Search

Bimodal size SiC particles reinforced Al-Si alloy composites were fabricated by powder metallurgy route. Three different bimodal reinforcements with various volume fractions of micro and nano sized SiC particles were dispersed in Al-11.5%Si-1%Mg matrix by mechanical alloying for 10 h. The composite powders were hot pressed at 580 °C, 600 °C and 620 °C in a vacuum atmosphere with different cooling rates (10 °C/min, 15 °C/min and 20 °C/min). The microstructural changes of bimodal SiC(m–n) in the matrix material were carried out using OM, SEM and TEM with energy dispersive spectroscopy (EDS). The sample experiments were implemented based on Taguchi L9 OA with three parameters of bimodal reinforcement, sintering temperature and rate of cooling respectively. The measurement of mechanical properties specifies that hardness and tensile strength of Al-11.5%Si-1%Mg composite increases with the decrease of nano-SiC concentration in bimodal reinforcement. Moreover, the fine precipitation of Al-Si rich compound as observed at higher cooling rate (20 °C/min) also contributed for the strength improvement of developing composite. [ABSTRACT FROM AUTHOR]

Drilling process plays a vital role in the development of polymer clay nanocomposites. The effects of various parameters, such as tool, feed rate and speed to generate the impact on tangential force, thrust force and delamination factor acting on the material in production are studied during drilling operations in the aerospace and automotive industries. The input variable settings to adjust the speed and feed rate to show the outcomes of tangential force, thrust force and delamination factor of the material according to the consumption of the parts in the next stage of manufacturing are calculated by efficient feed rate optimization. A series of tests are performed by changing tools such as High speed steel (HSS), end mill (HEM), High speed steel (HSS), twist drill (HTD) and carbide twist drill (CTD) on various materials to evaluate the influence on the feed rate and speed. Based on the experimental analysis, mathematical modeling is implemented to study the properties of glass fiber reinforced polyester nanocomposite (GFRPNC; 3 wt.%). Using the desirability approach, the optimum operating conditions of the selected process variables are considered to minimize delamination. A full factorial experiment design is adopted using the two fundamental concepts of replication and randomization of experimental design to research the relationship between the variables. Based on the analysis of variance (ANOVA), the process model is formulated using the Minitab ® statistical kit. It is inferred that the delamination factor is minimal for all tools (CTD, HTD and HEM) at 0.1 mm/rev feed rate and speed at 852 rpm. [ABSTRACT FROM AUTHOR]