Bars 30.5 cm long (12”) in squares of 0.64, 0.95, 1.27, 1.59, 1.91, 2.54, 3.81, 5.08 cm (1/4,
3/8, 1/2, 5/8, 3/4, 1.0, 1.5 & 2.0”).
•
Other sizes, shapes, thicknesses, and configurations are available on special order.
•
In some cases, depending on which Eccosorb MF series is being used, casting of certain
configurations can be done during manufacturing as shown below.
INSTRUCTIONS FOR USE
Termination Design Considerations
:
•
The most widely used member of the Eccosorb MF series is MF-117. It is an excellent
material to start experimentation. Most designs of terminating and attenuating elements
depend heavily upon cut-and-try procedures. A preliminary design is established by
experience or rough estimates of probably satisfactory dimensions, a piece of Eccosorb
MF is machined and tested for VSWR and/or attenuation and the design is then modified
as required.
•
In coaxial, waveguide and strip-line terminations, either step-tapered or uniformly
tapered configurations can be used.
•
Step-tapered terminations are narrow-banded and highly critical dimensionally. They are
recommended only where essentially single frequency operation is anticipated. Increasing
the number of steps beyond two can increase the usable band-width and such designs are
helpful when limited length is available in the direction of propagation. Reproducibility of
the performance of step-tapered terminations may be difficult because of their sensitivity
to small changes in magnetic and dielectric properties.
•
Uniformly tapered terminations are generally preferred because of the low VSWR which is
possible to achieve over a wide frequency range. Dimensions are reasonably non-critical
and performance is reasonably insensitive to magnetic and dielectric properties. In
general, the more gradual the taper, the lower the VSWR. A length-to-base-width ratio of
10:1 is highly desirable for VSWR as low as 1.01 over a full waveguide frequency band,
particularly with materials having the higher values of M' and K'. A sufficiently long taper
must be used so that very little energy reaches the base mounting plate where it can be
reflected back into the line. The one-way attenuation should be at least 25 dB for VSWR
as low as 1.01.
•
Wall-type uniform tapers offer maximum heat-transfer efficiency and are recommended
for high-power applications.
RELATED PRODUCTS
•
For higher temperature applications up to 260 °C, refer to the electrical equivalent
Eccosorb® MF500F.
RFP-DS-MF 092115
A
ny information furnished by Laird Technologies, Inc. and its agents is believed to be accurate and reliable. All specifications are subject to change without notice. Responsibility for the use and application of Laird Technologies materials rests with the
end user. Laird Technologies makes no warranties as to the fitness, merchantability, suitability or non- infringement of any Laird Technologies materials or products for any specific or general uses. Laird Technologies shall not be liable for incidental or
Technologies, Inc. All Rights Reserved. Laird, Laird Technologies, the Laird Technologies Logo, and other marks are trademarks or registered trademarks of Laird Technologies, Inc. or an affiliate company thereof. Other product or service names may be
the property of third parties. Nothing herein provides a license under any Laird Technologies or any third party intellectual property rights.
2
Eccosorb®MF
TYPICAL ELECTRICAL PROPERTIES
E-M PROPERTIES OF ECCOSORB MF
10²
18
0.01
0.18
1.2
0
0
0
0.26
20
0.02
0.40
2.0
0
0
0
0.32
22
0.04
0.88
2.8
0
0
0
0.36
40
0.06
2.4
4.6
0
0
0
0.34
195
0.18
35
5.0
0
0
0
0.16
260
0.40
104
7.0
0
0
0
0.16
320
0.50
160
8.0
0
0
0
0.15
380
0.60
228
9.0
0
0
0
0.14
10
16
0.01
0.16
1.2
0
0
0
0.27
18
0.02
0.36
1.9
0
0
0
0.32
21
0.04
0.84
2.8
0
0
0
0.37
35
