Thermal Expansion of Copper and Nickel Sulfides and their Alloys

2013 ◽  
Vol 334-335 ◽  
pp. 55-59 ◽  
Author(s):  
Evgeny N. Selivanov ◽  
O.V. Nechvoglod ◽  
R.I. Gulyaeva

Thermal expansion coefficients of metal sulfides and their alloys are important for technological processes calculations of sulfide processing materials, for example, the crystallization equipment of nickel and copper-nickel converter matte. The synthesized copper and nickel monosulfide, and nickel and copper-nickel matte have been used as the initial samples. Dilatometric analysis was carried out by dilatometer (Linseis L78 RITA). Differences in the values measured are accounted for by the synthesis samples facilities, the coexistence of several non-stoichiometric sulfide phases and interaction during heating. In the temperature 20-500°C range the coefficients of thermal expansion (α) for the sulfides of copper, nickel and their alloys are changed from 10.4 to 20.610-6 1/K. Changes in the value α are accounted for by phase transitions in sulfide samples at their heating. Considering the properties of the phase components are an additive it is shown the thermal expansion coefficient complex sulfide-metal alloys is possible to calculate.

2016 ◽  
Vol 30 (11) ◽  
pp. 1650127 ◽  
Author(s):  
Yi Ren ◽  
Wen Ma ◽  
Xiaoying Li ◽  
Jun Wang ◽  
Yu Bai ◽  
...  

The SOFC interconnect materials La[Formula: see text]Sr[Formula: see text]Cr[Formula: see text]O[Formula: see text] [Formula: see text]–[Formula: see text] were prepared using an auto-ignition process. The influences of Cr deficiency on their sintering, thermal expansion and electrical properties were investigated. All the samples were pure perovskite phase after sintering at 1400[Formula: see text]C for 4 h. The cell volume of La[Formula: see text]Sr[Formula: see text]Cr[Formula: see text]O[Formula: see text] decreased with increasing Cr deficient content. The relative density of the sintered bulk samples increased from 93.2% [Formula: see text] to a maximum value of 94.7% [Formula: see text] and then decreased to 87.7% [Formula: see text]. The thermal expansion coefficients of the sintered bulk samples were in the range of [Formula: see text]–[Formula: see text] (30–1000[Formula: see text]C), which are compatible with that of YSZ. Among the investigated samples, the sample with 0.02 Cr deficiency had a maximum conductivity of 40.4 Scm[Formula: see text] and the lowest Seebeck coefficient of 154.8 [Formula: see text]VK[Formula: see text] at 850[Formula: see text]C in pure He. The experimental results indicate that La[Formula: see text]Sr[Formula: see text]Cr[Formula: see text]O[Formula: see text] has the best properties and is much suitable for SOFC interconnect material application.


2006 ◽  
Vol 947 ◽  
Author(s):  
Kyung Choi

ABSTRACTHigh resolution pattern transfers in the nano-scale regime have been considerable challenges in ‘soft lithography’ to achieve nanodevices with enhanced performances. In this technology, the resolution of pattern integrations is significantly rely on the materials' properties of polydimethylsiloxane (PDMS) stamps. Since commercial PDMS stamps have shown limitations in nano-scale resolution soft lithography due to their low physical toughness and high thermal expansion coefficients, we developed stiffer, photocured PDMS silicon elastomers designed, specifically for nano-sized soft lithography and photopatternable nanofabrications.


1985 ◽  
Vol 82 (3) ◽  
pp. 1611-1612 ◽  
Author(s):  
Stanley L. Segel ◽  
H. Karlsson ◽  
T. Gustavson ◽  
K. Edstrom

Author(s):  
Jonathan B. Hopkins ◽  
Lucas A. Shaw ◽  
Todd H. Weisgraber ◽  
George R. Farquar ◽  
Christopher D. Harvey ◽  
...  

The aim of this paper is to introduce an approach for optimally organizing a variety of different unit cell designs within a large lattice such that the bulk behavior of the lattice exhibits a desired Young’s modulus with a graded change in thermal expansion over its geometry. This lattice, called a graded microarchitectured material, can be sandwiched between two other materials with different thermal expansion coefficients to accommodate their different expansions or contractions caused by changing temperature while achieving a desired uniform stiffness. First, this paper provides the theory necessary to calculate the thermal expansion and Young’s modulus of large multi-material lattices that consist of periodic (i.e., repeating) unit cells of the same design. Then it introduces the theory for calculating the graded thermal expansions of a large multimaterial lattice that consists of non-periodic unit cells of different designs. An approach is then provided for optimally designing and organizing different unit cells within a lattice such that both of its ends achieve the same thermal expansion as the two materials between which the lattice is sandwiched. A MATLAB tool is used to generate images of the undeformed and deformed lattices to verify their behavior and various examples are provided as case studies. The theory provided is also verified and validated using finite element analysis and experimentation.


2017 ◽  
Vol 32 (S2) ◽  
pp. S38-S42
Author(s):  
Matthew R. Rowles ◽  
Cheng-Cheng Wang ◽  
Kongfa Chen ◽  
Na Li ◽  
Shuai He ◽  
...  

The crystal structure and thermal expansion of the perovskite samarium cobalt oxide (SmCoO3) have been determined over the temperature range 295–1245 K by Rietveld analysis of X-ray powder diffraction data. Polycrystalline samples were prepared by a sol–gel synthesis route followed by high-temperature calcination in air. SmCoO3 is orthorhombic (Pnma) at all temperatures and is isostructural with GdFeO3. The structure was refined as a distortion mode of a parent $ Pm{\bar 3}m $ structure. The thermal expansion was found to be non-linear and anisotropic, with maximum average linear thermal expansion coefficients of 34.0(3) × 10−6, 24.05(17) × 10−6, and 24.10(18) × 10−6 K−1 along the a-, b-, and c-axes, respectively, between 814 and 875 K.


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