Clamping Effect on Welding Deformations in Dissimilar Welded Clad With Varied Thickness; Axial and Radial Shrinkage and Deformation

2021 ◽  
Author(s):  
Bridget Kogo ◽  
Bin Wang ◽  
Mahmoud Chizari
Keyword(s):  
Radial Shrinkage

Wood Dimensional Changes due to Hygrothermal Behaviour

2015 ◽  
Vol 365 ◽  
pp. 172-177
Author(s):  
V.P. de Freitas ◽  
João M.P.Q. Delgado ◽  
N. Machado
Keyword(s):  
Relative Humidity ◽  
Linear Thermal Expansion ◽  
Strong Variation ◽  
Dimensional Changes ◽  
Radial Shrinkage ◽  
Dimension Stability ◽  
Definition Of ◽  
Hygrothermal Behaviour ◽  
Shrinkage Coefficient

Wood has a strong hygroscopic behaviour, with a strong variation of moisture content and dimension stability caused by modifications of the relative humidity of the surrounding air. The properties that define the behaviour of wood facing temperature and moisture actions were studied in this work. Linear thermal expansion, hygroscopicity, shrinkage (tangential and radial shrinkage coefficient) and hygric expansion were given special attention.An experimental device was designed for testing wood samples, red oak. A series of tests was performed including the determination of hygric expansion coefficient and the definition of the sorption curve. This research made possible the evaluation of dimensional stability of wood in transient conditions of relative humidity.

Shrinkage Behaviour of Borosilicate Glass-Al2O3 Composites during Isothermal Sintering

2006 ◽  
Vol 514-516 ◽  
pp. 648-652
Author(s):  
M.M.R.A. Lima ◽  
Regina da Conceição Corredeira Monteiro
Keyword(s):  
Borosilicate Glass ◽  
Capillary Flow ◽  
Density Measurement ◽  
Al2o3 Content ◽  
Matrix Composites ◽  
Dense Microstructure ◽  
Shrinkage Behaviour ◽  
Radial Shrinkage ◽  
Sintering Behaviour ◽  
Glass Matrix Composites

The effect of rigid inclusions on the densification during isothermal sintering of glass matrix composites was investigated. Mixtures containing borosilicate glass powder and 0, 5, 10 and 25 vol. % alumina (Al2O3) particles were prepared and powder compacts isostatically pressed at 200 MPa have been used. The sintering behaviour of the samples heated at 800°C during various times was investigated through density measurement, axial and radial shrinkage measurements. The microstructure was analysed by SEM and the crystalline phases present in the sintered composites were identified by XRD. The relative density of the isothermally treated borosilicate glass-Al2O3 composites decreased significantly with the increase in Al2O3 content because the presence of rigid inclusions retarded the densification of the compacts. The borosilicate glass exhibited anisotropic shrinkage behaviour, showing a radial shrinkage higher than the axial shrinkage and isotropic shrinkage was favoured by Al2O3 additions. Sintered glass showed a dense microstructure with some spherical closed pores. The microstructure of composites with 5 vol. % Al2O3 revealed that most of the pores were filled by capillary flow of the glass. The microstructure of composites with higher Al2O3 additions showed dense areas together with interconnected pores, which appeared at the sites of large glass particles in the green compacts.

scholarly journals Intriguing uniform elongation and accelerated radial shrinkage in an amorphous SiOxnanowire as purely induced by uniform electron beam irradiation

RSC Advances ◽  
2017 ◽  
Vol 7 (72) ◽  
pp. 45691-45696 ◽  
Author(s):  
Jiangbin Su ◽  
Xianfang Zhu
Keyword(s):  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Uniform Elongation ◽  
Beam Irradiation ◽  
Plastic Elongation ◽  
Radial Shrinkage

The nanowire demonstrates a tensile pulling-free uniform plastic elongation and an accelerated radial shrinkage at nanoscale under uniform e-beam irradiation.

Relative Importance of Defects in Girth Welds of Linepipes

2007 ◽  
Author(s):  
Oddvin O¨rjasaeter ◽  
Per J. Haagensen ◽  
Hans Olav Knagenhjelm
Keyword(s):  
Small Scale ◽  
Test Results ◽  
Gas Field ◽  
Loading Mode ◽  
Radial Shrinkage ◽  
Welding Defects ◽  
Scale Test ◽  
Girth Welds ◽  
Pipeline Design ◽  
Compressive Residual Stresses

The Ormen Lange deepwater gas field is located at water depth down to 1100 meters. The irregular seabed gives severe challenges to pipeline design and verification program was launched to demonstrate adequate fatigue capacity. The research included: modern welding techniques (5G and 2G welding positions), mapping of actual welding defects, misalignment (high/low) and lack of penetration. The thick walled pipe (35mm) showed low or even compressive residual stresses at the inside. This will to some extent be “protective” to the root of the weld. The exceptions to this pattern were the repair welds and the two-sided welds. The small scale test results fell close to the full scale pipe tests when taking into account the geometrical weld distortions, loading mode, and the distribution of weld defects. The importance of the parameters influencing the fatigue capacity could be ranged as follows, most detrimental first: large crack-like defects (LOP, undercut > 1mm), hi/lo, and V-shape (radial shrinkage at the girth weld).

scholarly journals Wood physical properties, color, decay resistance and stiffness in Tectona grandis clones with evidence of genetic control

