A foot bracket is a metal panel bracket used to mount and support the footrest in two-wheeler systems. It holds the footrest in place while rigidly supporting it. In working conditions, this element has often been observed to fail when specific load-fluctuation conditions are established at its rear end. Appropriate materials therefore need to be identified to overcome such a recurring failure. To address these issues, the present study has been implemented with the specific objective to determine the response of selected Al6061-T6 and Al7075-T6 Hybrid Metal Matrix Composites (HMMC). The results, obtained using the ANSYS Software, show that the selected composites can withstand 636,962 N/m² of maximum stress and 8.88 × 10^{−6} m of minimum displacement. These results are also compared with relevant mathematical models and it is concluded that the identified material combination provides the required improvement of structural stability that can withstand the load fluctuation on the foot bracket.

Growing urbanization and industrialization triggered the population mobility from rural to urban and in the suburban. Lack of adequate public transport, people increasingly preferred to use individualized transport like two-wheeler motorcycles. Presently, the foot bracket in the two-wheeler motorcycle is made up of Al 6061-T6. It is observed that composite material foot bracket was subjected to fracture while the increases in the load at the rear end. It leads to frequent failure of the foot bracket. Considering the importance of this problem, Agostoni et al. [

Aboelseoud et al. [

Golushko [

Hence, SiC, TiC, Zn and Gr are chosen as reinforcement particles for enhancing the properties of Al 6061-T6 Alloy. These particles are added to the existing material with different volume fractions. In the case of the latter one, Al6061-T5 is completely replaced by Al7075-T6 alloy with the addition of the same volume fraction of reinforcement particles. Since the combinations of metal matrix and reinforcement particles are many, it is decided to use ANSYS software to simulate all the combinations and to sort out the appropriate combination for further evaluation of foot brackets.

In order to achieve more strength along with less weight, Al6061-T6 and Al7075-T6 have been chosen as matrix material. These matrix materials contain alloying elements that mainly contribute to improving the mechanical properties through the effects of Zn, Cr, and Ti. The chemical composition of Al6061-T6 and Al7075-T6 is presented in

Material | Zn | Mg | Cu | Si | Mn | Fe | Cr | Ti | Al |
---|---|---|---|---|---|---|---|---|---|

Al6061-T6 | Max 0.25 | 0.8–1.2 | 0.15–0.40 | 0.4–0.8 | Max 0.15 | Max 0.7 | 0.04–0.35 | Max 0.15 | Rem |

Al7075-T6 | 5.1–6.1 | 2.1–2.9 | 1.2–2.0 | 0.4 | 0.3 | 0.5 | 0.18–0.28 | 0.20 | Rem |

The existing model of the foot bracket in a two-wheeler is shown in

Material properties | Al6061-T6 | Al7075-T6 |
---|---|---|

Young’s modulus (N/m²) | 68.9 × 10^{9} |
71.7 × 10^{9} |

Density (kg/m³) | 2700 | 2810 |

Poisson’s ratio | 0.33 | 0.33 |

The addition of reinforcing material to the matrix can increase machinability, toughness, and hardness. As reinforcement materials, silicon carbide, titanium carbide, zinc, and graphite particles were chosen. Hybrid MMC refers to the layer-by-layer incorporation of these components into the matrix material. The properties of the reinforcement materials are shown in

Material properties | Silicon carbide | Titanium carbide | Zinc | Graphite |
---|---|---|---|---|

Young’s modulus (N/m²) | 90 × 10^{9} |
497 × 10^{9} |
97 × 10^{9} |
15.85 × 10^{9} |

Density (kg/m³) | 3100 | 4900 | 7100 | 2160 |

Poisson’s ratio | 0.14 | 0.187 | 0.25 | 0.20 |

The hybrid composite material properties such as Young’s modulus, density, and Poisson ratio have been calculated by considering the material properties and contribution of volume percentage of reinforcement particles and matrix materials. The formulae for the calculation of hybrid composite material properties are presented in

where, E_{m} = Young’s Modulus of Matrix; E_{r} = Young’s Modulus of Reinforcement; V_{m} = Volume of matrix; V_{r} = Volume of Reinforcement. The calculated material properties for derived hybrid composite is listed below in

