Evaluation of key mechanical design properties and mechanical characteristic features of advanced Bi-2212 ceramic materials with homovalent Bi/Ga partial replacement: Combination of experimental and theoretical approaches

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Küçük Resim

Tarih

2019

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Elsevier Sci Ltd

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

This study models the variations in the key mechanical design properties and mechanical characteristic features of Ga substituted Bi-site Bi-2212 ceramics prepared within the different molar ratios of x = 0.000, 0.005, 0.010, 0.030, 0.050, 0.100 and 0.300 with the assistant of available theoretical approaches; namely, Meyer's law, proportional sample resistance, elastic/plastic deformation, modified proportional sample resistance model, Hays Kendall and indentation-induced cracking methods for the first time. The mechanical modeling parameters are gathered from the microhardness (Vickers) experimental tests performed at various applied loads interval 0.245 N-2.940 N. The results provide that the key mechanical design features improve systematically with the augmentation of trivalent Bi/Ga partial replacement level up to x = 0.05 due to the rapid decrement in the main structural problems; namely, the grain orientations, lattice strains, distortions, dislocations, grain boundary interaction/coupling problems, crack-initiating and crack-producing omnipresent flaws in the advanced Bi-2212 ceramic system. Accordingly, the optimum Ga inclusions strengthens the mechanical durability towards the applied stress due to the increased stabilization in the durable tetragonal phase. After the critical substitution amount of x = 0.05, the mechanism turns reversely, and the general mechanical characteristic features including the stiffness, mechanical durability and strength degrade remarkably. Additionally, the mechanical modeling results demonstrate that the Bi/Ga impurity leads to vary positively the quality of standard indentation size effect (ISE) feature until x = 0.05, beyond which the excess Ga additives damage seriously ISE feature of Bi-2212 inorganic compounds. Besides, the indentation-induced cracking (IIC) model is noticed as the best method to describe the true microhardness parameters of Bi/Ga substituted Bi-2212 compounds for the mechanical characterization.

Açıklama

Anahtar Kelimeler

Bi-2212 Ceramic Compound, Bi/Ga Partial Substitution, ISE Feature, Mechanical Modeling, IIC Approach

Kaynak

Ceramics International

WoS Q Değeri

Q1

Scopus Q Değeri

Q1

Cilt

45

Sayı

17

Künye