Frequency-Doubling In Glass Fibers

1988 ◽  
Author(s):  
Walter Margulis ◽  
Ulf Osterberg
Keyword(s):  
Glass Fibers ◽  
Frequency Doubling

Failure Localization of Intermittent Short Failures Caused by Vertical Conductive Anodic Filament Formation

2014 ◽  
Author(s):  
Daniel Nuez ◽  
Phoumra Tan
Keyword(s):  
Glass Fibers ◽  
Vertical Plane ◽  
Axis Formation ◽  
Metal Trace ◽  
Conductive Anodic Filament ◽  
Plated Through Hole ◽  
Voltage Gradients ◽  
Ic Package ◽  
Through Hole ◽  
Failure Localization

Abstract Conductive anodic filament (CAF) formation is a mechanism caused by an electrochemical migration of metals from a metal trace in ICs or in PCBs. This is commonly caused by the moisture build-up in the affected metal terminals in an IC package or PC board caused by critical temperature, high humidity and high voltage gradients conditions. This phenomenon is known to have caused catastrophic field failures on various OEMs electronic components in the past [1,7]. Most published articles on CAF described the formation of the filament in a lateral formation through the glass fiber interfaces between two adjacent metal planes [1-6, 8-12]. One common example is the CAF formation seen between PTH (Plated through Hole) in the laminated substrate with two different potentials causing shorts [1-6, 8-12]. In this paper, the Cu filament grows in a vertical fashion (z-axis formation) creating a vertical plane shorts between the upper and lower metal terminals in a laminated IC package substrate. The copper growth migration does not follow the fiber strands laterally or vertically through them. Instead, it grows through the stress created gaps between the impregnated carbon epoxy fillers from the upper metal trace to the lower metal trace with two different potentials, between the glass fibers. This vertical CAF mechanism creates a low resistive short that was sometimes found to be intermittent in nature. This paper presents some successful failure analysis approaches used to isolate and detect the failure locations for this type of failing devices. This paper also exposes the unique physical appearance of the vertical CAF formation.

3.0 W blue light generation by frequency doubling of broad area semiconductor amplifier emission

1993 ◽  
Vol 29 (1) ◽  
pp. 77-78 ◽  
Author(s):  
L.E. Busse ◽  
L. Goldberg ◽  
D. Mehuys ◽  
G. Mizell
Keyword(s):  
Blue Light ◽  
Frequency Doubling ◽  
Broad Area ◽  
Light Generation

Correlation of fatigue behavior and dynamic mechanical properties of hybrid composites of polypropylene/short glass fibers/hollow glass beads

2021 ◽  
pp. 089270572199319
Author(s):  
Gustavo B Carvalho
Keyword(s):  
Stress Relaxation ◽  
Flexural Strength ◽  
Relaxation Rate ◽  
Hybrid Composites ◽  
Fatigue Behavior ◽  
Glass Fibers ◽  
Glass Beads ◽  
Hollow Glass ◽  
Dynamic Mechanical ◽  
Short Glass

Ternary hybrid composites of Polypropylene (PP)/Short Glass Fibers (GF)/Hollow Glass Beads (HGB) were prepared using untreated and aminosilane-treated HGB, compatibilized with maleated-PP, and with varying total and relative GF/HGB contents. Static/short-term flexural strength properties data revealed, through lower flexural strength values, that the presence of untreated HGB particles induces to fiber-polymer interfacial decoupling at much higher extent than in the presence of aminosilane-treated HGB particles. This phenomenon is also evident when evaluating the data from displacement-controlled three-point bending fatigue tests. Monitored up to 106 cycles, the analyzed hybrid composites presented distinct performance relative to their fatigue stress relaxation rate: the lower the matrix-reinforcements’ interfacial adhesion, more pronounced the stress relaxation rate as a function of the number of fatigue cycles. Dynamic Mechanical Thermal Analysis (DMTA) results could successfully reveal the hybrid composites behavior at the microstructural level when they were submitted to both static flexural test and fatigue, depending on the degree of interfacial interactions between the polymer matrix of PP and the hybrid reinforcements of GF and HGB (with and without aminosilane surface treatment).

scholarly journals Effects of Microwave Treatment in Immersed Conditions on the Mechanical Properties of Jute Yarn

Fibers ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 40
Author(s):  
Felicia Syrén ◽  
Joel Peterson ◽  
Nawar Kadi
Keyword(s):  
Mechanical Properties ◽  
Tensile Testing ◽  
Glass Fibers ◽  
Microwave Treatment ◽  
Environmental Benefits ◽  
Treatment Result ◽  
Bast Fiber ◽  
Fiber Properties ◽  
Yarn Thickness ◽  
Jute Yarn

The versatile bast fiber jute has environmental benefits compared to glass fibers. However, for jute to be used in a composite, the fiber properties need to be altered. This study aims to improve the mechanical properties of jute yarn to make it more suitable for technical applications as a composite. To alter its mechanical properties, jute yarn was immersed in water during microwave treatment. The time and power of the microwave settings differed between runs. Two states of the yarn were tested: fastened and un-fastened. Tensile testing was used at the yarn and fiber level, followed by Fourier-transform infrared spectroscopy (FTIR) and microscopy. The treatment result demonstrated the ability to increase the elongation of the jute yarn by 70%. The tenacity was also increased by 34% in the fastened state and 20% in the un-fastened state. FTIR showed that no change in the molecular structure occurred. The treatments resulted in a change of yarn thickness depending on the state of the yarn. The results indicate that microwave treatment can be used to make jute more suitable for technical applications depending on the microwave treatment parameters.

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