Effect of post-heat treatment on microstructure and mechanical properties of cu-fe-co powder alloy fabricated by hot pressing

In this study, the powder mixture which consists of Cu-Fe-Co was produced by using the method of hot pressing technique. In addition, effect of heat treatment process on microstructure and mechanical properties of this alloy was investigated. Following the hot pressing process applied on the samples, heat treatment was carried out at 950°C for two different dwelling times (90 and 180 minutes). Measured density values were considered as physical characteristics, while hardness and fracture strength values were considered as mechanical characteristics. It was observed that porosity rates of hot pressed samples were decreased by increasing of temperature and pressing parameters. In this study it was observed that Cu was spread in matrix and filled the micro porosities. Hardness values were determined to be decreased as a result of grain growth after heat treatment process. That 4 fold increased elongation % values which were achieved by TRS experiments were observed as well

The effect of porosity and cu rate on microstructure and mechanical properties of co alternative powder metallurgy compound

Cu-Ni-MX1480 powder compound were prepared at six different alloy ratios and cold pressed with a pressure of 300 MPa. Then 12 samples were obtained by hot pressing at 700 оC with 20 MPa pressure and at 800 oC with 30 MPa pressure for 4 minutes in a vacuum atmosphere hot pressing machine. Porosity ratios of samples were calculated by the different between theoretical density and measured density of samples. Effect of porosity on microstructure and mechanical properties were investigated by performing SEM, XRD, hardness measurements and TRS tests. It was observed that as a result of increased hot pressing parameters and increased Cu ratio, porosity ratio was decreased and better mechanical properties achieved

Türkiye Florası İçin Yeni Bir Akhatmi Kaydı: Kitaibela vitifolia Willd. (Ebegümecigiller / Malvaceae)

Bu çalışmada, Kitaibela vitifolia Willd. Türkiye Florası için ilk kez kaydedildi. Bu tür, EskiYugoslavya ve Arnavutluk’ta doğal, dar yayılışlı bir endemik olup, Macaristan ve Romanya’dakültür formundadır. Amanos Dağları’nda (Osmaniye) biyoçeşitlilik projesi kapsamındagerçekleştirilen arazi çalışmaları sırasında bu tür çam ormanı açıklıklarında görüldü veörnekler fotoğraflandı. Bu örnekler herbaryum materyali haline getirmek için toplandı.Türkiye Florası ve ilişkili flora eserleri kontrol edildikten sonra, bu örneklerin Avrupa'da doğalolarak yayılış gösteren Kitaibela vitifolia olduğuna karar verildi ve yeniden betimlendi. Ayrıca,türün coğrafik dağılımı haritalandı ve IUCN tehlike kategorisi tartışıldı.In this study, Kitaibela vitifolia Willd. was recorded at the first time for Flora of Turkey. This species is a natural, narrow-spread endemic in the Former Yugoslavia and Albania, and is cultural in Hungary and Romania. This species was observed in pine forest openings during the field studies carried out within the scope of the biodiversity project in the Amanos Mountains (Osmaniye) and the samples were photographed. These samples were collected to make the herbarium material. After checking Flora of Turkey and associated flora books, it was decided that these examples was Kitaibela vitifolia naturally distributed in Europe and it was described again. In addition, the geographical distribution of the species was mapped and the IUCN threat category was discussed