3M™ Nextel™ Ceramic Textiles and Composites provide innovative solutions in industries from aerospace to petroleum refining to metal processing. The outstanding thermal protection provided by Nextel™ Fabrics, Tapes and Sleevings allows engineers and manufacturers to handle high temperature applications up to 2500°F (1371°C).
Nextel™ Ceramic Fibers 312 and 440, when converted to fabrics, tapes, sleevings, and paper are used in the aerospace, industrial, automotive, electrical and petrochemical markets as heat shields, curtains, linings, insulation, blankets and seals. Nextel™ Flame Stopping Dot Paper, engineered with Nextel™ Fiber 312, is ideal in applications where both flame barrier properties and light weight are critical.

Nextel™ Composite Fibers

The family of 3M™ Nextel™ Fibers was developed to serve a variety of needs. 3M™ Nextel™ Fibers 312, 440, and 550 are designed for non-structural applications where their primary purpose is to insulate or to act as a flame barrier.  To aid in the selection of the proper fiber for each of these different applications, the fibers are tested in a manner appropriate to their end use.

3M™ Nextel™ 440 Ceramic Fiber Typical Properties

Property	Units	Nextel™ 440
Use Temperature	—	2500°F
Filament Diameter	mm
Crystal Size	nm	<500
Crystal Type		gamma Al2O3 + mullite + amorph. SiO2
Density	g/cc	3.05
Filament Tensile Strength (51mm gage)	MPa	2000
Filament Tensile Modulus	GPa	190
Surface Area	m2/g	<.2
Composition	wt%	70 Al2O3 28 SiO2 2 B2O3
Thermal Expansion (100-1100°C)	ppm/°C	5.3
Dielectric Constant	(@ 9.375 Ghz)	5.7

3M™ Nextel™ Roving 440 – Typical Properties

Color: Coral

Roving	Nominal Filament Count	Yield ± 10% yds/lb m/kg		Breaking Load*  lbs kg
700 denier (78 tex)	400	6350	12800	7	3,2
1000 denier (111 tex)	400	4460	8990	9	4,1
2000 denier (222 tex)	750	2230	4490	14	6,4

3M™ Nextel™ Plied Yarn 440 – Typical Properties

Color: Coral

Yarn	Ends	Diameter in mm		Yield ± 10% yds/lb m/kg		Breaking Load* lbs kg
700 denier (78 tex) 2.7 Twists/inch (106 Twists/m)**
1/2	2	0.007	0,18	3000	6050	15	6,9
1/4	4	0.013	0,33	1530	3080	27	12,2
1000 denier (111 tex) 2.7 Twists/inch (106 Twists/m)**
1/2	2	0.01	0,25	2150	4330	20	9,1
2/2	4	0.017	0,43	1070	2160	35	15,9
3/4	12	0.036	0,91	350	710	95	43,1
1800 denier (200 tex) 2.7 Twists/inch (106 Twists/m)**
1/2	2	0.016	0,41	1065	2150	34	15,4
2/5	10	0.047	1,19	210	420	140	63,5

Note:  All yields are based upon sized rovings and yarns.  The allowable range in add-ons for sizing is 1.1 to 3.0% by weight.  The allowable tolerance on final twist is ± 30%.
*  Tested at room temperature.
**  The allowable tolerance on final twist is ± 30%.  Other twist levels available.

3M™ Nextel™ 440 Roving Strength Maximum Temperature Limit

	Roving Strength
Fiber	Maximum
	Temperature Limit
Nextel™ 440

* Strain rate = 12.5 mm/min

Fiber Weight Loss Nextel™ 440 Ceramic Fiber Roving

Roving samples were subjected to 2192°F (1200°C) for fifteen hours. Fibers were weighed before and after the fifteen hour exposure in order to determine weight loss. The fiber evolves B2O3 at temperatures greater than 2012°F (1100°C).

