Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2025The effect of high SiC ratio on the physical, mechanical, tribological and corrosion behavior of Al2024 alloy matrix composites fabricated by powder metallurgy
Beder, Murat; Varol, Temel; Akçay, Serhatcan Berk; Çuvalcı, Hamdullah; Erdemir, Fatih; Khan, M Adam; Yıldız, Uğur Temel
Reinforcing materials used in the production of metal matrix composites are used to improve the properties of the final composite. However, the compatibility between matrix and reinforcement and the reinforcement ratio directly affects the properties of the composite material. For this reason, low reinforcement ratios are preferred in many studies on ceramic particle reinforced composites. Unlike conventional studies, in this study, the effects of 10 wt%, 20 wt% and 40 wt% SiC content on the microstructure, dry wear properties and corrosion properties of Al2024 matrix composites were investigated. θ phase content became higher as the SiC content was increased. Hardness values increased with increasing SiC reinforcement. The highest value (307.68 HB) was obtained for the composite with 40 wt% SiC reinforcement, an increase of more than 100%. A decrease in volume loss with increasing SiC reinforcement was observed in the friction and wear tests. For 5 N of load and 1200 m of sliding distance, it was found that an addition of 40 wt% of SiC particles in Al2024 matrix results decrease in volume loss by almost 722%.
- MakaleYalnız künye2025Effect of mechanical milling parameters on the properties of electrolytic pure copper powders and hot pressed billets fabricated from recycled copper wastes
Akçay, Serhatcan Berk; Çuvalcı, Oğuzhan; Varol, Temel; Çuvalcı, Hamdullah; Kocaman, Mücahit; Alver, Ümit; Beder, Murat; Güler, Onur; Aksa, Hüseyin Can; Gasha, Shimelis Bihon
This study was conducted to comprehensively investigate the effect of mechanical milling parameters on the properties of electrolytic pure copper powders and hot pressed billets fabricated from recycled copper wastes. Three different milling speeds, five different milling times and three different ball to powder weight ratios were used to fully reveal the effect of the mechanical milling process on the properties of recovered Cu powders. The results show that as the milling time and milling speed increased, the initial dendritic morphology of the copper was transformed into a flake-like structure. At 400 rpm and a 5:1 BPR parameters, the average particle sizes of C3, C4, and C5 after 2, 4, and 8h were ∼52 μm, 83 μm, and 71 μm, respectively. This suggests that particle size initially increases due to shape change and cold-welding, but at longer durations, fracture becomes dominant. The I5 with d(0.5) = 69.32 μm exhibited a high flow rate of 5.88 g/s with an apparent density of 2.9 g/cm3.While the hardness value of the Cu samples (A1-bulk sample) produced by exposure to the lowest deformation during the mechanical milling is 95.02 HB, the hardness value of the Cu specimens (F5-bulk sample) showing the highest apparent density, best flow rate and highest density values is 109.31 HB. The electrical conductivity values were determined to be approximately 52.2 MS/m, 57.4 MS/m and 44.3 MS/m for A1-bulk, F5-bulk and H5-bulk, respectively. This study offers valuable insights into the relationship between milling parameters, powder characteristics, and final material properties.
- MakaleAçık Erişim2024The Effect of Heat Treatment on the Mechanical Properties and Oxidation Resistance of AlSi10Mg Alloy
Beder, Murat; Akçay, Serhatcan Berk; Varol, Temel; Çuvalcı, Hamdullah
In this study, the microstructure, hardness, tensile strength, and dry wear properties of the cast AlSi10Mg alloy as well as the effects of processing parameters on the oxidation behavior of this alloy were investigated. In this context, AlSi10Mg (wt%) alloy was produced by gravity die casting method, and then, air cooling, quenching, and T6 treatment were applied. The microstructure of the alloy was investigated using an optical microscope, SEM, and EDS. Additionally, thermogravimetric analysis (TGA) was used to determine the effect of processing parameters on the oxidation behavior of the samples. The friction and wear properties of the alloy were investigated using a ball-on-disk wear test device. It was founded that the as-cast AlSi10Mg alloy's microstructure contained phases of α(Al), Si, and β-Mg2Si. It has been observed that the microstructure of the cast AlSi10Mg alloy gradually turns into a spherical form when quenching and air-cooling heat treatments are applied. Also, T6 heat treatment led to further spheroidization of Si particles, formation of β-Mg2Si precipitates, and elimination of the Chinese script morphology of the β-Mg2Si phase. It was observed that the yield strength of the AlSi10Mg alloy in the as-cast state decreased negligibly compared to the air-cooled state, while there was an increase of up to 70% in the aging-treated condition. The results show that the tensile strength of the as-cast AlSi10Mg alloy increased by 115% after aging. Additionally, it was found that the AlSi10Mg alloy's wear resistance increased with the aging process.