As a result of advances in science and technology, the importance of metal matrix composite materials is increasing gradually today. However, in many studies, composite production is carried out with monotype ceramic particle reinforcement. In this study, the production, microstructure-hardness, and wear performance of composite-hybrid materials that had AA 7075 aluminum powder metal matrix and were reinforced by SiC and Al2O3 ceramic particles at different ratios were examined. The prepared Matrix and reinforcement powder mixtures were mixed for half an hour in the three-axis Turbula T2F type mixer and then, pressed unidirectionally and cylindrically under the pressure of 700 MPa. The pressed samples were sintered for 1 h at a temperature of 600oC in the argon atmosphere. Microstructure examinations were carried out using SEM (Scanning Electron Microscope) and optical microscope devices, while hardness measurements were obtained as a result of Brinell measurement. Wear performance of the test samples were tested in the Pin-on-disk type device at 10 N load and 500 rpm rotation speed by depending on the wear distances at 1000, 1500 and 2000 m. It was observed that hardness increased as the amount of ceramic particle in composite-hybrid samples increased. As a result of wear tests, in hybrid composites, compared to single-phase ceramic particle reinforced composites, weight losses increased depending on the increase in the reinforcement amount.

Al₂O₃/B₄C ceramic phase composite structure was produced by solid-state method. Transformations of ceramic phases, micromorphology were determined by employing X-ray diffraction, FT-IR, scanning electron microscopy and transmission electron microscopy (TEM). Transformation of ceramic phases was completed in a short time (6 h). Formation of Al₂O₃/B₄C ceramic-phase powder mixtures was specified after leaching. As a result of the increase of mechanical energy and the amount of ceramic phase, reduction in powder particle size (50–350 nm) and increase in agglomeration tendency were observed. The impurities were removed after leaching and the distribution in which the ceramic phases are effective was obtained with the TEM study.

Kömür küllerinin geri dönüşümü olmadığı için doğaya atılması ciddi zararlar ortaya çıkarmaktadır. Aynı zamanda kömür külünün kimyasal bileşiminde insan ve hayvan sağlığına zararlı maddelerin olması özellikle doğal yağışlar sayesinde içme sularına karışması canlıların ve sulama yapılan tarım alanlarını ciddi şekilde tehlikeye sokmaktadır. Türkiye’de birçok termik santral bulunmaktadır. Buralardan elde edilen atıkların geri dönüştürülmesi ve ekonomiye kazandırılması büyük önem arz etmektedir. Endüstriyel atıkların polimer teknolojisi sektöründe dolgu olarak kullanılmasıyla ilgili sınırlı sayıda çalışmalar mevcuttur. Kömür külünün polimer matrisli bileşiklerde kullanılması ile ilgili hiçbir çalışma mevcut değildir. Bu çalışmada SBR matrisine %0, %5, %10 ve %15 oranında karbon siyahına ek olarak kömür külü ilave edilmiş ve 4 farklı bileşik elde dilmiştir. Elde edilen bu bileşiklerin çapraz bağ yoğunluğu hesaplanmış ve çapraz bağ yoğunluğunun mekanik özellikler üzerine etkisi araştırılmıştır. Bileşiklerdeki kömür külü dolgu oranı yükseldikçe, bileşiklerin çapraz bağ yoğunluğunun artmasına ve buna bağlı olarak, sertlik, yüzde uzama, kopma mukavemeti gibi mekanik özellikleri geliştirdiği ve özgül ağırlık gibi fiziksel özelikleri de arttırdığı görülmüştür.

In this study, nanoparticle boron carbide was produced after the reduction of boron oxide with magnesium under the presence of carbon by using mechanochemical synthesis method. During the synthesis processing, microstructure and phase transformations of powders were performed by using X-ray diffraction (XRD), Fourier-transform infrared spectrum (FT-IR), scanning electron microscope (SEM), and high-resolution transmission electron microscopy (HRTEM). At the end of 2 h, reaction products (MgO, B₄C) were determined by XRD and FT-IR examinations. Nanoparticle B₄C single-phase crystalline structure from the MgO/B₄C composite powder mixture, which was the reaction product, was obtained by leaching process. With the increase in the synthesis period, starting material peaks diminished and Fe peak intensity became evident. After the HRTEM examinations, it was determined that synthesized B₄C particles were within range of 10–200 nm especially in the activation of leaching process. Additionally, by using spot pattern analysis method, planes represented by B₄C particles were calculated.

In this study, using AA 2014 aluminum alloy, AA2014/wollastanite, AA2014/wood ash, and AA2014/wollastanite/wood ash composite hybrid materials were produced by powder metallurgy method. The powders, whose mixing ratios were determined by weight, were mixed in a 3-dimensional mixer for 30 min. The prepared mixture powders were pressed uniformly under a pressure of 700 MPa, and cylindrical materials with a diameter of 10 mm were obtained. Then, the materials were sintered for 1 h under argon gas flow at a temperature of 600°C. The density, microstructure, hardness, and wear behavior of the materials were examined. It was observed that the density of the composite materials increased relatively compared to AA 2014 alloy. As the particle reinforcement ratios increased, porosity amounts also increased in the composite and especially in the hybrid materials. In the wood ash-reinforced composite materials, the particles were distributed more homogeneously in the microstructure. The highest hardness value obtained was 70.65 HV in AA2014/15% wollastanite composite material. The weight loss increased in the materials created by particle reinforcement, and the lowest weight loss (170 mg) was determined in this material.