G.B. Bhaskar

Influence of Graphite Reinforcement on Mechanical Properties of Aluminum-Boron Carbide Composites

This paper deals with the mechanical properties in conventional heat treatment of Al (6061)-B4C-Graphite. Aluminium Metal Matrix Composites (MMC) is fabricated through two step stir casting method. The composites were fabricated with various volume percentage levels as Aluminium reinforced with (5, 10 &15%) Boron Carbide and (5,10 & 15%) of Graphite. Fabricated composites were subjected to conventional heat treatment for enhancing the mechanical properties. Influences of Graphite reinforcement on mechanical properties of Aluminum-Boron carbide composites were analyzed. The microstructure studies were also carried out. It is observed that increasing the graphite content within the aluminum matrix results in significant decrease in ductility, hardness, ultimate tensile strength. The addition of boron carbide conversely increased the hardness of the composites.

Flexural Analysis on GFRP Composites Subjected to Cyclic Gradual Load and Cyclic Impact

Glass fiber reinforced polymeric (GFRP) composite laminates have been prepared by hand layup method. According to ASTM standard, the test specimens have been prepared to carry out the flexural bending tests. The specimens have been subjected to both cyclic impact load and cyclic gradual load with various frequencies prior to the flexural bending analysis. Three point bend method has been adopted to find out the flexural strength and flexural modulus. Flexural strength and modulus have been calculated from the load deflection curve obtained from the tensometer for respective specimens. The flexural bending properties of GFRP composites subjected to cyclic gradual load and cyclic impact have been compared and found that the GFRP composite materials are effective for gradual cyclic load than the cyclic impact load.

Influence of SMA reinforcement on the impact resistance of GFRP composite laminates under different temperatures

Plain glass fibre-reinforced polymeric (GFRP) laminates and GFRP reinforced with randomly oriented short strips of shape memory alloy (SMA) were prepared by hand lay-up method. The SMA strip reinforcement was placed at 0.75 × thickness of the laminate with weight fractions of 2, 4 and 6%. The specimens were exposed to drop weight impact test and the experiments were conducted at a constant impact velocity of 2.80 m s−1 with different test temperatures such as 303, 333 and 363 K. The impact damage area was evaluated using lighting technique and fracture response was analysed using scanning electron microscopic (SEM) images. Absorption of impact energy and damage area due to low velocity impact were calculated. It was observed that with the higher temperature, the SMA/GFRP laminates exhibit marginally-enhanced damage resistance compared to the plain GFRP laminates. Also, addition of SMA reinforcement was not contributing much to the impact resistance at higher temperature.

Corrosion Behavior of Aluminium-Boron Carbide-Graphite Composites

The corrosion behaviour of Al (6061)-B4C-Graphite was investigated. The Aluminium Metal Matrix Composites (AMMC) was fabricated through two step stir casting method. The composites were fabricated with various volume percentages of Boron Carbide (5, 10 &15%) and Graphite (5, 10& 15%). Corrosion studies of AMMC was investigated with 4%, 8%, 12% wt. % NaCl solution at room temperature. Also erosion-corrosion test were performed on the specimens in the NaCl solution with silica sand. Erosion-corrosion tests indicated that the rate of material loss mechanism is mechanical abrasion with enhanced corrosion. The material loss mechanism was significantly higher in the case of erosion-corrosion tests.

Effect of process parameters on physical measurements of AISI316 stainless steel coating on EN24 in friction surfacing

ABSTRACT An investigation was successfully made in the present work to obtain the solid-state coating of AISI316 stainless steel over EN24 medium carbon steel by friction surfacing process. Spindle speed, axial force, and table traverse speed were perceived to be the supreme aspects for bonding integrity. It was observed that the depth of the coating (Ct) lessened as the coating width (Cw) increased. The impact of process parameters on physical geometry of the coating was explored by experimentation based on desirability approach. The coefficients of correlation for coating width (0.94) and thickness (0.99) are extremely high. The coatings exhibited martensitic microstructure with fine grain size and without carbide particles which substantiates the effectiveness of good bonding. The optimal process parameters were identified by response surface methodology as 2.26u2009mm/s of Ts, 7.20u2009kN of AL, and 1447.17u2009rpm of RoS and also the output values are observed as Ctu2009=u20092.10u2009mm and CWu2009=u200917.21u2009mm.