0.06
2.1
4.5
0
0
0
0.36
158
0.21
33
5.0
0
0
0
0.18
205
0.39
80
6.9
0
0
0
0.18
250
0.49
123
7.9
0
0
0
0.17
295
0.59
174
8.9
0
0
0
0.16
3
MF-110
MF-112
MF-114
MF-116
MF-117
MF-124
MF-175
MF-190
K’
tan δ
d
K’’
M’
tan δ
m
M’’
dB/cm
|Z|/Z
0
K’
tan δ
d
K’’
M’
tan δ
m
M’’
dB/cm
|Z|/Z
0
K’
tan δ
d
K’’
M’
tan δ
m
M’’
dB/cm
|Z|/Z
0
K’
tan δ
d
K’’
M’
tan δ
m
M’’
dB/cm
|Z|/Z
0
K’
tan δ
d
K’’
M’
tan δ
m
M’’
dB/cm
|Z|/Z
0
K’
tan δ
d
K’’
M’
tan δ
m
M’’
dB/cm
|Z|/Z
0
K’
tan δ
d
K’’
M’
tan δ
m
M’’
dB/cm
|Z|/Z
0
K’
tan δ
d
K’’
M’
tan δ
m
M’’
dB/cm
|Z|/Z
0
10
15
0.02
0.30
1.2
0
0
0
0.28
16
0.03
0.48
1.8
0
0
0
0.34
19
0.04
0.76
2.7
0
0
0
0.38
30
0.07
2.1
4.4
0
0
0
0.38
120
0.23
28
5.0
0
0
0
0.20
145
0.36
52
6.8
0
0
0
0.21
170
0.46
78
7.8
0
0
0
0.20
195
0.56
109
8.8
0
0
0
0.20
4
Frequency Hz
10
5
10
6
13
11
0.02
0.03
0.26
0.33
1.2
1.2
0
0
0
0
0
0
0.30
0.33
14
12
0.03
0.03
0.42
0.36
1.7
1.6
0
0
0
0
0
0
0.35
0.37
18
16
0.05
0.05
0.72
0.80
2.6
2.5
0
0
0
0
0
0
0.38
0.40
26
23
0.07
0.08
1.8
1.8
4.4
4.3
0
0
0
0
0
0
0.41
0.43
85
62
0.24
0.22
20
14
5.0
5.0
0
0
0
0
0
0
0.24
0.28
95
70
0.31
0.26
29
18
6.7
6.6
0
0
0
0
0
0
0.26
0.30
105
78
0.41
0.36
43
28
7.7
7.6
0
0
0
0
0
0.01
0.26
0.30
115
86
0.51
0.46
59
40
8.7
8.6
0
0
0
0
0
0.01
0.26
0.30
10
9.0
0.03
0.27
1.2
0
0
0
0.37
10
0.04
0.40
1.5
0
0
0
0.39
14
0.05
0.70
2.4
0
0
0
0.41
20
0.09
1.8
4.2
0
0
0
0.46
48
0.18
8.6
5.0
0
0
0.03
0.32
52
0.20
10
6.3
0
0
0.03
0.34
56
0.26
15
7.3
0
0
0.05
0.36
60
0.32
19
8.3
0
0
0.06
0.36
7
10
7.0
0.04
0.28
1.1
0
0
0.01
0.40
8
0.04
0.32
1.5
0.01
0.02
0.02
0.43
12
0.05
0.60
2.3
0.04
0.09
0.04
0.44
18
0.08
1.4
4.0
0.04
0.16
0.09
0.47
38
0.12
4.6
4.8
0.1
0.48
0.27
0.36
40
0.14
5.6
6.0
0.2
1.2
0.48
0.39
42
0.16
6.7
7.0
0.4
2.8
0.87
0.42
44
0.18
7.9
8.0
0.6
4.0
1.3
0.46
8
1.0
5.0
0.04
0.20
1.1
0
0
0.09
0.47
6
0.04
0.24
1.4
0.02
0.03
0.16
0.48
11
0.05
0.55
2.1
0.08
0.17
0.57
0.57
17
0.07
1.2
3.0
0.13
0.39
1.3
0.42
28
0.09
2.5
4.1
0.20
0.82
2.8
0.39
32
0.08
2.6
5.0
0.45
2.3
6.5
0.42
36
0.06
2.2
6.0
0.6
3.6
8.6
0.44
40
0.07
2.8
7.0
0.8
5.6
12.6
0.47
3.0
3.2
0.05
0.16
1.1
0
0
0.26
0.59
5.2
0.05
0.26
1.4
0.03
0.04
0.59
0.52
9.9
0.06
0.59
1.9
0.13
0.25
2.2
0.44
16.5
0.06
0.99
2.8
0.21
0.59
5.0
0.42
22.9
0.06
1.4
3.4
0.39
1.33
11.0
0.40
25.8
0.07
1.8
3.8
0.69
2.62
20
0.42
27.0
0.05
1.35
4.4
0.8
3.52
24
0.46
28.0
0.04
1.12
4.5
0.9
4.05
27
0.47
Frequency GHz
8.6
10.0
3.0
2.9
0.05
0.04
0.15
0.12
1.0
1.0
0.10
0.10
0.10
0.10
2.0
2.2
0.59
0.59
5.0
4.8
0.05
0.04
0.25
0.19
1.1
1.1
0.22
0.23
0.24
0.25
4.9
5.6
0.47
0.48
9.8
9.7
0.06
0.05
0.59
0.49
1.3
1.1
0.33
0.40
0.43
0.44
10.8
13.2
0.37
0.35
16.2
16.0
0.07
0.06
1.1
0.96
1.6
1.5
0.47
0.68
0.75
1.02
21
32
0.33
0.33
21.4
21
0.02
0.02
0.42
0.42
1.2
1.1
1.36
1.5
1.63
1.7
46
56
0.30
0.31
23.8
23.6
0.05
0.03
1.19
0.71
2.50
1.5
1.10
1.4
2.75
2.1
63
67
0.39
0.33
25.0
24.0
0.03
0.02
0.75
0.48
1.80
1.3
1.40
1.6
2.5
2.1
65
69
0.35
0.32
26.0
25.0
0.04
0.02
1.04
0.50
2.0
1.5
1.40
1.6
2.8
2.4
70
75
0.36
0.34
18.0
2.8
0.04
0.11
1.0
0.20
0.20
6.6
0.60
4.6
0.03
0.14
1.0
0.26
0.26
10.1
0.47
9.6
0.05
0.48
1.0
0.45
0.45
24.9
0.34
15.8
0.05
0.79
1.4
0.73
1.02
57
0.33
20.6
0.02
0.41
1.0
2.00
2.00
119
0.33
23.0
0.04
0.92
1.0
2.5
2.5
149
0.34
24.0
0.02
0.48
1.1
3.0
3.3
177
0.38
25.0
0.02
0.50
1.1
4.0
4.4
217
0.43
RFP-DS-MF 092115
A
ny information furnished by Laird Technologies, Inc. and its agents is believed to be accurate and reliable. All specifications are subject to change without notice. Responsibility for the use and application of Laird Technologies materials rests with the
end user. Laird Technologies makes no warranties as to the fitness, merchantability, suitability or non- infringement of any Laird Technologies materials or products for any specific or general uses. Laird Technologies shall not be liable for incidental or
