SEARCH RESULT

Copper, which is known to have very good electrical and thermal conductivity, has poor mechanical properties. In order to overcome this negativity, the production of coppermatrix composites is becoming increasingly popular. In this study, copper (Cu) matrix ferrochromium (FeCr) and ferroboron (FeB) reinforced composites were produced. Cold pressing and sintering process were preferred as production methods. Microstructure and phase composition of the composites were examined by using scanning electron microscope (SEM). Hardness properties were carried out microhardness device. Also, Densities of composites were studied. SEM images showed that FeCr and FeB reinforcements were partially homogeneously dispersed in the Cu matrix. In the presence of FeCr and FeB in the Cu matrix, the hardness of the Cu matrix was considerably increased.

International Iron & Steel Symposium
UDCS

Mehmet Akkaş Serkan Islak Uğur Çalıgülü Mustafa Boz

In this study, GR2 and GR5 alloys among Ti alloys which have increasingly more usage areas in the metalmaterial industry were joined by diffusion welding method using a copper interlayer. The diffusion temperature was selected as a variable parameter during the diffusion welding process and the effects of the welding temperature on the joint quality were examined. Diffusion welds were made by applying a pressure of 5 MPa at 950 and 980 °C to the samples prepared in Ø12 x 12 mm dimensions in specially prepared diffusion welding apparatus and sending argon gas with a purity of 99.9% at a flow rate of 5 lt/min into a furnace with silicon carbide rod. Welding process was carried out to the experimental samples for 55 minutes. The samples were kept in the furnace until the furnace’s temperature decreased to 250 oC and then they were kept to cool down at room temperature. Microstructure analyses were then performed by using an optical microscope and microhardness analysis was performed on each sample. As a result of the study, it was found that as the temperature of diffusion welding increased, the better welded joints were obtained in the samples and their microhardness values also increased.

International Iron & Steel Symposium
UDCS

Haluk KEJANLI Nida KATI Uğur Çalıgülü

In this study, the results of joining of P460 steel combined with a submerged arc welding (SAW) weld by X-Ray radiographic test were investigated. P460 material pairs were welded at different welding speed and ampere values using the submerged arc welding method. These welded samples are; Notch impact test, microhardness measurement, X-ray diffraction method and radiography tests were examined. Microstructural changes occurring in the weld zone of weld parameters after welding; by optical microscopy and EDS analysis were investigated. As a result of the experiments, it has been found that the P460 steel show the ability to weld sufficiently strong by the submerged welding method.

International Iron & Steel Symposium
UDCS

Uğur Çalıgülü Mustafa Turkmen Ebru Tufanoglu Sermin Ozan

In this study, Cu–Mo composite coatings were produced on copper substrate by plasma spray technique. Electrical conductivity and microstructure properties of the composite coatings were investigated. Microstructure and phase composition of the coatings were examined by using optical microscopy (OM), scanning electron microscope (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). The microhardness experiments were also performed by using a microhardness machine. The electrical conductivity properties of the coatings were evaluated with eddy current instruments. Although the electrical conductivities of the coatings are very small compared to the substrate, it has been determined that the coatings exhibit a very good hardness values in comparison to the substrate.

International Symposium on Light Alloys and Composite Materials
UHAKS

Serkan Islak Uğur Çalıgülü Husain R.H. Hraam Cihan Özorak Vahdettin Koç