2013 ◽  
Vol 62 (1-6) ◽  
pp. 142-152 ◽  
Author(s):  
R. Moya ◽  
J. D. Marín ◽  
O. Murillo ◽  
L. Leandro
Keyword(s):  
Clonal Selection ◽  
Tectona Grandis ◽  
Wood Properties ◽  
Decay Resistance ◽  
Clonal Variation ◽  
Blue Color ◽  
Limited Information ◽  
Pycnoporus Sanguineus ◽  
Radial Shrinkage ◽  
Improvement Programs

AbstractTectona grandis (teak) plantations are being produced with trees from genetic improvement programs, including clonal selection. However, limited information about inheritance of wood properties is available. For studying genetic parameters of T. grandis wood properties and stem diameter two 10-yr-old trials were studied involving nominally 2 sites × 20 clones × 3 replicates × 1 ramet. Clonal variation was observed in: heartwood (HWP), pith (PP) and bark (BP) percentages; green moisture content (IMC) and density (GD); tangential (TS), radial (RS) and volumetric (VS) shrinkage and ratio tangential/radial: shrinkage (ratio T/R); L*a*b* color parameters; and stiffness and specify gravity (SG). Some wood properties evidenced strong across-sites genotypic control. The higher broad-sense heritability estimates (over 0.36) were for PP, IMC, SG, TS, VS and L*, a*, and b* color coordinates and stiffness. Low and non-significant values were estimated for HWP, BP, GD, RS, ratio T/R and decay resistance of sapwood and heartwood to Trametes versicolor and Pycnoporus sanguineus. However, HWP showed marked clone x site interaction. Phenotypic and tentatively estimated genotypic correlations indicate that selecting faster-growing clones will improve some important wood properties, such as increasing HWP, and decreasing PP and BP, without affecting other wood properties. Selecting clones for denser wood, as expected, improved stiffness, should decrease IMC and affect negatively b* (yellow/blue) color. Clone selection with lower L* values could increase redness (a*) of wood.

Characterization of Doped Titanium Oxide Varistor Powder Processed with Latex Binder

2015 ◽  
Vol 1115 ◽  
pp. 133-136
Author(s):  
Shahida Begum ◽  
Ida Rasyada ◽  
Arvin Panimeerselvam
Keyword(s):  
Grain Size ◽  
Silicon Oxide ◽  
Ceramic Materials ◽  
Sem Analysis ◽  
Electrical Performance ◽  
Green Density ◽  
Micro Hardness ◽  
Radial Shrinkage ◽  
Average Grain Size

In the processing of semiconducting electro ceramic materials the use of appropriate binder can lead to improve characteristics of powder which will reduce density gradient in the green body during compaction. The binder system is anticipated to have an influence on the grain growth and microstructure which in turn affect the electrical performance. To investigate this phenomenon, TiO2 powder doped with tungsten oxide (WO3), silicon oxide (SiO2) and bismuth oxide (Bi2O3) was processed with and without various percent of latex binder. The prepared samples were characterized by evaluating the physical properties like green density, fired density, axial and radial shrinkage, micro hardness and compressive strength. It was observed that TiO2 processed with latex binder exhibited higher green density and less axial and radial shrinkage compared to powder processed without binder. However, the binder level did not have any significant influence on the other characteristics of varistor discs. SEM analysis indicated that the average grain size was also influenced by the percent of binder used and but the higher average grain size was obtained for discs without any binder.

Investigation of Low Voltage Varistor Using TiO2 as Base Material and SiO2, Bi2O3 and WO3 as Dopants

2015 ◽  
Vol 1115 ◽  
pp. 156-159
Author(s):  
Shahida Begum ◽  
Zarrin Kothadapani ◽  
Mokanaraju K. Selvaraj ◽  
Mohamed Muntasir
Keyword(s):  
Electrical Properties ◽  
Breakdown Voltage ◽  
Power Loss ◽  
Mechanical Characterization ◽  
Low Voltage ◽  
Base Material ◽  
The Other ◽  
Linear Coefficient ◽  
Radial Shrinkage ◽  
Non Linear

Varistor with TiO2 as the base and SiO2, WO3 and Bi2O3 as dopants were investigated to create a low voltage varistor. The physical, mechanical, microstructural and electrical properties were studied where the concentration of SiO2 was varied but the concentration of WO3 and Bi2O3 was fixed. Physical and mechanical characterization consisted of green and fired density, axial and radial shrinkage and Vickers Hardness. Electrical evaluation on the other hand consisted of non-linear coefficient, breakdown voltage, power loss and clamping ratio. Non-linear coefficient of 2.16, very low breakdown voltage of 5.538V/cm and minimal power loss of 0.0124mW was achieved. It was found that optimum results were achieved with 98.3% TiO2, 0.7% SiO2, 0.5%Bi2O3 and 0.5%WO3.

Hierarchical-structure induced adjustable deformation of super carbon nanotubes with radial shrinkage up to 66%

Carbon ◽  
2017 ◽  
Vol 125 ◽  
pp. 289-298 ◽  
Author(s):  
Xian Shi ◽  
Xiaoqiao He ◽  
Lifeng Wang ◽  
Ligang Sun
Keyword(s):  
Carbon Nanotubes ◽  
Hierarchical Structure ◽  
Radial Shrinkage
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