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The present study aims to investigate the effect of reinforcing TiB2 particles on the properties of in situ synthesized Ti3SiC2. For this purpose, TiB2/Ti3SiC2 composites with 5, 10, and 15 wt%TiB2 addition were synthesized through spark plasma sintering. TiB2/Ti3SiC2 composites were fabricated by this technique for the first time and the effect of TiB2 addition was evaluated comprehensively in terms of sintering behavior and density, phase development, microstructure, mechanical, thermal, and wear properties. Fully densified TiB2/Ti3SiC2 composites without the formation of any impurity phases were obtained at 1300 °C, for 15 min, under a pressure of 50 MPa. The mechanical properties and thermal diffusivity of composites were increased with the increasing TiB2 content. The most significant effect of TiB2 addition was obtained in wear properties compared to Ti3SiC2 matrix.

This study presents the tribological behavior of epoxy matrix composites containing two different fillers. The composites contain fillers with different particle sizes (

Pure Al and alumina (2, 5, 10 wt.% Al2O3)-added Al composite foams were fabricated through powder metallurgy technique, where boric acid (H3BO3) is employed as a new alternative foaming agent. It is aimed to determine the effects of boric acid on the foaming behavior and cellular structure and also purposed to develop the mechanical properties of Al foams by addition of Al2O3. Al and Al composite foams with porosity fraction in the range of 46-53% were achieved by sintering at 620 °C for 2 h. Cell morphology was characterized using a combination of stereomicroscope equipped with image analyzer and scanning electron microscopy. Microhardness values were measured via using Vickers indentation technique. Quasi-static compression tests were performed at strain rate of 10−3 s−1. Compressive strength and energy absorption of the composite foams enhanced not only by the increasing weight fraction of alumina, but also by the usage of boric acid which leads to formation of boron oxide (B2O3) acting as a binder in obtaining dense cell walls. The results revealed that the boric acid has outstanding potential as foaming agent in the fabrication of Al and Al composite foams by providing improved mechanical properties.

Al2O3 composites, comprising 10 wt% ZrO2 stabilized with 0.3 wt% MgO (MSZ/Al2O3) and 17.5–25 vol% cubic boron nitride (cBN)-added MSZ/Al2O3, were fabricated by spark plasma sintering technique, and the wear behavior of these composites was evaluated in terms of friction, wear rates, and wear mechanisms by ball-on-disk contact with dry and rotational sliding at room temperature against two different counterparts. The coefficient of friction (CoF) was smaller when sliding against tungsten carbide counterpart than in comparison with that sliding against sapphire ball for both with or without cBN-added composites. While the wear was characterized by a combination of mild abrasion and adhesion wear in the form of micro-cracking, micro-fragmentation, generation, and spalling of the oxidative tribochemical layer for the MSZ/Al2O3 composites, the experimental results have shown that the dominating wear was generated by a third-body wear for cBN-added composites via extraction of hard cBN grains from the matrix and related to density and hardness of the composites against both counterpart materials.

Although there are several researches focused on the improvement of strength of metal based foams by adding ceramic particles, the investigations of the effect of cubic boron nitride (cBN) reinforcement on the mechanism or properties of Al foams are very limited so far. In this study, it is aimed to develop and investigate the properties of Al matrix by cBN addition in different amounts (2, 5, 10 wt%). cBN/pure Al composite foams were fabricated by using boric acid (H3BO3) as foaming agent with the mean size of 500 μm under compacting pressure of 150 bar and sintering temperature 620 °C for 3 h at Ar atmosphere. The theoretical densities of sintered composite foams with porosity fraction of 50 vol% were measured according to Archimedes method. The phase analyses were conducted employing an XRD. The microstructures were studied by stereomicroscope equipped with image analyser. Compression tests were performed at the strain rate of 10−3 s−1 for evaluating the compressive behaviour and energy absorpt...

The powder mixtures of Ti, Si, TiC and Al were sintered to synthesize Ti3SiC2 and Ti3SiC2/SiC by spark plasma sintering (SPS) method. Single phase Ti3SiC2 and Ti3SiC2/SiC composites were obtained by sintering Ti/1.1Si/2TiC/0.2Al and 2.2Si/3TiC/0.2Al at 1400 °C, for 15 min, under a pressure of 50 MPa, respectively. The reduction of Al and Si contents in the starting powder mixture led to the formation of TiC impurity phase. X-ray diffraction (XRD) and Rietveld analyses were used to evaluate the phase constituents. The main objective of this study was to reveal the properties of single phase Ti3SiC2 and to evaluate the development of the mechanical and tribological properties of Ti3SiC2/SiC comprehensively. The results indicated that the SiC in situ reinforced Ti3SiC2 composites exhibited higher hardness, fracture toughness and wear resistance compared to single phase Ti3SiC2.

The demand for utilization of boron wastes related to the generation of massive amounts in each year is on the rise. In order to meet this growing need and demand for fabrication of environmentally friendly products, epoxy matrix composites containing 60wt% of boron wastes was developed. The influence of boron waste addition and the particle size of boron waste on epoxy matrix composites on physico-mechanical and tribological properties were evaluated. It was found that, hardness, flexural modulus and wear resistance properties were increased with the incorporation of boron wastes. Wear resistance increased with increasing boron waste particle size. The lowest specific wear rate was achieved for the largest particle size added composites. The physico-mechanical properties as well as microstructure wear behavior correlation were evaluated comprehensively.