BCC lattice cell structural characterization

In this work, a numerical characterization of BCC lattice cells is performed through the use of an homogenization approach. The main goal is to establish a relationship among those properties and the relative density of the cubic unit cell. The BCC cell struts diameter are the inputs parameters of the homogenization analysis campaing in order to vary the relative density of the unit cell. A linear periodic condition has been applied to the model in order to simulate a clear probing situation. Traction load tests are used in order to evaluate the Young modulus and the Poisson coefficient, differently a pure shear load case is employed for the evaluation of the shear modulus. Hence the final results will be presented in a graphic visualization.

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Chemical and mineralogical characterization of elbaites from the Alto Quixaba pegmatite, Seridó province, NE Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652005000400011 ◽

2005 ◽

Vol 77 (4) ◽

pp. 729-743 ◽

Cited By ~ 2

Author(s):

Ana C.M. Ferreira ◽

Valderez P. Ferreira ◽

Dwight R. Soares ◽

Hugo S. Vilarroel-Leo

Keyword(s):

Refractive Index ◽

Relative Density ◽

Unit Cell ◽

Northeastern Brazil ◽

Central Portion ◽

Unit Cell Parameters ◽

Mineralogical Characterization ◽

Cell Parameters ◽

Average Relative Density

The Alto Quixaba pegmatite, Seridó region, northeastern Brazil, is a 60º/80ºSW-trending subvertical dike discordantly intruded into biotite schists of the Upper Neoproterozoic Seridó Formation. It has three distinct mineralogical and textural zones, besides a replacement body that cuts the pegmatite at its central portion and in which occur, among other gem minerals, colored elbaites. Elbaites usually occur as prismatic crystals, elongate according to the c-axis, with rounded faces and striations parallel to this axis. Optically, crystals are uniaxial negative with strong pleochroism; refractive index extraordinary axis = 1.619-1.622 and ordinary axis = 1.639-1.643, birefringence between 0.019 and 0.021, average relative density of 3.07, and the following unit cell parameters: ao = 15.845 Å, co = 7.085 Å and V = 1540.476 Å. There is alkali deficiency in the X site of 12-17%. The elbaites are relatively enriched in MnO (1.69 to 2.87%) and ZnO (up to 2.98%).

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Effective Design of the Graded Strut of BCC Lattice Structure for Improving Mechanical Properties

Materials ◽

10.3390/ma12132192 ◽

2019 ◽

Vol 12 (13) ◽

pp. 2192 ◽

Cited By ~ 3

Author(s):

Long Bai ◽

Changyan Yi ◽

Xiaohong Chen ◽

Yuanxi Sun ◽

Junfang Zhang

Keyword(s):

Mechanical Properties ◽

Stress Concentration ◽

Relative Density ◽

Lattice Structure ◽

Design Method ◽

Unit Cell ◽

The Body ◽

Future Research ◽

Force Model ◽

Bcc Lattice

In order improve the poor mechanical properties of the body-centred cubic (BCC) lattice structure, which suffers from the stress concentration effects at the nodes of the BCC unit cell, a graded-strut design method is proposed to increase the radii corner of the BCC nodes, which can obtain a new graded-strut body-centred cubic (GBCC) unit cell. After the relative density equation and the force model of the structure are obtained, the quasi-static uniaxial compression experiments and finite element analysis (FEA) of GBCC samples and BCC samples are performed. The experimental results show that for the fabricated samples with the same relative density, the GBCC can increase the initial stiffness by at least 38.20%, increase the plastic failure strength by at least 34.12%, compared with the BCC. Coupled experimental and numerical results not only suggest that the GBCC has better mechanical and impact resistance properties than the BCC, but also indicate that as the radii corner increases, the stress concentration effect at the node and the mechanical properties will be improved, which validates the proposed design method for graded-strut unit cells and can provide guidance for the design and future research on ultra-light lattice structures in related fields.

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