Heat Treatment of Aluminium Matrix Composite ( AMC ) Reinforcement Organoclay for Automotive Application

Aluminum Matrix Composites (AMC) reinforced montmorillonite (MMT) was performed using cationic surfactant , Artificial Aging and stir casting method. The content of MMT as a filler is 3%wt. Characterization were performed using Xray Difractometer, ultrasonic testing, SEM, and Hardness Vickers. The results show increase in crystallographic parameter, decrease in density, shiffting in XRD pattern and increase in hardness.


INTRODUCTION
The use of composites in automotive applications increased in decades lately.Modifications composite with a metal alloy ,ceramic, polymers may improve the mechanical properties of the composite can be used instead of steel as the material of automotive applications (B.N.Sarada et al, 2015).
Improved mechanical properties of composites in many research using aluminum as a matrix known as the Aluminum Matrix Composites (AMC) and is reinforced with a filler Bamboo Leaf Slag (BLA) with composition of 0,2,3,4 % Wt (Alaneme K.K., 2013) or increasing lack purity aluminum matrix with another metal alloy (Al-Mg-Si) with a composition of 10 wt% (M.Gupta, M.K. Surappa, 1995) and by using ceramic used to 10 wt% SiC affecting the mechanical properties of the composite ie hardness, elasticity, strain (Chennakesava Reddy A and Sundararajan S, 2005).
Improved AMC to provide reinforcement properties of metal alloys (metal alloy) on a matrix of aluminum will increase the tensile properties of composite (Chennakesava Reddy A and Sundararajan S, 2005).
The addition of a ceramic variations such as TiC, TiC, TiB2 and B4C as filler (filler) on AMC improve material hardness (C.Gonzalez, A et al, 2005).AMC reinforced with polymer will increase strength and stiffness in its matrix (Kashish Goyal and Karthikeyan Marwaha, 2016).Besides heat treatment varied particle size reinvorcement AMC will improve the mechanical properties (mechanical properties) (Sanjay Soni, ajay Pandey, 2014).
In this research aims to improve the mechanical properties of AMC by heat treatment Stir Casting and filler montmorillonite (MMT) organoclay which has a small particle size to the nanoscale (5-10 nano) with the composition of 3wt%, and will increase the mechanical properties the most optimal from a composite that will be used for automotive applications.

Matrix
Aluminium alloy (6061) is selected as matrix alloys for synthesis of AMC.The chemical compositions of aluminium alloy was analyzed using glow discharge spectrometer (Model: GD Profiler 2).

Composite Production
Production of composites made with stir casting process.Stirring were carried out with a rotational speed of 400 rpm, at a temperature of 750 oC.Pouring molten metal into the mold were done with temperature variation cast: 600, 700, 725 and 750 oC.When the matrix was in the completely liquid condition, blending were begun following 2 minutes.Stirrer rpm is steadily expanded from 0 to 400 RPM with the assistance of velocity controller.Temperature of the warmer was set to 600°C which was underneath the softening temperature of the network.A uniform semisolid phase of the liquid lattice was accomplished by blending it at 700 °C.

Heat Treatment
The Sample Al-Organoclay were heat treated in a furnace to look at the properties in matured and as cast condition.There were three phases required in the heat treatment.The sample were heated to a temperature of 490 ± 5 oC for 8 hours until the alloy solute components are totally broken down in the Al solid solution.Extinguishing: the arrangement treated examples were quickly cooled into oil to keep the precipitation of the solute components and to acquire a super soaked strong arrangement and Artificial aging: To enhance the quality and hardness of the material were heated 240 oC for 6 hours each and afterward permitted to cool in the still air [8].

Characterization
The samples in as cast and heat treated condition were then tried for different tests.X-ray diffractometer was used to characterize the crystallography parameter.Measurement of Young modulus of the composite were carried out by ultrasonic testing.Scanning Electron Microscope (JEOL make, Model JSM 6510) was used to observed morphology

Chemical composition
Tabel 1 show the composition of the matrix, Aluminium alloy 6061.

CONCLUSION
Addition of 3%wt MMT in Aluminium decrease density and increase hardness.It seem that this composite (Al alloy+MMT) could be a challence for new application in automotive materials.
Figure 1.XRD pattern of pure and Allumunium Alloy

FigureFigure 3 .Figure 2
Figure 2. XRD pattern of Na-MMT after intercallation Tabel 3. Young Modulus and Hardness Al and Al alloy+MMT Materials Y (Gpa) Hardness Vickers Al 70 150 Al 6061+MMT 75 160 Figure 2 show the shiffting of peak Na-MMT to the left, indicate the pillarized Na-MMT.Tabel 3 show the young modulus and hardness vickers of pure Al and Al alloy+MMT.Figure 3 show morphology of Al+MMT.

Table 1 . Properties of Matrix
ReinforcementModified Na-montmorillonite clay (Na-MMT) with Cation Exchange Capacity, CEC 87.53 meq/100g was supplied by Zhejiang FCC New Material Technology Company Limited .