Experimental simulation of bending damage of silicon nitride yarn during 3D orthogonal fabric forming process

2021 ◽  
pp. 152808372110106
Author(s):  
Ning Wu ◽  
Shuai Li ◽  
Meiyue Han ◽  
Chao Zhu ◽  
Yanan Jiao ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Silicon Nitride ◽  
Strength Loss ◽  
Fracture Probability ◽  
Experimental Simulation ◽  
Fracture Mechanisms ◽  
Forming Process ◽  
Yarn Tension ◽  
Fabric Thickness ◽  
Bending Fracture

The aim of this study executed on Silicon Nitride (Si3N4) yarn is to examine some bending damage behaviors and fracture mechanisms that occur during the 3D orthogonal fabric forming process. A three point bending experiment device has been developed in order to simulate the Z-binder yarn bending condition. The effects of weft density, fabric thickness, and yarn tension have been studied. The Weibull analysis of the tensile strength show that the bending damage increases with the increase of weft density, fabric thickness, and yarn tension. The resulting bending damage causes a reduction in yarn strength of between 2.5 and 17.2% depending on the bending parameters of yarn. The growth of the fibrillation area also reflects similar trends with tensile strength loss rate. The fibrillation length produced by the yarns is mostly distributed within the range of 0.3 to 0.9 mm. A comparison of the calculation result to experimental data shows the bending fracture probability of filaments inside yarn are less than that of monofilament. The tensile and bending fracture of Si3N4 filaments exhibit typical brittle fracture characteristics.

Upscaling of foam forming technology for pilot scale

TAPPI Journal ◽  
2019 ◽  
Vol 18 (8) ◽  
Author(s):  
JANI LEHMONEN ◽  
TIMO RANTANEN ◽  
KARITA KINNUNEN-RAUDASKOSKI
Keyword(s):  
Production Efficiency ◽  
Strength Loss ◽  
Pilot Scale ◽  
Foam Density ◽  
Forming Process ◽  
Production Scale ◽  
Forming Technology ◽  
Wet Pressing ◽  
Foam Forming ◽  
Board Industry

The need for production cost savings and changes in the global paper and board industry during recent years have been constants. Changes in the global paper and board industry during past years have increased the need for more cost-efficient processes and production technologies. It is known that in paper and board production, foam typically leads to problems in the process rather than improvements in production efficiency. Foam forming technology, where foam is used as a carrier phase and a flowing medium, exploits the properties of dispersive foam. In this study, the possibility of applying foam forming technology to paper applications was investigated using a pilot scale paper forming environment modified for foam forming from conventional water forming. According to the results, the shape of jet-to-wire ratios was the same in both forming methods, but in the case of foam forming, the achieved scale of jet-to-wire ratio and MD/CD-ratio were wider and not behaving sensitively to shear changes in the forming section as a water forming process would. This kind of behavior would be beneficial when upscaling foam technology to the production scale. The dryness results after the forming section indicated the improvement in dewatering, especially when foam density was at the lowest level (i.e., air content was at the highest level). In addition, the dryness results after the pressing section indicated a faster increase in the dryness level as a function of foam density, with all density levels compared to the corresponding water formed sheets. According to the study, the bonding level of water- and foam-laid structures were at the same level when the highest wet pressing value was applied. The results of the study show that the strength loss often associated with foam forming can be compensated for successfully through wet pressing.

scholarly journals Tensile Strength of Nylon Netting Subjected to Various Concentrations of Disinfecting Chemicals

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Heidi Moe Føre ◽  
Stine Wiborg Dahle ◽  
Rune H. Gaarder
Keyword(s):  
Hydrogen Peroxide ◽  
Tensile Strength ◽  
Fish Farming ◽  
Strength Loss ◽  
Chemical Exposure ◽  
Strength Reduction ◽  
Severe Reduction ◽  
Service Stations ◽  
Trade Names ◽  
Net Cages

