scholarly journals Filament formation via the instability of a stretching viscous sheet: Physical mechanism, linear theory, and fiber applications

2019 ◽  
Vol 4 (7) ◽  
Author(s):  
Bingrui Xu ◽  
Minhao Li ◽  
Feng Wang ◽  
Steven G. Johnson ◽  
Yoel Fink ◽  
...  
Keyword(s):  
Linear Theory ◽  
Physical Mechanism ◽  
Filament Formation

Time Dependances of the Resistance Coefficients of Polymeric Materials

INEOS OPEN ◽  
2020 ◽  
Vol 3 ◽  
Author(s):  
A. V. Matseevich ◽  
◽  
A. A. Askadskii ◽  
Keyword(s):  
Time Dependence ◽  
Physical Mechanism ◽  
Polymeric Materials ◽  
Resistance Coefficient ◽  
Constant Stress ◽  
Time To Rupture ◽  
Structure Sensitive ◽  
Material Durability ◽  
Resistance Coefficients ◽  
Extremal Character

One of the possible approaches to the analysis of a physical mechanism of time dependence for the resistance coefficients of materials is suggested. The material durability at the constant stress is described using the Zhurkov and Gul' equations and the durability at the alternating stress—using the Bailey criterion. The low strains lead to structuring of a material that is reflected in a reduction of the structure-sensitive coefficient in these equations. This affords 20% increase in the durability. The dependence of the resistance coefficient assumes an extremal character; the maximum is observed at the time to rupture lg tr ≈ 2 (s).

On the linear theory of waves in media with periodic structures

1991 ◽  
Vol 161 (9) ◽  
pp. 201-209 ◽  
Author(s):  
Polina S. Landa ◽  
V.F. Marchenko
Keyword(s):  
Linear Theory ◽  
Periodic Structures

Conductive Filament Formation in Printed Circuit Boards – Effects of Reflow Conditions and Flame Retardants

2009 ◽  
Author(s):  
Bhanu Sood ◽  
Michael Pecht
Keyword(s):  
Flame Retardants ◽  
Printed Circuit Boards ◽  
Electrochemical Process ◽  
Lead Free ◽  
Circuit Boards ◽  
Filament Formation ◽  
Conductive Filament ◽  
Printed Circuit ◽  
Free Solder ◽  
Halogen Free

Abstract Failures in printed circuit boards account for a significant percentage of field returns in electronic products and systems. Conductive filament formation is an electrochemical process that requires the transport of a metal through or across a nonmetallic medium under the influence of an applied electric field. With the advent of lead-free initiatives, boards are being exposed to higher temperatures during lead-free solder processing. This can weaken the glass-fiber bonding, thus enhancing conductive filament formation. The effect of the inclusion of halogen-free flame retardants on conductive filament formation in printed circuit boards is also not completely understood. Previous studies, along with analysis and examinations conducted on printed circuit boards with failure sites that were due to conductive filament formation, have shown that the conductive path is typically formed along the delaminated fiber glass and epoxy resin interfaces. This paper is a result of a year-long study on the effects of reflow temperatures, halogen-free flame retardants, glass reinforcement weave style, and conductor spacing on times to failure due to conductive filament formation.

A method to design beam-splitters based on vectorial theory and discussion on its physical mechanism

2015 ◽  
Vol 32 (2) ◽  
pp. 172
Author(s):  
Haixuan Huang ◽  
Ping Xu ◽  
Shuangchen Ruan ◽  
Tuo Yang ◽  
Xia Yuan ◽  
...  
Keyword(s):  
Physical Mechanism ◽  
Beam Splitters
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