de vakumlu fırın ortamında 1, 4 ve 8 saat yaşlandırmaya tabi tutulmuştur. Sonra molibden (Mo), tantalyum (Ta) ve titanyum (Ti) ilave edilen numuneler taramalı elektron mikroskobu (SEM+EDS), X-ışını kırınımı (XRD), yoğunluk ve sertlik ölçümleri ile incelenmiştir. Aşınma testlerinde pin-on-disk cihazı kullanılmıştır. Aşınma testlerinde parametre olarak 0,8 msn-1 kayma hızı, 30 N ve 45 N yük ve beş farklı kayma mesafesi (600, 1200, 1800, 2400 ve 3000 m) kullanılmıştır. Yapılan çalışmalar sonucunda, farklı oranda Mo ilave edilen (% 0,5 - % 1- % 2 - % 4) 17-4 PH paslanmaz çeliğin yoğunluklarının artan % Mo oranıyla birlikte arttığı, sertliklerinin ise azaldığı belirlenmiştir. İlaveten, 17-4 PH paslanmaz çeliğin alaşımlarında, Mo miktarındaki artışa paralel olarak ağırlık kayıplarının da arttığı belirlenmiştir. Yine, farklı oranda Ta ilave edilen (% 0,15 - % 0,30 - % 0,45 - % 0,60) 17-4 PH paslanmaz çeliğin yoğunluklarının, aynı şekilde sertliklerinin, artan % Ta oranıyla birlikte ve en çok 8 saat yaşlandırma süresi sonunda arttığı belirlenmiştir. 17-4 PH paslanmaz çeliğin alaşımlarında, Ta miktarındaki artışın tersine ağırlık kayıplarının azaldığı tespit edilmiştir. Ayrıca, farklı oranda Ti ilave edilen (% 0,5 - % 1- % 1,5 - % 2) 17-4 PH paslanmaz çeliğin yoğunluklarının artan % Ti oranıyla birlikte azaldığı, sertliklerinin ise arttığı ve 17-4 PH paslanmaz çeliğin alaşımlarında, Ti miktarındaki artışın tersine ağırlık kayıplarının azaldığı belirlenmiştir. Anahtar Kelimeler : 17-4 PH paslanmaz çelik, molibden, tantalyum, titanyum, toz metalurjisi, aşınma davranışı.
In this study, dry slip wear behaviors of 17-4 PH stainless steel alloys produced by adding molybdenum, tantalum and titanium in different ratios by powder metallurgy method were investigated. The prepared alloy powders were cold pressed (800 MPa) and green samples were produced. The produced green compacts were sintered in 10-6 millibars under vacuum for 1 hour at 1300 °C and cooled to room temperature in the oven environment. Tantalum and titanium added samples were then subjected to aging for 1, 4 and 8 hours in a vacuum oven environment at 480 °C. Then, molybdenum (Mo), tantalum (Ta) and titanium (Ti) added samples were examined by scanning electron microscopy (SEM + EDS), X-ray diffraction (XRD), density and hardness measurements. Pin-on-disk device was used in wear tests. In the wear tests, a sliding speed of 0,8 msec-1, 30 N and 45 N load, and five different sliding distances (600, 1200, 1800, 2400 and 3000 m) were used as parameters. As a result of the studies, it was determined that the density of 17-4 PH stainless steel increased with increasing Mo ratio and the hardness decreased with the addition of different amount of Mo (0.5 % - 1 % - 2 % - 4 %). In addition, it was determined that weight losses increased in parallel with the increase in the amount of Mo in the alloys of 17-4 PH stainless steel. Beside, It was determined that the densities of 17-4 PH stainless steel, which are added in different ratio Ta (0,15 % - 0,30 % - 0,45 % - 0,60 %), likewise their hardness, with increasing Ta % ratio increased end of the aging period up to 8 hours. Also, it was determined that weight losses were decreased in contrast to the increase in the amount of Ta in the alloys of 17-4 PH stainless steel. In addition, it was determined that the densities of 17-4 PH stainless steel decreased with increasing Ti % and hardness increased with the addition of different amount of Ti (0.5 % - 1 % - 1.5 % - 2 %) and the weight losses decreased in contrast to the increase in the amount of Ti in the alloys of 17-4 PH stainless steel. Key Words : 17-4 PH stainless steel, molybdenum, tantalum, titanium, powder metallurgy, wear behavior.
In this study, dry slip wear behaviors of 17-4 PH stainless steel alloys produced by adding molybdenum, tantalum and titanium in different ratios by powder metallurgy method were investigated. The prepared alloy powders were cold pressed (800 MPa) and green samples were produced. The produced green compacts were sintered in 10-6 millibars under vacuum for 1 hour at 1300 °C and cooled to room temperature in the oven environment. Tantalum and titanium added samples were then subjected to aging for 1, 4 and 8 hours in a vacuum oven environment at 480 °C. Then, molybdenum (Mo), tantalum (Ta) and titanium (Ti) added samples were examined by scanning electron microscopy (SEM + EDS), X-ray diffraction (XRD), density and hardness measurements. Pin-on-disk device was used in wear tests. In the wear tests, a sliding speed of 0,8 msec-1, 30 N and 45 N load, and five different sliding distances (600, 1200, 1800, 2400 and 3000 m) were used as parameters. As a result of the studies, it was determined that the density of 17-4 PH stainless steel increased with increasing Mo ratio and the hardness decreased with the addition of different amount of Mo (0.5 % - 1 % - 2 % - 4 %). In addition, it was determined that weight losses increased in parallel with the increase in the amount of Mo in the alloys of 17-4 PH stainless steel. Beside, It was determined that the densities of 17-4 PH stainless steel, which are added in different ratio Ta (0,15 % - 0,30 % - 0,45 % - 0,60 %), likewise their hardness, with increasing Ta % ratio increased end of the aging period up to 8 hours. Also, it was determined that weight losses were decreased in contrast to the increase in the amount of Ta in the alloys of 17-4 PH stainless steel. In addition, it was determined that the densities of 17-4 PH stainless steel decreased with increasing Ti % and hardness increased with the addition of different amount of Ti (0.5 % - 1 % - 1.5 % - 2 %) and the weight losses decreased in contrast to the increase in the amount of Ti in the alloys of 17-4 PH stainless steel. Key Words : 17-4 PH stainless steel, molybdenum, tantalum, titanium, powder metallurgy, wear behavior.
Açıklama
Fen Bilimleri Enstitüsü, Makine Eğitimi Ana Bilim Dalı
Anahtar Kelimeler
Metalurji Mühendisliği, Metallurgical Engineering
