Structure and physicomechanical properties of high-porosity copper of different origin

Vibrodeformation properties of construction, composite, and high-porosity sintered materials

“…The mechanical properties of sintered porous materials subject to cyclical deformation (elastic modulus, fatigue strength, and damping properties) are not well understood [23][24][25][26][27][28][29][30][31][32][33][34]. Moreover, there are no codified studies on this subject.…”

“…d p is the diameter of a powder particle, d fa is the diameter of a particle of foaming agent, d f and l f are the diameter and length of a discrete fiber, respectively, and d c is the diameter of a cell in the foamed material. If, however, we restrict ourselves to examination of works devoted to study of mechanical properties of sintered highporosity (Π = 40-98%) copper-base materials subject to cyclical deformation [27][28][29][30][31], all of the above-indicated properties can be evaluated.…”

Damping properties of sintered high-porosity materials based on powders and discrete copper fibers

“…Here, the exponent n takes into account the influence exerted on the elastic modulus by the shape of the pores, degree of perfection of interparticle contacts, and even the loading rate and the ability of the material to relax under load [11]. Let us assume that the elastic modulus of sintered materials based on discrete fibers can be described by relationship (5). For all types of materials investigated, one can then assume that the smaller the exponent n, the higher (5) the value of E for a given porosity, that is the higher the quality of the sintering.…”

“…According to Granovskii et al [5], powder materials produced by the free-fill method have the structure shown in Fig. 1.…”

“…In this study, we investigated high-porosity sintered copper-base materials produced by processes described in [5]: by sintering of freely filled electrolytic PMS-N powders with the developed dendritic particle shape with a diameter of 160-100 μm and 100-60 μm (porosity ranging from 51 to 62%); by pressing with subsequent sintering of mixtures of a disperse (10-30 μm) electrolytic Grade PMS-2 powder, and the powder of a volatile foaming agent with a particle size ranging from 100 to 160 μm (porosity of 62%); and, by sintering copper fibers 3 mm long and 40 μm in diameter (porosity ranging from 40 to 81% The pore structure of the materials was investigated using a metallographic microscope and a mercury porosimeter. According to Granovskii et al [5], powder materials produced by the free-fill method have the structure shown in Fig.…”