THE ELASTIC-PLASTIC PROPERTIES OF SYNTACTIC PERFORATED HOLLOW SPHERE STRUCTURES

Hollow sphere structures are lightweight materials and belong to the group of cellular metals (such as metal foams). Metal foams exhibit a several interesting mechanical properties. This contribution investigates the elastic-plastic properties of a new type of hollow sphere structures. For this new type, the sphere shell is perforated by several holes in order to open the inner sphere volume for the matrix material. The effective elastic-plastic properties of syntactic (i.e. spheres embedded in a matrix) perforated sphere structures in a primitive cubic arrangement of unit cell models are numerically evaluated for a different filler fractions of the spheres. The results are compared to configurations without perforation and configurations where hollow spheres are only connected by so called “sintering necks”, i.e. not completely embedded in a supporting matrix. In the scope of this study, threedimensional finite element analysis is used in order to investigate unit cell models. The present investigation revealed that sintered arrangement of perforated hollow sphere structure is superior in terms of initial yield stress compared to the syntactic arrangement counterparts. The stronger structure possessed by sintered arrangement model is attributed to network of sphere morphology. The results also indicate a continuous cubic curve of 0.2% offset yield stress for syntactic and sintered arrangement models.

[1]  A. Öchsner,et al.  Prediction of the elastic properties of syntactic perforated hollow sphere structures , 2012 .

[2]  Andreas Öchsner,et al.  Numerical investigation of the initial yield surface of perforated hollow sphere structures (PHSS) in a primitive cubic pattern , 2011 .

[3]  A. Taşdemirci,et al.  Split Hopkinson pressure bar multiple reloading and modeling of a 316 L stainless steel metallic hollow sphere structure , 2010 .

[4]  M. Merkel,et al.  Numerical Simulation of the Mechanical Properties of Sintered and Bonded Perforated Hollow Sphere Structures (PHSS) , 2010 .

[5]  Markus Merkel,et al.  Predicting the effective thermal conductivity of Perforated Hollow Sphere Structures (PHSS) , 2010 .

[6]  M. Merkel,et al.  Simulation of the Impact Behaviour of Diffusion-Bonded and Adhered Perforated Hollow Sphere Structures (PHSS) , 2009 .

[7]  M. Merkel,et al.  Finite element simulation of the thermal conductivity of perforated hollow sphere structures (PHSS): Parametric study , 2009 .

[8]  M. Merkel,et al.  Numerical Prediction of the Effective Thermal Conductivity of Perforated Hollow Sphere Structures , 2009 .

[9]  M. Merkel,et al.  On the Vibroacoustic Behaviour of HSS , 2009 .

[10]  John Banhart,et al.  Aluminium Foam Sandwich Panels: Manufacture, Metallurgy and Applications , 2008 .

[11]  A. Öchsner,et al.  Numerical and experimental analysis of the thermal conductivity of metallic hollow sphere structures , 2008 .

[12]  A. Kaldos,et al.  Lightweight, hollow-sphere-composite (HSC) materials for mechanical engineering applications , 2004 .

[13]  M. Graef,et al.  Structure of Materials: An Introduction to Crystallography, Diffraction and Symmetry , 2004 .

[14]  A. Öchsner,et al.  On the uniaxial compression behavior of regular shaped cellular metals , 2003 .

[15]  J. Jeandrau.  Analysis and design data for adhesively bonded joints , 1991 .