Sl. No. | Composite | Young’s modulus(N/m²) | Density(kg/m³) | Poisson’sratio |
---|---|---|---|---|

1. | (a) 85%Al6061-T6+8%SiC+7%TiC | 100.555 × 10^{9} |
2886 | 0.305 |

(b) 85%Al6061-T6+10%SiC+5%TiC | 92.415 × 10^{9} |
2850 | 0.304 | |

(c) 85%Al6061-T6+12%SiC+3%TiC | 84.275 × 10^{9} |
2814 | 0.303 | |

2. | (a) 85%Al6061-T6+8%SiC+7%Zn | 72.555 × 10^{9} |
3040 | 0.309 |

(b) 85%Al6061-T6+10%SiC+5%Zn | 72.415 × 10^{9} |
2960 | 0.307 | |

(c) 85%Al6061-T6+12%SiC+3%Zn | 72.275 × 10^{9} |
2880 | 0.305 | |

3. | (a) 85%Al6061-T6+8%SiC+7%Gr | 66.876 × 10^{9} |
2694.2 | 0.306 |

(b) 85%Al6061-T6+10%SiC+5%Gr | 68.358 × 10^{9} |
2713 | 0.305 | |

(c) 85%Al6061-T6+12%SiC+3%Gr | 69.841 × 10^{9} |
2731.8 | 0.303 | |

4. | (a) 85%Al7075-T6+8%SiC+7%TiC | 102.935 × 10^{9} |
2979.5 | 0.305 |

(b) 85%Al7075-T6+10%SiC+5%TiC | 94.795 × 10^{9} |
2943.5 | 0.304 | |

(c) 85%Al7075-T6+12%SiC+3%TiC | 86.655 × 10^{9} |
2907.5 | 0.303 | |

5. | (a) 85%Al7075-T6+8% SiC+7%Zn | 74.935 × 10^{9} |
3133.5 | 0.309 |

(b) 85%Al7075-T6+10%SiC+5%Zn | 74.795 × 10^{9} |
3053.5 | 0.307 | |

(c) 85%Al7075-T6+12%SiC+3%Zn | 74.655 × 10^{9} |
2973.5 | 0.305 | |

6. | (a) 85%Al7075-T6+8%SiC+7%Gr | 69.255 × 10^{9} |
2787.7 | 0.306 |

(b) 85%Al7075-T6+10%SiC+5%Gr | 70.738 × 10^{9} |
2806.5 | 0.305 | |

(c) 85%Al7075-T6+12%SiC+3%Gr | 72.221 × 10^{9} |
2825.3 | 0.303 |

The failure analysis was performed on the foot bracket of the “Yamaha Libero G5” two-wheeler, which is made of Aluminum alloy 6061 and was cracked owing to abrupt load changes during driving. As a result, we’ve taken this Al6061 as an existing material that can be cast again with the addition of SiC, TiC, and Zn reinforcements. In addition, Al7075, which is rich in titanium, can be used as a substitute for Al6061. The inclusion of Si and Ti carbides resulted in remarkable recrystallization material structure, toughness, and hardness, among other properties. Through solid solution strengthening, the addition of Mg to Al7075 has progressed good strain hardening. CREO Parametric software has been proposed to model the two wheeler foot bracket. The modified dimensions and modelling of certain components help to recreate the structure as a better alternative to the existing failure or fractured models. The different views of the CREO Parametric 2D model foot bracket represent the dimensions of the complete structure as shown in

The modelled foot bracket can be subjected to analysis with the help of ANSYS software. We have done our solid modelling part design by using the latest version of Creo Parametric only. The simulation part has been done by using ANSYS 15, and the post processing output images have been modified with the most recent version of ANSYS 15. The application of software is recommended for prediction of performance of the foot bracket before the application of workouts or real time production of certain components. To begin, the modelled foot bracket can be used to create simulations with their corresponding material properties and successive mesh generations. The determined values of each young’s modulus, density and poisons ratio as shown in

