Effect of fiber suspension jet stability on alignment quality of discontinuous carbon fiber tapes

Among advanced cutting methods, High Speed Milling (HSM) is often recommended to improve the productivity and to reduce the costs of machining parts. As every cutting process, HSM is characterized by some defects like surface roughness and delamination are the main defects generated in composite materials. The aim of this experimental work is the studying of the machining quality of woven Carbon fiber reinforced plastics (CFRP) using the HSM technology. Experiments were done using different machining parameters combinations to make opened holes in CFRP laminates. This study investigated the effect of cutting speed, orbital feed speed, hole diameter on the delamination defect and surface roughness responses generated in the drilled holes. The design of experimental tests was generated using the approach of Central Composite Design (CCD). The characterization of these responses was treated with the Analysis of variance (ANOVA) and Response surface methodology (RSM). Results showed that the surface roughness is highly affected by the orbital feed speed (F) with contribution of 22.45%. The delamination factor at entry and exit of holes is strongly influenced by the hole diameter D (25.97% and 57.43%) respectively. The developed model equations gave a good correlation between the empirical and predicted results. The optimization of the milling parameters was treated using desirability function to minimize the surface roughness (Ra) and the delamination factor simultaneously.

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Qualitätssteigerung von Bohrungen in Faserkunststoffverbunden*/Increased quality of bores in fiber reinforced polymers

wt Werkstattstechnik online ◽

10.37544/1436-4980-2015-07-08-59 ◽

2015 ◽

Vol 105 (07-08) ◽

pp. 501-507

Author(s):

L. Heberger ◽

S. Nissle ◽

M. Gurka ◽

B. Kirsch ◽

J. C. Aurich

Keyword(s):

Carbon Fiber ◽

Computer Tomography ◽

Drill Hole ◽

Fiber Reinforced Polymers ◽

Fiber Reinforced ◽

Hole Quality ◽

Carbon Fiber Reinforced Polymers ◽

Reinforced Polymers ◽

Carbon Fiber Reinforced

Beim Bohren von kohlefaserverstärktem Kunststoff treten verstärkt Schädigungen wie Delaminationen und Faserüberstände auf. Mit dem Ziel die Bohrlochqualität zu verbessern, wurde der Einfluss der Werkstückeinspannung hinsichtlich Einspanngeometrie, -kraft und -material untersucht. Zusätzlich zur konventionellen optischen Delaminationsmessung wurde die äußere und die innere Delamination mittels Mikrocomputertomografie analysiert. Durch eine Optimierung der Einspannung konnte die Bohrlochqualität gesteigert werden.   When drilling carbon fiber reinforced polymers damages like delamination and fiber protrusion appear. Aiming to improve the drill hole quality, the influence of the fastening device with respect to fastening geometry, force and material is analyzed. In addition to the conventional optical delamination measurement, the outer and inner delamination is investigated by micro computer tomography. The optimization of the fastening device leads to a higher drill hole quality.

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THRUST FORCE PREDICTION MODEL FOR DRILLING UNIDIRECTIONAL CARBON PLASTICS WITH WEAR OF THE CUTTING TOOL

Fundamental and Applied Problems of Engineering and Technology ◽

10.33979/2073-7408-2021-346-2-100-108 ◽

2021 ◽

Vol 2 ◽

pp. 100-108

Author(s):

V.I. GOLOVIN ◽

S.YU. RADCHENKO

Keyword(s):

Carbon Fiber ◽

Tool Wear ◽

Prediction Model ◽

Cutting Tool ◽

Thrust Force ◽

Contact Conditions ◽

Force Prediction ◽

Geometric Characteristics ◽

Drill Tool

One of the most important tasks in the production of carbon fiber products is to ensure the specified accuracy and quality of the drilled holes. A model for predicting the thrust force, taking into account the degree of tool wear, is proposed. First, the geometric characteristics of the wear of the spiral drill tool are analyzed. Further, the contact conditions between the drill and the carbon fiber are determined in accordance with the geometric characteristics of the tool wear. Based on the mechanics of the contact interaction of surfaces, the thrust forces of the main cutting edges and the chisel edge are modeled, taking into account the degree of tool wear. The results obtained are integrated into the thrust force prediction model. An example of an experimental study of the drilling carbon fiber is given. The results obtained show a fairly accurate prediction of the cutting force, taking into account the wear of the cutting tool.

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The concept of biaxial surface potential and polymer aligning layers in electro-optical cells based on helical nanostructures of ferroelectric liquid crystal

Journal of Physics Conference Series ◽

10.1088/1742-6596/2056/1/012044 ◽

2021 ◽

Vol 2056 (1) ◽

pp. 012044

Author(s):

T P Tkachenko ◽

A A Zhukov ◽

E P Pozhidaev

Keyword(s):

Liquid Crystal ◽

Liquid Crystals ◽

Surface Potential ◽

Ferroelectric Liquid Crystal ◽

Alignment Quality ◽

Ferroelectric Liquid Crystals ◽

Helical Pitch

Abstract The paper considers the possibility of controlling the alignment quality of helical nanostructures of ferroelectric liquid crystals (FLCs) within the concept of biaxial surface potential due to variation the FLCs helical pitch p0 and polymer aligning layers structures.

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Carbon Fiber Production from Electrospun Sulfur Free Softwood Lignin Precursors

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501701200405 ◽

2017 ◽

Vol 12 (4) ◽

pp. 155892501701200 ◽

Cited By ~ 5

Author(s):

Samira Aslanzadeh ◽

Behzad Ahvazi ◽

Yaman Boluk ◽

Cagri Ayranci

Keyword(s):

Carbon Fiber ◽

Carbon Fibers ◽

Structural Characteristics ◽

Morphological Characteristics ◽

Carbonization Temperature ◽

Purification Process ◽

Fiber Morphology ◽

Heating Rates ◽

Fiber Production

In this study, a sulfur-free softwood lignin (SFSL) was electrospun to form bead-free fibers. The fibers were evaluated as potential precursors for carbon fiber production. Higher heating rates of thermostabilization caused afused fiber morphology. The lignin purification process also affected the quality of the SFSL-based carbon fibers. Therefore, the yield, morphological characteristics, structural characteristics, electrical conductivity and mechanical properties of the carbon fibers were evaluated. At higher carbonization temperatures crystalline carbon fibers were formed. As a result, as the carbonization temperature increased, the conductivity of SFSL-based carbon fibers also increased.

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