Fiber	Weight Loss %
440	0

Shrinkage on Nextel™ 440 Fiber

Roving samples were held at each temperature for fifteen hours. After that time they were measured for shrinkage. All fiber compositions showed less than three percent shrinkage after fifteen hours at 2372ýF (1300ýC). Nextel™ 440 Fiber compositions showed shrinkage of less than 1.5% at these conditions.

Nextel™ Ceramic Fiber 440 Moisture Absorption

The 3M™ Nextel™ Ceramic Fibers 440 absorb very little moisture due to their smooth, non-porous surface. Fibers exposed to 100% relative humidity for several hours at room temperature had 0.08% weight gain.

Cryogenic Testing on 3M™ Nextel™ Woven Tape 440

Five samples of 3M™ Nextel™ Woven Tape 440 1 inch (2,54 cm) wide were cut to 6 inch (15,2 cm) lengths for testing in liquid nitrogen.

Samples were heat cleaned at 1472 F (800 C) for one hour to remove the sizing before testing.

Samples were placed in liquid nitrogen to soak for three minutes. Samples were then removed and tested for strength retention.

A second set of five samples was dipped into liquid nitrogen ten times and then tested for strength retention.

	Retained Strength
Sample	Soaked 3 Minutes in N2	Dipped 10 Times in N2
3M™ Nextel™ Tape 440	98%	89%

Radiation Resistance & Microwave Measurement - 3M™ Nextel™ Ceramic 440 Radiation Resistance

Exposure to radiation from a Cobalt 60 source did no noticeable damage to the 3M™ Nextel™ Fiber 440. A total of 1 x 107 rads at an exposure rate of 2.1 x 10 5 rads/hour did not change the tensile strength of the fibers, yarns or fabrics made from the fibers.

Microwave Measurements

Power Transmission and Reflection for 3M™ Nextel™ Fabric panels 18 inch x 18 inch (45.7 cm x 45.7 cm) at 10 GHz.

Fabric	Transmission*	Reflection**	Transmission*	Reflection**
Specimen	5	10	5	10
	Layers	Layers	Layers	Layers
AF-30	96.50%	97.80%	7%	0.45%
BF-30	94.70%	96.70%	7%	0.14%

*Sample held with styrofoam panels, angles of incidence 0°.
**Sample uncompressed, angle of incidence 10°. Compared to copper plate with perpendicular polarization.

3M™ Nextel™ Woven Fabric 440 – Thermal Optical Properties*

The optical properties of fibers on the exterior of the space craft controls the amount of solar heating that will occur in orbit. For instance, a low absorptivity would be desired if one were designing components for a spacecraft mission. This would reflect most of the sun’s energy and protect the craft and the instruments from high temperatures.
Optical measurements were made on 3M™ Nextel™ Woven Fabric 440 using a Gler Dunkle DB-100 Emissometer and MS-251 Solar Reflectometer machines. The average absorptance () and emittance () are as follows:

Material	Absorptivity	Emissivity
440	0.15	0.87

NASA Nonmetallic Material Testing*

Flammability, Toxicity and Thermal Vacuum Stability testing on 3M™ Nextel™ Woven Fabrics was performed using procedures specified in NHB 8060.1B and SP-R-0022A.
Flammability: Passed test in 30% oxygen and 10 psia environment.
Toxicity: Passed Test.

Thermal Vacuum Stability: Heat cleaned fabric passed test. Sized 3M™ Nextel™ Fabric outgassed volatile condensable materials of 0.15%, which exceeded the required limit of 0.1 weight %.
*Courtesy-NASA

Back to 3M™ Nextel™ Overview

Further information on 3M™ Nextel™ 440 Ceramic Textiles

• Nextel™ 440 MSDS
• Nextel™ 440 Cloth Products
• Nextel™ 440 Technical Data

Further information on other 3M™ Nextel™ Ceramic Textiles

• Click for Nextel™ 312
• Click for Nextel™ 550
• Click for Nextel™ 610
• Click for Nextel™ 720

 

Back to Featured Products