Multi Response DEA-Based Taguchi Optimization of Process Parameters on AA8011 Friction Stir Welded Aluminium Alloys

In this investigation, an attempt using data envelopment analysis based Taguchi method, is involved in solving the multi-response optimization of the process parameters of rotational speed, transverse speed, tool tilt angle with different tool pin profiles on the stir zone evolution in AA8011 Aluminium alloys. Three different tool pin profiles (hexagonal, pentagonal pin profiles of High Carbon High Chromium steel and Hexagonal tool pin profile of H13 steel) have been used to make the joints at the different combination of process parameters using L9 orthogonal array. The Vickers hardness and Impact strength are measured to optimize the process parameters using DEA based Taguchi method. It is found that the optimum conditions of rotational speed 660 RPM, transverse speed of 30 mm per minute and tilt angle of 2 degrees with the hexagonal tool pin profile of High Carbon High Chromium steel yielded a good quality weld.

Dynamic Mechanical and Flexural Characteristics of Glass-Carbon Hybrid Composites

This paper deals with the fabrication of test specimens of Glass fiber reinforced plastic (GFRP), Carbon fiber reinforced plastic (CFRP), Glass-Carbon fiber reinforced plastic (G-CFRP) and Carbon glass fiber reinforced plastic (C-GFRP) by using hand layup method. The low velocity point load setup was fabricated and fixed in the milling machine by using cam pointer arrangement. The specimens have been subjected to the low velocity point load for specific duration by exposure time such as 0,15,30,45 and 60 minutes. Then impact and DMA tests are also carried out for the above specimens. From the DMA test results it was found that the storage modulus and loss factor of GFRP specimen are high compared with others. Izod impact test result shows that impact strength of G-CFRP specimen is high. The flexural results reveals that among the four types of laminates CFRP gives higher order of flexural strength and modulus compared to the others

Influence of SMA Short Fibers on Mechanical Properties of Copper/GFRP Composites

Plain GFRP, copper wire embedded GFRP and SMA short fibres included copper wires embedded GFRP laminates have been prepared by hand lay-up method. The mechanical properties like flexural and tensile strength were investigated. To study the impact properties of the laminates an experimental set up was designed and the impact strength of the laminates was studied by drop weight method. Three point bend method was adopted for flexural studies and the tensile strength was found by Instron Machine. It is found that the inclusion of SMA short fibres significantly improved the mechanical properties of the composites.

Response of Composite Leaf Springs to Low Velocity Impact Loading

Leaf springs are the traditional suspension elements, occupying a vital position in the automobile industry. This paper deals us the replacement of existing steel leaf spring by composite leaf spring. The dimensions of existing middle steel leaf spring of commercial vehicle (Tata ace mini truck) were taken and fabricated using a specially designed die. Single leaf of the suspension springs, each made up composite with bidirectional carbon fiber reinforced plastic (CFRP), bidirectional glass fiber reinforced plastic (GFRP) and hybrid glass-carbon fiber reinforced plastic (G-CFRP), was fabricated by hand layup process. It is to be mentioned here that the cross sectional area of the composite spring same as the metallic spring. A low velocity impact test rig was fabricated in the laboratory with loading set up. The composite leaf springs were tested with the low velocity impact test rig. By using the low velocity impact test rig, the deflection due to various drop height were measured.

Controlling of Faulty Vehicles Using GSM and GPS Technology

In the developing countries, the identification of Faulty Vehicle’s by the enforcing authorities within a stipulated time is a challenging task. Hit and run accident vehicles, traffic-rule violators, theft vehicles, escaping an accused in a vehicle and nonpayment of tax vehicles etc., are called as faulty vehicles. In the existing Intelligent Transportation System (ITS), only the vehicles are being monitored, instead of catching the faulty vehicle. In this methodology, the vehicles are controlled from the control room itself within stipulated time duration by controlling the fuel mixture. The concept involves minimization or stoppage of fuel mixture to that particular vehicle (three-wheeler Auto and four-wheeler Maruthi 800), depending upon its location (GPS) and the traffic environment; by using the specially designed electronic control unit (ECU) and with the help of a network provider (GSM). The entire concept is explained in this paper with the help of block diagram and photographs. From this investigation it’s observed that the vehicle could be stopped and it can be caught by the enforcing authority for necessary action.