Abstract. High-energy mechanical alloying method was used to prepare Al-12Si-xZrC (x = 0, 5, 10, 15 wt. %) nanocomposites. Cylindrical preforms were prepared with an initial preform density of 89% by using a suitable die and punch assembly. The preforms were sintered in a muffle furnace with an inert gas atmosphere at a temperature of 550°C, followed by cooling until room temperature has been attained. Scanning electron microscope (SEM) and X-ray diffraction (XRD) techniques were used to characterize the composites. Pin-on-disc wear testing machine was used to determine the tribological properties of the prepared composites. The results show that the wear loss reduced with increasing the reinforcement content and coefficient of friction increases gradually. Normally, solid state methods are used to produce composites with high mechanical properties, because these methods deliver a uniform distribution of reinforcing phase particle in the matrix material [6][7][8][9][10]. Some trials were conducted to fabricate Al-12Si-xZrC nanocomposites using different techniques, but the mechanical alloying method is a suitable technique to fabricate Al-12Si-xZrC nanocomposites. No attempt has been made to fabricate Al matrix composites reinforced with ZrC particles using the P/M method. In this present paper, an effort is made to study the outcome of wear behavior of Al-12Si-xZrC nanocomposites prepared with the mechanical alloying method. These composites were characterized using SEM and XRD. The wear behavior was calculated using the weight loss method. The worn surfaces and wear debris were characterized using SEM. Experimental procedure2.1. Materials. Aluminium and silicon with 99.5% purity and particle size of 44 µm were purchased from Metal Powder Company Limited, Thirumangalam, Tamilnadu, India, and the ZrC powder with a high, 99.9% purity and particle size of 400 nm was purchased from US Research Nanomaterials, Inc., USA. The individual powders were pulverized and mixed in a high-energy ball mill with ball-to-powder weight ratio of 20:1. The milling was done at a constant speed of 300 rpm in a wet medium with a presence of toluene to avoid oxidation and agglomeration. Scanning electron microscope images were used for the analysis of mixed powder particles. Fig. 1 shows the received powders of aluminium, silicon, and zirconium carbide. From the SEM images, it can be visualized that aluminium was spherical in shape, silicon was flattened and nano-zirconium carbide had a cubic crystal shape.

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Excellent mechanical properties and corrosion resistance combined with low weight qualify b-titanium materials for lightweight applications in aviation, automotive and energy engineering. Thus far, actual applications of these materials have been limited due to high material costs and limited processing knowledge. One approach for developing resource-efficient manufacturing methods is the application of incremental forming methods. This article focuses on the development of the incremental spin extrusion process, which creates hollow profiles from solid bars. This method allows hollow shape manufacturing with a much higher flexibility than other forming methods and a significantly improved material utilization in comparison to machining methods, such as deep hole drilling. Beta-titanium alloys basically have very good cold forming suitability and the resulting material properties can be controlled. The application of incremental forming methods with high hydrostatic compressive stress is a promising manufacturing approach. The b-titanium Ti-10V-2Fe-3Al material has an excellent combination of the properties strength, ductility and fatigue strength. In order to utilize these properties the forming conditions and the temperature control need to be optimized. The investigations show that the Ti-10V-2Fe-3Al material can be formed only in a narrow semi-hot forming temperature window. The paper describes the investigation and presents results on the design of partial forming process sequences, forming properties, microstructure formation and failure prevention. The process design objective is a very fine microstructure with a homogeneous secondary a-phase and very small grained b-phase.