TRIVAL ANTENE - Professional Military Antennas and Antenna Masts

COMPOSITE MATERIALS ( winding and pultrusion)

Winding

Wound composites are manufactured by Filament Winding process. FW is a wet technology for setting fibre rein- forcements with the help of numericalcontrol (CNC) machines which at the same time enable designing (the calculations of optimalforms) and extreme precision of composite structure and thus guarantee high
quality. With optimal roving position, proportion, fibre selection and suitable resin we obtain:

- high mechanical properties
- pressure resistance (inner and outer)
- big torsion stability
- temperature stability
- high electric and thermal resistance

- small thermal expansion coefficient
- corrosion resistance
- low specific density
- electric conductivity
- good sound isolation

The table of tube profile properties made of epoxy resin reinforced by EC glass fibres; thickness 3 mm
(measurements done at 200 C and relative moisture 65 %).

PROPERTIES	UNIT	VALUE
Volume density	kg/m3	< 2000
Water absorbtion (thickness 10mm: 24h in water)	%	0.025
Elasticity module	Gpa	35
Axial tension strength	Gpa	0.35
Radial tension strength	Gpa	0.75
Compressive strength parallel with layers	Gpa	0.23
Compressive strength rectangular on layers	Gpa	0.81
Bending strength (flat test specimen)	Gpa	0.26
Electric strength (rectangular on layers; thickness 3mm, 20 oC in oil)	kV/5 min	40
Electric strength (parallel with layers 20 oC in oil)	kV/5 min	40
Dielectric constant at 50 Hz - 2kV mm		5.35
Dielectric constant at 1 MHz		4.35
Power loss factor (tg delta) at 50 Hz		<0.01
Power loss factor (tg delta) at 1 MHz		<0.01
Pipe surface resistance	M ohm	1.00E+08
Specific resistance	M ohm	1.00E+08
Surface leakage resistance (IEC 122)	V	600
Temperature class	o C	F(155 oC)

Pultrusion

The technology of pultrusion enables the production of profiles different in forms and dimensions, from simple round and rectangular to hollow, bent or any other special cross-sections, and it guarantees constant high quality and dimensional stability within close tolerances. Different resins, different fibre reinforcement types and their arrangements can be adapted to suit specific requirements in individual application. With extra pull winding section it is possible to manufacture tubes and hollow profiles which have a part of fibres in tangential direction. With incorporation of reinforcements which have fibres oriented also in transversal direction the mechanical properties in this direction are significantly better.
Composite materials are anisotropic. Properties differ in different directions. General characteristics of Trivapul profiles depend on the structure and construction of the composite and also on the direction. That is why for instance mechanical properties in direction parallel to fibres are much better than in direction rectangular to fibres. In the table below the approximate values of uni directional Trivapul profile properties are listed. Mechanical properties in direction parallel to fibres are of higher values and mechanical properties in transversal direction are of lower values.

PHYSICAL PROPERTIES

	UNIT	VALUE	STANDARD
Density	kg/m3	1.6 - 2.2	DIN53479	ISO 1183
Glassfiber content	vol%	40 - 70
Thermal coeff. of expansion	1/K	..10E5
Thermal conductivity	W/mK	..0.3	DIN52612
Water absorbtion	%	<2	DIN53472	ISO 62
HDT	o C	150 - 220	DIN53461

MECHANICAL PROPERTIES

	UNIT	VALUE	STANDARD
Tensile strength	Gpa	0.02 - 1.0	DIN53455
Jungs modulus	GPa	4 - 50	DIN53457
Elongation at rupture	%	..2	DIN53455
Compression strength	Gpa	0,05 - 0.5	DIN53454
Flexural strength	Gpa	0.02 - 0.9	DIN53452
Impact strength	kJ/m2	50 - 150	DIN53453

ELECTRICAL PROPERTIES

	UNIT	VALUE	STANDARD
Specific resistance	ohm cm	10E10 - 10E15	DIN53482
High voltage break down	kV/mm	5 - 30	DIN53481
Dielectric constant		4 - 6	DIN53483
Loss factor (tg delta)		0.01 - 0.05	DIN53483
Temperature class	o C	130(B)-155(F)-180(H)	VDE 0304	IEC 85