This paper presents a study of traditional netting materials subjected to disinfecting chemicals during fish farming and treatment of net cages. A series of tests were performed in order to study the effect of various concentrations of disinfecting chemicals on the tensile strength of Raschel knitted Nylon netting materials. Simulated spill of diluted hydrogen peroxide (HP) to the jump fence during de-lousing did not affect the strength of the applied new and used knotless nylon netting samples. Hydrogen peroxide reacted with biofouling forming gas bubbles, but this did not result in reduced netting strength. The performed tests did not indicate any effect on netting strength from a simulated single, traditional bath disinfection as performed at service stations applying the disinfectant Aqua Des (AD) containing peracetic acid (PAA). However, increasing the AD concentration from 1 to 10% resulted in a strength reduction of 3–6%. Simulated spill of concentrated AD on the jump fence of a net with copper coating residuals resulted in a severe reduction in strength of 45%. This strength loss was probably a consequence of chemical reaction between copper and Aqua Des, and uncoated netting did not experience any loss in strength subjected to the same chemical exposure. These findings from application of AD should also apply to other PAA disinfection chemicals with trade names as, for example, Perfectoxid and Addi Aqua.

Anab initiocalculation of the ideal tensile strength of β-silicon nitride

2001 ◽  
Vol 64 (17) ◽  
Author(s):  
Shigenobu Ogata ◽  
Naoto Hirosaki ◽  
Cenk Kocer ◽  
Hiroshi Kitagawa
Keyword(s):  
Tensile Strength ◽  
Silicon Nitride ◽  
The Ideal

scholarly journals Tensile Strength of Hot Isostatic Pressed Silicon Nitride and Effect of Specimen Dimension.

1991 ◽  
Vol 57 (539) ◽  
pp. 1637-1642 ◽  
Author(s):  
Shoji HARADA ◽  
Nao-Aki NODA ◽  
Osamu UEHARA ◽  
Mitsuyoshi NAGANO
Keyword(s):  
Tensile Strength ◽  
Silicon Nitride ◽  
Specimen Dimension

scholarly journals Experiment on Foreign Object Damage of Gas Turbine-Grade Silicon Nitride Ceramic

1998 ◽  
Author(s):  
Hiro Yoshida ◽  
Takashi Nakashima ◽  
Makoto Yoshida ◽  
Yasushi Hara ◽  
Toru Shimamori
Keyword(s):  
Elevated Temperature ◽  
Silicon Nitride ◽  
Elevated Temperatures ◽  
Tensile Load ◽  
Strength Degradation ◽  
Spall Fracture ◽  
Silicon Nitride Ceramic ◽  
Impact Tests ◽  
The Impact ◽  
Bending Fracture

A new high quality turbine system using monolithic silicon-nitride ceramic is under development. In this study particle impact tests of the silicon-nitride have been tried at room and elevated temperatures with and without tensile load, which simulates centrifugal force of blade rotation. In the experiment 1 mm diameter particle is impacted at velocities up to 900 m s−1. In this paper, critical velocities for bending fracture and Hertzian cracks are examined. Moreover, strength degradation at elevated temperature and spall fracture of the blade are discussed. The main results are: 1) The bending fracture mode critical impact velocity for soft particles is higher than that for hard particles. 2)The impact parameter ϕ for initiation of Hertzian cracks ranges 1.08×10−5 – 1.56×10−5 for the materials tested. 3)Strength degradation at elevated temperature was clearly observed. 4) In the impact tests on blades spall fracture, which was caused by interaction of stress waves, appeared.

scholarly journals New Enzyme-based Process Direction to Prevent Wool Shrinking without Substantial Tensile Strength Loss

2006 ◽  
Vol 28 (10) ◽  
pp. 711-716 ◽  
Author(s):  
H. B. M. Lenting ◽  
M. Schroeder ◽  
G. M. Guebitz ◽  
A. Cavaco-Paulo ◽  
J. Shen
Keyword(s):  
Tensile Strength ◽  
Strength Loss

scholarly journals Investigation of Atmospheric Moisture during Heat Treatment of Glass Fibres

