Translate The Website (Starts on Home Page)

PayPal, Visa, MasterCard, American Express, Discover Cards Accepted
Freedom Isn't Free R A Mayes Logo and Home Page Call Nationwide 1-800-742-9447
Flat Foam Radar Absorber
    

PPG Cuming Microwave Logo

Cuming Microwave Corporation is at the forefront of innovative microwave absorber technology and materials for the RF Electromagnetic Interference, Radar Cross Section Reduction and Anechoic Chamber markets. From dielectric, artificial dielectrics, radomes, RF absorbers, and anechoic chambers for the international aerospace, electronics, and defense industries. From thin resonant absorption sheets to 12 foot pyramids to radar reflectors for mach speed aircraft; from do-it-yourself anechoic test chambers to turnkey anechoic chambers.

Cuming Microwave is a ISO 9001 Certified Manufacturer

ROHS 

 

Flexible Flat Foam Microwave Absorber

 

C-RAM LF

 

Available in 2 Weatherproof Versions

 

FLEXIBLE FOAM SHEET

BROADBAND MICROWAVE ABSORBER

Multi-Layer Graded Carbon

 

Flexible Foam

600 MHz - 40 GHz

 

 

 

Data 

 

PSA

 

C-RAM LF is a series of lightweight, flexible, broadband radar absorbers made from graded layers of lossy open-cell plastic foam. It is designed to provide typically 20 dB of reflectivity reduction in a frequency range dependent upon grade. The product is flexible enough to conform to moderately contoured surfaces. CRAM LF is useful for reducing reflections in radar test ranges, inside radomes, around antennas, and for modifying antenna radiation patterns.

 

It is also available in two weatherproof versions:

C-RAM LF-W is standard LF absorber wrapped in a thin weatherproof fabric tarp. The coating on this tarp is polychloroprene. Color is olive green. For severe weathering conditions, the product can be supplied wrapped in a white colored hypalon tarp which will withstand long term sun and rain exposure, but with a penalty of reduced reflectivity performance.

C-RAM LF-HCN is standard LF absorber wrapped in a thin weatherproof white Hypalon fabric tarp.

Data

Standard product size for all grades of LF are a flat panel 610 x 610 mm (24 x 24 in.).

Other dimensions are possible, including larger parts formed by butt-joining sections together.

 

INSERTION LOSS AND ATTENUATION (C-RAM LF)

Model

Thickness

Weight

Performance

Frequency

 

mm

in

kg

lb

Reflectivity

Range of use

LF-72

6.4

0.25”

0.25

0.55

-20 dB

above 18 GHz

LF-73

9.5

0.38”

0.40

0.90

-20 dB

above 7.5 GHz

LF-74

19.1

0.75”

0.70

1.55

-20 dB

above 3.5 GHz

LF-75

28.6

1.13”

0.80

1.75

-20 dB

above 2.5 GHz

LF-77

57.2

2.25”

1.50

3.30

-20 dB

above 1.3 GHz

LF-79

114.3

4.50”

2.95

6.50

-20 dB

above 0.6 GHz

 

Reticulated Foam Microwave Absorber

 

C-RAM AR

 

SP - Standard Performance

HP - High Performance

 

BROADBAND

RETICULATED FOAM
RADAR ABSORBER

2 GHz - 100 GHz

 

 

 

Data 

 

PSA

 

C-RAM AR is a line of reticulated foam Radar Absorbing sheet materials, comprised of urethane foam and a gradient lossy coating C-RAM AR absorbs microwave energy across a wide range of frequencies. Typically the thicker the material the lower in frequency C-RAM AR will attenuate.

C-RAM AR has proven to be ideal for lining shrouds of communications antennas for the suppression of side lobes. It can also be used to cover fences to separate adjacent antennas, and shield or isolate equipment. The open-cell structure permits airflow freely through the absorber, also when used outdoors rain will freely drain from the product.

Cuming Microwave Corporation offers two types of C-RAM AR, our standard performance AR and high performance AR.

C-RAM AR is available in standard sizes of 24 x 24 in (610 X 610mm) and 24 x48 in. (610 x 1200mm).

Other sizes are available. Cuming Microwave can also supply parts cut to drawings. Consult the factory for alternative sizes.

 

 

Standard Performance (SP) Grade:

Thickness

Performance

Freq. Range

0.375 in.

-12 dB

10 GHz & Up

0.50 in

-12 dB

8 GHz & Up

0.75 in.

-12 dB

6 GHz & Up

1.0 in.

-12 dB

6 GHz & Up

1.25 in.

-12 dB

5 GHz & Up

2.0 in.

-12 dB

3 GHz & Up

Standard Performance (HP) Grade:

Thickness

Performance

Freq. Range

0.375 in.

-20 dB

10 GHz & Up

0.50 in

-20 dB

8 GHz & Up

0.75 in.

-20 dB

6 GHz & Up

1.0 in.

-20 dB

6 GHz & Up

1.25 in.

-20 dB

5 GHz & Up

2.0 in.

