Pınar Aydan Demirhan

This paper presents a static analysis for simply supported sandwich plate with foam core by using refined plate theory. Face layers of the sandwich plate are assumed isotropic, core of the sandwich is assumed foam. In the bending of sandwich plates, the bending load is carried by face layers while the transverse shear loads are carried mainly by the core. There are many papers in the literature on the analysis of the bending, buckling and vibration of sandwich structures. Classical lamination theory, first order shear deformation theory and various shear deformation theories are applied for analysis of sandwich plates. In this study static analysis for simply supported sandwich plate is investigated. Governing equations are derived from the principle of virtual displacements. A closed-form solution is found by using the Navier’s method. Numerical results are performed parametrically. The effect of density and pore size of foam on stress distribution through thickness are investigated.

In this study, it is aimed to analyze the bending of porous sandwich plates using the four-variable shear deformation theory. The core of the sandwich plate is assumed to be functionally graded, and face sheets are assumed to be isotropic. The pore distribution of the sandwich plate is considered even and uneven type of porosity distribution. Displacement fields are defined with four variable shear deformation theory. Equilibrium equations of porous sandwich plates are derived from virtual displacement principle. An analytical solution is obtained by Navier's approach. Results are presented for uniformly and sinusoidally distributed loaded porous sandwich plates. Face sheet -core thickness ratio, porosity distribution, amount of porosity is investigated.

In the present study, the large deflection of thin inextensible bimodulus functionally graded foam cantilever beams with rectangular cross sections subjected to an end moment at the free end is studied. Ludwick type constitutive material properties are assumed. Different stress-strain relations are used in tension and compression domain. Linear Young’s modulus variation is assumed in the thickness direction. Vertical and horizontal deflections of free end and position of neutral surface are given for different material properties. Deflections at the free end for bimodulus cantilevered foam beams can be optimized using functionally grading exponents.

In last decades functionally graded materials become very popular for lots of industries such as automotive, naval, railroad, aerospace, etc. There are many papers in literature for bending, stability and vibration analysis of functionally graded plates. In this paper, bending of simply supported functionally graded square plates are studied. For functionally graded plates many shear deformation theory is offered. Various shape functions for defining displacement fields are used in these theories. In this study, several shape functions are discussed for deflection and stress distribution of functionally graded plate with sinusoidal loading. The exponential gradient form is assumed for change of material properties through thickness direction. Refined plate theory with different shape functions is used. Governing equations are derived from the principle of virtual displacements. The solution is obtained by Navier’s double trigonometric series approach. Numerical results of deflection...

Abstract In this study, the effect of size and fraction of SiCp on compressive behavior of composite metal foam were investigated. Compare to the same relative density of composite foam, plateau stress and energy absorption increased with increasing fraction of SiCp. ...

This paper aims to investigate the free vibration and bending characteristics of porous functionally graded (FG) plate with two opposite simply supported edges based on a four variable plate theory. Material properties of porous FG plate are defined by rule of the mixture with an additional term of porosity in the through-thickness direction. Equations of motion are derived using Hamilton principle. State-space approach is used to obtain the governing equation of porous FG plate. The effect of porosity parameter, slenderness ratio, and the power-law index is investigated on bending and vibration of porous FG plate. The results are compared with available results in the literature to verify this theory.

Fonksiyonel derecelendirilmis malzemeler geleneksel malzemelerin uygun olmadigi calisma kosullari icin tasarlanmis ozel bir kompozit malzeme sinifidir. Malzeme ozellikleri istenen dogrultuda bir fonksiyona bagli olarak degismektedir. Malzeme ozelliklerinde keskin gecisler olmamasi nedeniyle katmanli kompozit yapilarda karsilasilan problemleri ortadan kaldiran fonksiyonel derecelendirilmis malzemeler sandvic yapilar icinde oz veya yuzey tabakasi olarak kullanilabilmektedir. Bu calismada fonksiyonel derecelendirilmis sandvic kirislerin titresim analizi yapilmistir. Sandvic kirisin yuzey tabakalari fonksiyonel derecelendirilmis, oz tabakasi izotropik malzeme olarak kabul edilmistir. Sandvic kirisin yer degistirme bilesenleri Euler-Bernoulli kiris teorisi ile tanimlanmis, farkli sinir kosullari icin elde edilen kiris denklemi transfer matris metodu ile cozulmustur. Sandvic oz ve yuzey tabakasi kalinlik oranlarinin ve hacimsel degisim ustelinin degisiminin dogal frekansin degisimi uzerin...

Abstract: In this study, closed cell AlMg4. 5Mn0. 7/SiCp composite metal foam were produced by direct foaming at semisolid temperature. Effect of reinforcement size and fraction on linear expansion, relative density and pore distribution were investigated. With ...