After enactment of the element, material properties, and meshing of the modelled foot bracket, the boundary conditions were applied to both the screwed holes at the front side and rear side of the foot bracket panel. The displacement becomes zero at the fixed holes. It was observed in real time that the collar end of the foot bracket was treated as a sensitive location for fracture. It leads to frequent failures over fluctuating loads. Specific attention was given to the collar end of the foot bracket in terms of designing the diameter of the curve and arc-shaped structure with exceptionally fine dimensions. The Finite Element Analysis procedure was adopted for the purpose of finding the withstanding levels of bending moments and stresses with the assistance of changes in material compositions. So various hybrid metal matrix composite structures were planned to do analysis and simulations. The boundary conditions have been applied to this foot bracket structure in the form of the screwed-in end on both ends of the vehicle’s body chassis. The negative directional load is acting on the collar joint nodes of the foot bracket that was defined with the displacement function, which is not equal to zero. Because the load acting direction is not exactly perpendicular to the axis of the panel, there is a change of inclination between the datum axis of the foot bracket panel and the collar vertical. This collar arrangement has been allocated a 450 inclined position in this design. The 750 N loads, which is half the equivalent of the human pushing effort, are applied as downward motion over the meshed model of the foot bracket. After solving the intricate shaped foot bracket meshed model, nodal stress and nodal displacement have been computed under the principles of von Mises.

To validate results obtained from the ANSYS software, real time prototype-based mathematical modelling can be developed. By solving the partial differential equation with particular boundary value problems in two or three independent parameters, the standard mathematical modelling technique has been incorporated for these research findings. Let us consider the foot bracket as a simple cantilever beam having a total length of “l” metre that has been fixed at the bolted end as shown in

By using the double integration method of cantilever beam with the concentrated load is acting at the free end as displayed in

where E-Young’s Modulus and I-Moment of Inertia.

To find the deflection of the intricate cross section of the foot bracket, the

The Centre of Gravity (C.G) of the foot bracket has been calculated by considering the horizontal and vertical distances as mentioned in the ^{6} mm^{4}. The deflection

For considering the entire length of the foot bracket, the deflection is maximum at the load acting end, then the

Similarly, stress (σ) attained due to bending load over the foot bracket panel is given by

where, M – Bending Moment about the section neutral axis. (N/m^{2})

y – Perpendicular distance from the neutral axis to the point of intersection (m)

I – Moment of Inertia of the section area about the neutral axis (m^{4})

Then, substitute the expression of “y” in

The stress and displacement values of Eighteen HMMC obtained with the help of simulation are listed in

The stress obtained from the ANSYS simulation results of each composite material combination is mentioned in

Sl. No. | Composite | Nodal stress max (N/m²) | Nodal displacement (m) |
---|---|---|---|

