The Influence of Sliding Velocity on the Wear Intensity in Case of Polymeric Composite Materials Reinforced with Short Carbon Fibers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1036.9 ◽

2014 ◽

Vol 1036 ◽

pp. 9-12

Author(s):

Radu Caliman

Keyword(s):

Composite Materials ◽

Friction Coefficient ◽

Carbon Fibers ◽

High Resistance ◽

Research Work ◽

Polymeric Composite ◽

Tantalum Carbide ◽

Sliding Velocity ◽

Polymeric Composite Materials ◽

Short Carbon

This paper presents a study of the tribological properties of polymeric composite materials reinforced with short carbon fibers. Reinforces carbon fibers materials are more effective if refer to specific properties per unit volume compared to conventional isotropic materials. Potential benefits of carbon fibers composite materials are: high resistance to breakage and high value ratios strength/density; resistance to high temperatures; low density and high resistance to wear; low or high friction coefficient. The composites are complex and versatile materials; their versatility it is given by the multitude of choice variety of the constituent materials that can be combined to obtain the desired properties of otherwise unobtainable from conventional materials. The composite materials used in this research work are obtained combining epoxy with short carbon fibers with titanium carbide and tantalum carbide in order to investigate the variation of the friction coefficient for three different sliding velocities. Varying the percent of epoxy from 29,35% to 43,92% and the percent of short carbon fibers from 35,43% to 53,70%, nine different composite materials are obtained and tested. Friction tests are carried out, at room temperature, in dry conditions, on a pin-on-disc machine. The friction coefficient was measured maintaining constant the pressing force (8 daN) and sliding time (120 sec), and varying the sliding velocity to 8, 14 and 23 m/sec. The main objective of this research work it was to identify a composite material with higher friction coefficient.

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Studies Regarding the Influence of Loading Force on the Wear Intensity in Case of Polymeric Composite Materials Reinforced with Short Carbon Fibers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1036.36 ◽

2014 ◽

Vol 1036 ◽

pp. 36-39

Author(s):

Radu Caliman

Keyword(s):

Composite Materials ◽

Carbon Fibers ◽

Research Work ◽

Polymeric Composite ◽

Wear Intensity ◽

Tantalum Carbide ◽

Carbon Fibres ◽

Polymeric Composite Materials ◽

Pin On Disc ◽

Short Carbon

This paper presents a study of the wearing behaviour of polymeric composite materials reinforced with short carbon fibres. Reinforces carbon fiber materials are more effective if refer to specific properties per unit volume compared to conventional isotropic materials. The composite materials used in this research work are obtained combining epoxy with short carbon fibres with titanium carbide and tantalum carbide in order to investigate the wearing intensity of the obtained composites. Varying the percent of epoxy from 29,35% to 43,92% and the percent of short carbon fibres from 35,43% to 53,70%, two different composite materials are obtained and tested. Wearing intensity tests are carried out, at room temperature, in dry conditions, on a pin-on-disc machine. The friction coefficient was measured maintaining constant the rotational speed (14 m/s) and time (120s) and varying the pin-on-disc pressing force: 4, 8 and 12 daN. The pressing load had different effects on the wearing behaviour of the composite coating in dry friction condition. With low percent of epoxy and high percent of carbon fibers the wearing intensity is touching the highest value and gradually decreases with the increasing load, while in low percent of carbon fibers the wearing intensity became larger gradually along with the load increasing.

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Tribological Study in Case of Polymeric Composite Materials Reinforced with Unidirectional Carbon Fibers Having Stratified Structure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.657.422 ◽

2014 ◽

Vol 657 ◽

pp. 422-426

Author(s):

Radu Caliman

Keyword(s):

Composite Materials ◽

Friction Coefficient ◽

Carbon Fibers ◽

High Resistance ◽

Research Work ◽

Polymeric Composite ◽

Wear Properties ◽

Normal Contact ◽

Polymeric Composite Materials ◽

Stratified Structure

This paper presents a study of the tribological properties of polymeric composite materials reinforced with unidirectional carbon fibers having stratified structure. Unidirectional reinforces carbon fiber materials are more effective if refer to specific properties per unit volume compared to conventional isotropic materials [. Potential benefits of carbon fibers composite materials are: high resistance to breakage and high value ratios strength/density; resistance to high temperatures; low density and high resistance to wear; low or high friction coefficient. The composites are complex and versatile materials but their behaviour in practice is not fully studied. For instance, polymeric composite materials reinforced with carbon fibers after being investigated in terms of wear, did not elucidate the effect of fiber orientation on wear properties [. Is therefore necessary to investigate the effect of carbon fibers orientation on the friction wear properties of the reinforced composite materials tested to adhesive and abrasive wear. Research work has been done with unidirectional composite materials having overlap 16 successive layers made from a polymeric resin and 60% of carbon fibers. The stratified structure was obtained by compressing multiple pre-impregnated strips, positioned manually. During this experimental work, three types of test samples were investigated: normal, parallel and anti-parallel, taking in consideration the carbon fibre orientation with respect to the sliding direction. The specific wear rate was calculated according to: the mass loss, density, the normal contact surface, the sliding distance and load rating. The friction coefficient is computed function to the friction load and loading value.

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Friction and Wearing Behaviour of Sintered Composites Made from Copper Mixed with Carbon Fibers

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.660.81 ◽

2015 ◽

Vol 660 ◽

pp. 81-85 ◽

Cited By ~ 1

Author(s):

Radu Caliman

Keyword(s):

Thermal Conductivity ◽

Thermal Expansion ◽

Composite Materials ◽

Friction Coefficient ◽

Carbon Fiber ◽

Carbon Fibers ◽

Coefficient Of Thermal Expansion ◽

Density Ratio ◽

Point Of View ◽

Short Carbon

This paper presents a study regarding friction and wear comportment of sintered composite materials obtained by mixture of copper with short carbon fibers. Sintered composites are gaining importance because the reinforcement serves to reduce the coefficient of thermal expansion and increase the strength and modulus. In case of composites form by carbon fiber and copper, the thermal conductivity can also be enhanced. The combination of low thermal expansion and high thermal conductivity makes them very attractive for electronic packaging. Besides good thermal properties, their low density makes them particularly desirable for aerospace electronics and orbiting space structures. Compared to the metal itself, a carbon fiber-copper composite is characterized by a higher strength-to-density ratio, a higher modulus-to-density ratio, better fatigue resistance, better high-temperature mechanical properties and better wear resistance. Varying the percentage of short carbon fibers from 7,8% to 2,4%, and the percentage of copper from 92,2% to 97,6%, five dissimilar composite materials have been made and tested from the wear point of view. Friction tests are carried out, at room temperature, in dry conditions, on a pin-on-disc machine. The friction coefficient was measured using abrasive discs made from steel 4340 having the average hardness of 40 HRC, and sliding velocity of 0,6 m/sec. The primary goal of this study work it was to distinguish a mixture of materials with enhanced friction and wearing behaviour. The load applied on the specimen during the tests, is playing a very important role regarding friction coefficient and also the wearing speed.

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