TUFNOL Grade 6F/45 Cotton fabric based epoxy laminate

A top quality epoxy grade combining electrical performance with first class mechanical capabilities

This TUFNOL epoxy cotton grade has a unique combination of properties, which makes it particularly useful for applications requiring extra performance.  It has good all-round performance but its principal features are its excellent electrical properties, good dimensional stability and outstanding machinability. 

Grade 6F/45 is made with a specially modified epoxy resin, which gives it high insulation resistance and electric strength, and an exceptional resistance to surface electrical tracking.  These first class electrical properties, with the excellent wear resistance of the finer weave cotton, together provide a combination of properties not found in other grades. 

Grade 6F/45 is mechanically strong and is resistant to a wide range of chemicals.  It has low water absorption and good dimensional stability, giving fine tolerances and a superb machined finish.

What is Grade 6F/45 used for?

This versatile grade is used for a very broad range of applications, where precision and a high quality machined finish need to be combined with electrical or mechanical performance.  It is used for rotor blades in compressors, slip ring assemblies in helicopters. Windshield components on commercial aircraft, high vacuum components, slot wedges, coil supports in turbine generators, labyrinth seals, insulating gears in scientific instruments, electrical mounting plates and large electrical terminal blocks.

TYPES AVAILABLE

Sheets

Rods

Tubes

Other sections

Natural colour

Yes

Yes

Yes

Yes*

BRITISH STANDARDS

Current Standards

Recent Standards (now obsolete)

Sheet

BS EN 60893-3-2 Type EP CC 301

BS 2572 Type F6

Round Rod (Rolled & moulded)

BS EN 61212-3-3 Type EP CC 41

Rectangular Bar

BS 6128 Part 4 Type PF CC 41 & 42

(BS 6128 will shortly become obsolete.)

Hexagon Bar

BS 6128 Part 6 Type PF CC 61 & 62

Round Tube

BS EN 61212-3-2 Type EP CC 31

Rectangular Tube

BS 6128 Part 13 Type PF CC 131

PROPERTY

TYPICAL RESULT

UNITS

Cross breaking strength

170

MPa

Impact strength, notched, Charpy

4.6

kJ/m²

Compressive strength, flatwise

290

MPa

Compressive strength, edgewise

190

MPa

Shear strength, flatwise

100

MPa

Water Absorption

- 1.6mm thk.

30

mg

- 3mm thk.

35

mg

- 6mm thk.

45

mg

- 12mm thk.

55

mg

Electric strength, flatwise in oil at 90ºC

- 1.6mm thk.

15

MV/m

- 3mm thk.

12

MV/m

- 6mm thk.

10

MV/m

Electric strength, edgewise in oil at 90ºC

80

kV

Insulation resistance after immersion in water

3x10¹¹

ohms

Loss tangent at 1 MHz

0.040

-

Permittivity at 1 MHz

4.3

-

Comparative tracking index

800

-

Relative density

1.36

-

Maximum working temperature**

- continuous

130

ºC

- intermittent

150

ºC

Thermal classification

Class B

-

Thermal conductivity through laminae

0.36

W/(mK)

Thermal expansion in plane of laminae

1.8

x 10^-5/K

Specific heat

1.5

kJ/(kgK)

PROPERTY

TYPICAL RESULT

UNITS

Axial compressive strength

180

MPa

Cohesion between layers

130

MPa

Water absorption

1.2

mg/cm²

Insulation resistance after immersion in water

1x10¹⁰

ohms

Loss tangent at 1 MHz

0.04

-

Permittivity at 1 MHz

4.0

-

Axial electric strength in oil at 90ºC

75

KV

Radial electric strength in oil at 90ºC

 - 1.6mm wall

13

MV/m

 - 3.0mm wall

10

MV/m

Relative density

1.35

-

PROPERTY

TYPICAL RESULT

UNITS

Flexural strength

170

MPa

Water absorption

1.3

mg/cm²

Insulation resistance after immersion in water

1x10¹⁰

ohms

Axial electric strength in oil at 90ºC

80

kV

Relative density

1.35

-