1. | (a) 85%Al6061-T6+8%SiC+7%TiC | 1398.18 | 8.00E−08 |

(b) 85%Al6061-T6+10%SiC+5%TiC | 4352 | 9.62E−08 | |

(c) 85%Al6061-T6+12%SiC+3%TiC | 2279.06 | 9.17E−08 | |

2. | (a) 85%Al6061-T6+8%SiC+7%Zn | 1272.89 | 1.04E−07 |

(b) 85%Al6061-T6+10%SiC+5%Zn | 2269.43 | 1.07E−07 | |

(c) 85%Al6061-T6+12%SiC+3%Zn | 4433.69 | 1.26E−07 | |

3. | (a) 85%Al6061-T6+8%SiC+7%Gr | 3344.04 | 1.06E−07 |

(b) 85%Al6061-T6+10%SiC+5%Gr | 5398.09 | 1.46E−07 | |

(c) 85%Al6061-T6+12%SiC+3%Gr | 1549.85 | 1.13E−07 | |

4. | (a) 85%Al7075-T6+8%SiC+7%TiC | 4433.69 | 8.84E−08 |

(b) 85%Al7075-T6+10%SiC+5%TiC | 1278.67 | 7.98E−08 | |

(c) 85%Al7075-T6+12%SiC+3%TiC | 4352.91 | 1.03E−07 | |

5. | (a) 85%Al7075-T6+8%SiC+7%Zn | 1525.83 | 1.01E−07 |

(b) 85%Al7075-T6+10%SiC+5%Zn | 1266.13 | 1.00E−07 | |

(c) 85%Al7075-T6+12%SiC+3%Zn | 3528.77 | 1.12E−07 | |

6. | (a) 85%Al7075-T6+8%SiC+7%Gr | 4430.67 | 1.31E−07 |

(b) 85%Al7075-T6+10%SiC+5%Gr | 1443.69 | 1.14E−07 | |

(c) 85%Al7075-T6+12%SiC+3%Gr | 5400.23 | 1.38E−07 |

The results obtained from the simulation software are depicted in the graph (^{2} for the composite material form of 85%Al7075+12%SiC+3%Gr. In addition, the higher value of stress was obtained as 5398.09 N/m^{2} for the Al6061+10%SiC+5%Gr composite form. Based on these results, the 15% SiC and Graphite additions with 85% of matrix alloy formation has delivered the good results. Their consistent nodal displacements are also 1.38E^{−07} and 1.46E^{−07} m, respectively.

The combination of matrix and reinforcements has contributed to the outstanding performance in terms of maintaining maximum stress and minimum displacement. It was achieved with the combined contribution of SiC, TiC, and graphite reinforcement particles. The combination of these reinforced particles in the metal matrix composite improved the strength, stiffness, and hardness (Atrian et al. [

Out of 18 HMMC, two HMMC have been selected for validation of simulation outcome of displacement value with the mathematical models, and the results are listed in ^{−06} m to 9.44E^{−06} m for the composite of Al6061-SiC-Zn. Then it can withstand the highest displacement during the fluctuating load conditions and irrelevant load acting directions. There is no such elevation that was observed using TiC as reinforcement.

Sl. No. | Work piece | Simulation results of displacement (m) | Mathematical model results of displacement (m) | Variation |
---|---|---|---|---|

1. | 85%Al6061-T6+8%SiC+7%Zn | 0.000000108 | 0.000008153 | −14.559 |

2. | 85%Al7075-T6+10%SiC+5%Zn | 0.0000001075 | 0.0000062423 | 0.231 |

Materials | Nodal stress (N/m²) | Nodal displacement (m) |
---|---|---|

Al6061 HMMC | 2890.856667 | 0.000000108 |

AL7075 HMMC | 3073.398889 | 0.0000001075 |

The comparison has made among the average values of Nodal Stress and Displacement of Al6061 HMMC and Al7075 HMMC’s shown in ^{2} has been attained by the Al7075 HMMC’s. This was mentioned in

By exercising the simulation and mathematical modelling of two-wheeler foot, the following conclusions have been arrived at:

Modeling and analysis of the two-wheeler foot bracket was carried out using CREO and ANSYS Software.

According to the simulation results, the composite of 85% Al7075-T6+12%SiC+3% TiC can withstand maximum stress of 5400.23 N/m^{2} and minimum displacement of 46 × 10^{−07} m. It was achieved with the combined contribution of SiC and TiC reinforcement particles with Zn inclusions. The combination of SiC and TiC reinforced particles in the metal matrix composite improved the strength, stiffness, and hardness of the foot bracket, which led to its acting as a fracture shield.

The simulated model is treated as an accurate Simulation results have been validated with the developed mathematical model that provides the least difference of 0.231%.

The identified combination of 85%Al7075-T6+12%SiC+3%TiC Hybrid Metal matrix Composite and Al6061+10%SiC+5%Gr HMMC has provided better structural stability that can withstand the load fluctuations on the foot bracket.

The authors would like to thank their research supervisors, technicians for their esteemed guidance and technical supports throughout the research. The author would also wish to acknowledge the co-authors for supporting this research project.