Development of Hot Equal Channel Angular Processing (ECAP) consolidation technique in the production of Boron Carbide(B4C)-Reinforced Aluminium Chip (AA6061)-based composite

The production of metal matrix composites (MMCs) through recycled materials is a cost-saving process. However, the improvement of the mechanical and physical properties is another challenge to be concerned. In this study, recycled aluminium 6061 (AA6061) chips reinforced with different volumetric fractions of boron carbide (B4C) were produced through hot equal channel angular processing (ECAP). Response surface methodology (RSM) was carried out to investigate the dependent response (compressive strength) with independent parameters such as different volumetric fractions (5-15%) of added contents of B4C and preheating temperature (450 – 550°C). Also, the number of passes were examined to check the effect on the mechanical and physical properties of the developed recycled AA6061/B4C composite. The results show that maximum compressive strength and hardness of recycled AA6061/B4C were 59.2 MPa and 69 HV respectively at 5% of B4C contents. Likewise, the density and number of pores increased, which were confirmed through scanning electron microscope (SEM) and atomic force microscopes (AFM) analysis. However, the number of passes enhanced the mechanical and physical properties of the recycled AA6061/B4C composite. Therefore, the maximum compressive strength and hardness achieved were 158 MPa and 74.95 HV for the 4th pass. Moreover, the physical properties of recycled AA6061/B4C composite become denser of 2.62 g/cm3 at the 1st pass and 2.67 g/cm3 for the 4th pass. Thus, it can be concluded that the B4C volumetric fraction and number of passes have a significant effect on recycled AA6061 chips

Localizatation estimation usign the technique of multi-sequence positioning

Wireless sensor networks (WSN) have been considered as promising tools for many location dependent applications such as area surveillance, search and rescue, mobile tracking and navigation, etc. In addition, the geographic information of sensor nodes can be critical for improving network management, topology planning, packet routing and security. Although localization plays an important role in all those systems, itself is a challenging problem due to extremely limited resources available at each low-cost sensor node. This study is focusing on using a distribution-based estimation method. The reason for selecting this method because it is considered an energy saving effort comparing to costly centralized localization scheme. The scope of the estimation in localization of sensor nodes is a Multi-Sequence Positioning (MSP) method that can be applied for a large-scale network in order to achieve accurate distance estimation in sensor deployments where the source of event has a line-of-sight to all sensors. The MATLAB is the programming will be used in the study. This is conceived as an extension of existing WSN programming frameworks. The evaluation was carried based on the error resulted from location estimation scenario compared to the current localization technique of Received Signal Strength (RSS) and the Time of Arrival (TOA). The result showed that MSP showed more efficiently in short and long range as compared to TOA. However, RSS proven to perform better than MSP in long range estimation. This was reasoned to different functional related measures in which RSS is usually perceive less obstruction and shielding of satellite signals whereas MSP can be effected by cellular networks in which it limited by the cell size

AA7075-ZrO2 Nanocomposites Produced by the Consecutive Solid-State Process: A Review of Characterisation and Potential Applications

Solid-state recycling is a direct conversion method for producing metal chips, whereas the materials are plastically deformed into the final product without melting, offering lower energy consumption and metal waste. This technique was reported for fabricating aluminium-zirconium oxide (Al-ZrO2) composite and it was widely used to avoid metal chips bounding at high temperatures during the extrusion process. Aluminium alloy (AA7075) is known for its high yield strength of more than 500 MPa under optimum ageing conditions. However, AA7075 can be further reinforced by zirconium oxide nanoparticles when needed for high-performance applications. Hot extrusion is used to obtain better mechanical properties of composite materials. The equal channel angular pressing (ECAP), a severe plastic deformation technique, was recently used to produce bulk and light recycled metal chips, such as porosity-free and ultra-fine-grained aluminium nanocomposites (ANCs). Heat treatments (HT) and ECAP post hot extrusion are mostly incorporated to improve tribological and mechanical properties and aluminium nanocomposite bonding efficiency. In this review, ANCs’ fabrication by the hot extrusion technique and the effects of ZrO2 nanoparticle are duly summarised and discussed. Furthermore, this review emphasises the importance of using HT and ECAP techniques to acquire better metal alloy incorporation, such as AA7075-ZrO2. Interestingly, owing to the lightweight properties and superior performance of AA7075-ZrO2, it was reported to be suitable for fabricating many drones’ parts, military equipment, and some other promising applications

Effects of Preheating Temperature on Deformed AA6061 Aluminium Properties of Hot Equal Channel Angular Pressing (ECAP) by Using Deform-3D Software

In this paper, the deformation characteristics of engineering AA6061 aluminium in the Equal Channel Angular Pressing (ECAP) are performed using the deformed 3D software. This study is designed to use 0.01 friction, 80,000 number of elements, and 450C, 500C, 550C preheating temperature. The study investigates the effects of die factors such as ECAP outer or inner ingles, die displacement, strength coefficient applied punch force, strain homogeneity, and strain distribution. Moreover, the hot ECAP die factors have played an essential role in the magnitude of material effective strain. On the one hand, decreasing die angles leads to imposing more strain with higher punch force on the workpiece, which results in more homogeneity of the processed materials. On the other hand, stress distribution mainly occurs at the die corner of the die, raising the temperature gradient. In comparison mechanical and physical properties which show an important agreement to support the importance of temperature processing gradient investigations. The study confirms that preheating temperature and friction values play a significant role in hot ECAP materials forming and die safety

Effects of Preheating Temperature on Deformed AA6061 Aluminium Properties of Hot Equal Channel Angular Pressing (ECAP) by Using Deform-3D Software

In this paper, the deformation characteristics of engineering AA6061 aluminium in the Equal Channel Angular Pressing (ECAP) are performed using the deformed 3D software. This study is designed to use 0.01 friction, 80,000 number of elements, and 450C, 500C, 550C preheating temperature. The study investigates the effects of die factors such as ECAP outer or inner ingles, die displacement, strength coefficient applied punch force, strain homogeneity, and strain distribution. Moreover, the hot ECAP die factors have played an essential role in the magnitude of material effective strain. On the one hand, decreasing die angles leads to imposing more strain with higher punch force on the workpiece, which results in more homogeneity of the processed materials. On the other hand, stress distribution mainly occurs at the die corner of the die, raising the temperature gradient. In comparison mechanical and physical properties which show an important agreement to support the importance of temperature processing gradient investigations. The study confirms that preheating temperature and friction values play a significant role in hot ECAP materials forming and die safety