-20 dB

3 GHz & Up

 

Lossy, Carbon Filled, Flexible Flat Foam Microwave Absorber

 

C-RAM MT

 

1/4" to 4.0" High x

24" x 24" (610 x 610 mm)

 

CARBON FILLED

FLEXIBLE FOAM SHEET

1 GHz - 100 GHz

 

 

 

Data 

 

PSA

 

C-RAM MT is a series of flexible, lightweight lossy plastic foam sheet materials. A very broad frequency range of dielectric loss is achieved through carbon loading of the foam. C-RAM MT can be used to lower the Q of cavities, attenuate surface currents, absorb stray RF energy, isolate components, and plug areas of RF leakage.


It is a lossy load material; applications requiring a free space reduction of reflectivity should be addressed with C-RAM LF.

C-RAM MT is available in several grades having varying levels of carbon loading, hence varying loss tangents. Each grade is available in a range of thickness’. The material is a soft foam and is easily cut with a sharp knife.

Cuming Corporation can also supply C-RAM MT with a peel-and-stick backing, and can die-cut or machine parts to specifications.

 

 

INSERTION LOSS AND ATTENUATION (C-RAM MT)

MODEL

INSERTION LOSS. dB/cm (dB/inch)

ATTENUATION, dB/cm (dB/inch)

 

1 GHz

3 GHz

10 GHz

3GHz

MT-14

0.2 (0.5)

0.4 (1.0)

0.9 (2.2)

0.4 (1.0)

MT-16

0.7 (1.8)

1.5 (3.8)

2.0 (5.0)

1.4 (3.5)

MT-18

0.9 (2.3)

1.8 (4.0)

2.8 (7.0)

1.5 (3.7)

MT-20

1.8 (4.5)

3.2 (8.0)

5.1 (13.0)

3.0 (7.5)

MT-22

2.2 (5.5)

3.9 (10.0)

6.3 (16)

3.7 (9.5)

MT-24

3.5 (14)

11 (32)

24 (60)

11 (27)

MT-26

4.9 (19)

16 (46)

34 (89)

16 (39)

MT-30

16 (40)

24 (60)

43 (110)

19 (49)

NOTE: Insertion loss measurements include the effects of surface reflections; the above values are close to, but not exactly, linear with thickness. For example, a 1/4 inch thick piece has somewhat more than 1/4th as much insertion loss as a one inch thick piece. Attenuation is a measure of loss within a homogeneous material, and does not take into account any reflections at interfaces. It is independent of thickness. This is calculated, not a measured value.

 

Silicone Rubber Microwave Absorber Sheet Material

 

C-RAM RGD-S

 

Standard product sizes for both grades are flat
sheets 12 x 12 in (305 x 305 mm), available in
several standard thicknesses including:
0.030 in (0.76 mm)
0.040 in (1.02 mm)
0.060 in (1.52 mm)
0.125 in (3.17 mm)
0.250 in (6.35 mm)

1.5 GHz - 10 GHz

 

Cuming RDG-S Absorber 

 

 

Data 

 

PSA

 

C-RAM RGD-S is a filled silicone rubber microwave absorber sheet material with a high magnetic loss. It is available in three grades: -117, -124 and -192. The -192 grade has higher loading and higher losses.C-RAM RGD-S is used for terminations, loads, and attenuators in waveguides, coaxial lines, and microstrip circuits.

It can also be used for lowering the Q of cavities and eliminating unwanted resonances.C-RAM RGD-S is cut readily with a sharp knife, and can be sawed, die cut, waterjet cut, or otherwise machined to complex shapes. Since it is ferromagnetic, it is easily held in place during machining with magnetic chucks.

It is flexible and can be bonded to contoured surfaces.Because it is flexible, C-RAM RGD-S can withstand temperature cycling when bonded to metals.

The material has good thermal conductivity and can be used to dissipate heat, including that generated by its own magnetic loss mechanism. 

TYPICAL PROPERTIES
Color: Grey
Flammability: non-flammable
Specific Gravity: 4.0
Thermal Expansion per ºC: 6 x 10-5
Thermal Conductivity: .0021 cal-cm/sec-cm2-ºC
6.0 BTU-in/hr-ft2-oF
Service Temperature: -55 to +200° C
(-65 to +400°F)
Hardness, Shore A: 75
Water Absorption, 24 hrs: <0.1%
Volume Resistivity, ohm-cm: >1010
Dielectric Strength, kV/mm: >400 (>100 V/mil)
Relative Impedance (Z/Zo):

0.3 for -117
0.4 for -124
0.6 for -192

 

ATTENUATION dB/cm

Frequency

LOSS. dB/cm

 

-117 (Z/Zₒ 0.3)

-124 (Z/Zₒ 0.4)

-192 (Z/Zₒ 0.6)

1.5 GHz

2.9

5.6

7

3.0 GHz

11

20

24

8.6 GHz

46

63

70

10 GHz

51

69

80

Note: attenuation is a measure of the absorption of RF energy within the material, and is not the same as insertion loss, which includes reflected energy at the air-material interface

 


Last Updated: April 26, 2018
Copyright © 2001-2018  R. A. Mayes Company, Inc.
An Electro Mechanical Research and Development (EMRAD) Corporation, Company
Privacy Policy
 

All the Data Sheets on our website require Adobe Acrobat Reader! Get Abode Reader