Fibers ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 27 ◽  
Author(s):  
Peter Jenkins ◽  
Liu Yang ◽  
James Thomason
Keyword(s):  
Heat Treatment ◽  
Tensile Strength ◽  
Elevated Temperature ◽  
Glass Fibre ◽  
Room Temperature ◽  
Strength Loss ◽  
Fibre Strength ◽  
Atmospheric Moisture ◽  
Glass Fibres ◽  
Alternative Theories

The tensile strength of single water-sized E-glass fibres that were thermally conditioned, either in air or under vacuum, was investigated. The vacuum removed water from the conditioning atmosphere, as well as the fibre surfaces, at room temperature but retained tensile strength of fibres treated in the absence of water were not significantly different from those thermally conditioned in a standard air furnace. The results suggest that water, either in the treatment atmosphere or on the surface of the fibres, is not a significant factor in fundamental glass fibre strength loss at an elevated temperature. It may, therefore, be necessary to consider alternative theories to explain this strength loss.

Effect of Heat Treatment on Tensile Strength and Microstructure of AZ61A Magnesium Alloy

2014 ◽  
Vol 606 ◽  
pp. 55-59 ◽  
Author(s):  
R. Senthil ◽  
A. Gnanavelbabu
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Magnesium Alloy ◽  
Magnesium Alloys ◽  
Mg Alloys ◽  
Forming Process ◽  
Microstructural Parameters ◽  
Heat Treated ◽  
Mutual Relations

Magnesium alloys are the very progressive materials whereon is due to improve their end-use properties. Especially, wrought Mg alloys attract attention since they have more advantageous mechanical properties than cast Mg alloys. Investigations were carried out the effects of heat treatment on tensile strength and microstructure of AZ61A magnesium alloy. The AZ61A Mg alloy is solution heat treated at the temperature of 6500F (343°C) for various soaking timing such as 120 min, 240 min and 360 minutes and allowed it cool slowly in the furnace itself. Magnesium alloys usually are heat treated either to improve mechanical properties or as means of conditioning for specific fabrication operations. Special attention had been focused on the analysis of mutual relations existing between the deformation conditions, microstructural parameters, grain size and the achieved mechanical properties. The result after the solution heat treatment, showed remarkably improved hardness, tensile strength and yield strength. It would be appropriate for a forming process namely isostatic forming process.

Tensile strength of handsheets prepared with macerated fibres from solid wood modified with cross-linking agents

Holzforschung ◽  
2015 ◽  
Vol 69 (8) ◽  
pp. 959-966 ◽  
Author(s):  
Stergios Adamopoulos ◽  
Reza Hosseinpourpia ◽  
Carsten Mai
Keyword(s):  
Tensile Strength ◽  
Strength Loss ◽  
Solid Wood ◽  
Cross Linking ◽  
Microscopic Appearance ◽  
Finite Span ◽  
The Stability ◽  
And Control ◽  
Additional Role ◽  
Modified Wood

Abstract This study was conducted to explain the tensile strength loss of wood due to the modification with 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) and glutaraldehyde (GA). Modified and control wood blocks were macerated to deliberate fibres, and handsheets were produced thereof. The nitrogen content of the fibres indicated that maceration removed the major proportions of DMDHEU. The stability of GA in wood during maceration was not assessed. Tensile strength determined at zero span (z-strength) and finite span (f-strength) was equal for the handsheets from DMDHEU-modified fibres and the control handsheets. The microscopic appearance of the tested finite-span paper strips from DMDHEU-modified fibres mainly indicated interfibre failure and did not differ from the fibre fracture mode of the control handsheets. In contrast, the z-strength of the handsheets from GA-modified fibres was lower than that of controls and decreased with increasing content of GA in the initial modified wood. The f-strength behaviour of the handsheets from GA-modified fibres was the opposite: it was higher than that of controls and increased with increasing GA content. The microscopic appearance of the rapture zones of the finite-span testing mainly indicated intrafibre failure for the GA-modified fibres. It was concluded that cross-linking is likely to be the major reason for tensile strength loss of GA- and DMDHEU-modified wood. In terms of DMDHEU-modified wood, the incrustation of the cell wall by the resin and the reduction in pliability could play an additional role.

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