Structural Analysis Of Delamination Of Composite Materials Using Vertical Milling Machine (GFRP)

Transcription

1 Structural Analysis Of Delamination Of Composite Materials Using Vertical Milling Machine (GFRP) B.Bindu madhavi #1, S.Suresh *2 1 M. Tech-(CAD-CAM), Siddharth Institute Engineering and Technology, Puttur 2 Associate Pressor, Siddharth Institute Engineering and Technology, Puttur ABSTRACT The composite materials were available in the olden days in many forms there has been a tremendous research in the area because its high strength to weight ratio especially in structural applications. This project deals glass fibre reinforced polymer (GFRP) composite. Fibre glass reinforced plastic are made a plastic matrix reinforced by fine fibers glass. GFRP is light weight, extremely strong,and robust material. Machining involves the removal any extra or unwanted material. The maerial removal mechanism FRP is very difficult as compared with metals due to their homogeneity and anisotropy. The delamination that occurs during milling severly influences the mechanical charecterstics the material. In order to avoid these problems it is necessary to determine the delamination occurring due to machining operation. In order to understand the effects process parameters on the delamination a large number machining experiments have to be performed and analyzed using FEM model. Using FEM model the desired cutting and material parameters for minimized appearance delamination has been developed. Key Words: GFRP, PRO/E(Creo parametric 1.0), ANSYS, Finie element analysis. I. INTRODUCTION A) composite A composite material is an anisotropic, heterogeneous medium, made by combining two or more materials with differing properties. Properties the composite are different from those the constituent materials. The components the composite do not merge completely in to each other and can be physically identified along with the interface between them. The properties the interface also contribute to the properties the composite. Carbon Fiber Glass Fiber Aramid (Kevlar) Fiber Grades glass fiber which the following are the most common: E-glass - Good electrical insulator and high strength. C-glass - Good chemical corrosion resistance. S-glass - High silica content with high temperature performance, high strength and stiffness military grade. R-glass - Civil version S-glass. A-glass - High alkali content for chemical resistance. D-glass - Low dielectric and low density. L glass - High lead content for radiation protection. Glass fiber is available in the following forms 1. Continuous Fiber 2. Chopped strands 3. Woven B) Types Fiber: ISSN: Page 2306

2 Fig 1 : Continuous Fiber Table 1: The general application and properties composites Fig 2 : Chopped Strands II. DELAMINATION Delamination is defined as the separation the layers material in a laminate. Delamination can occur at any time in the life a laminate for various reasons and has various effects. It can affect the tensile strength performance depending on the region Delamination. Among the various defects that are caused by drilling, Delamination is recognized as the most critical. Other defects are spalling and fiber pullout, but Delamination can result Application composite material: The general application and properties composites are listed in Table Application Aerospace Chemical/Marine Automobile Properties Low weight,high strength, High modules. Corrosion resistance Formability and tailor ability polymer composites in a reduction in the durability the composite material and can cause a reduction in the bearing strength the material and the structural integrity, resulting in performance issues. The Delamination in composite are shown in Fig1.4. Delamination factor is defined by ratio maximum diameter ( damaged zone around hole) to actual diameter. High temperature application Ceramic composites Delamination factor = D max /D actual Where Modulu s elasticit y Bulk modulus Poiss on s ratio tensile stress tensile stress D max is damaged diameter D actual real diameter to be machined (Xdirectio n) 48 (Ydirection ) (X-direction) 550 MPa (Y-direction) 34 MPa ISSN: Page 2307

3 Table 2: Specimen-I Material properties GFRP Bulk modulus Poisson s ratio tensile stress tensile stress (Xdirection ) 75 (Ydirection) (Xdirection) MPa (Ydirection) 25 MPa Table 3: Specimen-II Material properties GFRP Fig 6: Specimen- I Meshing GFRP Fig 3: Modeling Fig 7: Specimen- II Meshing GFRP Fig 4: Modeling GFRP specimen-i Fig 5: Modeling GFRP specimen-ii ISSN: Page 2308

4 fig 8: Layers GFRP specimen-i Fig 12: Nodal solution for GFRP specimen-ii in fig 9: Layers GFRP specimen-ii III. RESULTS AND DISCUSSION : Fig 13: Delamination GFRP specimen-ii in IV. COMPARISONS OF EXPERIMENTAL AND SIMULATION RESULTS The results obtained from the experimental testing and simulations have been compared are shown in the table 3.7. It has been found out that the discussed FEA model results are close to be experimental results. Specimen Delamination in experimental results (mm) Delamination in FEA results (mm) Fig 10: Nodal solution for GFRP specimen-i in I II Table 4 : Comparisons experimental and simulation results V. CONCLUSION Fig 11: Delamination GFRP specimen-i in The Delamination that occurs during milling severely influences the mechanical characteristics the material. In order to avoid these problems it is necessary to determine the Delamination occurring due to machining operation. In order to understand ISSN: Page 2309

5 the effects process parameters on the Delamination a large number machining experiments have to be performed and analyzed using FEM model. Using FEM model the desired cutting and material parameters for minimized appearance delamination has been developed. It has been found out that the discussed FEA model results are close to be experimental results. The 3D FEM models are applied to milling and after simulations it is adaptable to industry REFERENCES [9] Dipaolo G, Kappor SG, Devor RE (1996) An experimental investigation the crack growth Phenomenon for drilling fiberreinforced composite materials. J Eng Ind, ASME pp. 118: [10] W.-C. Chen, (1997) some experimental investigations in the drilling carbon fiber-inforced plastic (CFRP) composite laminates, International Journal Machine Tools and Manufacture pp [1] Bhatnagar, N., Ramakrishnan, N., Naik, N.K., and. Komandurai, R., (1995), On the machining fiber Reinforced plastics (FRP) composite laminates, Int J.Machine Tool Manuf., 35 (5), pp [2] Davim, JP. Mata, F. (2004), Influence cutting parameters on surface roughness using statistical analysis. Indus Lubrication Tribol, 56(5), pp [3] J.R. Ferrira, N.L.coppini, G.W.A.Miranda, (1999) machining optimation in carbon fiber reinforced composite material, journals Material Processing Technology, pp.92-93: [4] H. Hocheng, C.C. Tsao, (2004) Analysis delamination in drilling composite materials using core drill, Aust. J. Mech. Eng. pp [5] H.Z. Li, X.P. (2002), Li, Milling force prediction using a dynamic shear length model, Int. J. Mach. Tools Manuf. Vol. 42, PP [6] W.-S. Yun, D.-W. Cho, (2001), Accurate 3-D cutting force prediction using cutting condition independent coefficients in, Int. J. Mach. Tools Manuf. Vol. 41 PP [7] M.C. Yoon, Y.G. Kim, (2004), Cutting force modeling operation, J. Mater. Process. Technol, Vol PP [8] Y.Altintas, ( 2000) Manufacturing Automation, Cambridge University Press, P. L. B. Oxley: The Mechanics Machining PP.67 ISSN: Page 2310