Technologies, Inc. All Rights Reserved. Laird, Laird Technologies, the Laird Technologies Logo, and other marks are trademarks or registered trademarks of Laird Technologies, Inc. or an affiliate company thereof. Other product or service names may be
the property of third parties. Nothing herein provides a license under any Laird Technologies or any third party intellectual property rights.
3
Eccosorb®MF
Legend
K'
Real part of the permittivity (dielectric constant)
tan δ
d
Dielectric loss tangent
K
M'
Imaginary part of the permittivity (loss)
Real part of the magnetic permeability
tan δ
m
Magnetic loss tangent
M
Imaginary part of the magnetic permeability (loss)
dB/cm Attenuation per unit distance
dB/in
lZl/Z
0
Attenuation per unit distance
Normalized impedance magnitude ratio
Most of the definitions and equations are included in the Laird publication :
ENERGY PROPAGATION IN DIELECTRIC AND MAGNETIC
MATERIALS.
A copy of this publication can be requested.
In this technical bulletin, μ' is used for the real part of the magnetic permeability and μ for the magnetic loss factor. Beyond the definitions in
the publication above, the clarification of the terms dB/cm (attenuation) and |Z|/Zo (relative impedance) are offered.
These characteristics are not in themselves directly applicable to the calculation of transmission and reflection coefficients as they are defined
on point 3 & 4 of “Energy Propagation in Dielectric and Magnetic Material”. For these calculations, the complex dielectric constant (K'-jK' Tan
δ
d
)
and complex magnetic permeability (M'-jM' Tan
δ
m
) are used as listed in the table.
The definition of dB/unit length is included in the reference, both in mathematical form and in words. The value is useful in comparing one
material against another to determine which offers the most loss independent of interface reflection coefficients. Similarly, |Z|/Zo, the
normalized impedance magnitude ratio, can be used as a qualitative measure of the impedance match between free space and the material. An
impedance ratio that is closest to 1 is the most desirable because at that ratio, the impedance match between the material and free space is
perfect.
The significant features of the property tables are:
1. In every case, K' decreases with increasing frequency.
2 Almost without exception, the dielectric loss tangent and dielectric loss factor decrease with increasing frequency, the exception occurs at the
low end of the frequency band, and can be ignored in most applications.
3.The magnetic loading increases from a minimum in MF-110 to a maximum in MF-190. There is a corresponding increase in K', K , μ', Tan
δ
m
and
μ.
4.The 0 values in the table indicate that the number is less than 0.01.
5.The values given in the table are nominal values and should not be used by customers in the writing of procurement specifications.
If specifications are needed, the customer should consult with the Laird Sales Department.
The use of dielectric/magnetic properties for Quality Control, i.e., incoming or outgoing inspection, is not recommended, because the
measurement of these properties is very time consuming and complicated. It is recommended to monitor the density.
RFP-DS-MF 092115
A
ny information furnished by Laird Technologies, Inc. and its agents is believed to be accurate and reliable. All specifications are subject to change without notice. Responsibility for the use and application of Laird Technologies materials rests with the
end user. Laird Technologies makes no warranties as to the fitness, merchantability, suitability or non- infringement of any Laird Technologies materials or products for any specific or general uses. Laird Technologies shall not be liable for incidental or
Technologies, Inc. All Rights Reserved. Laird, Laird Technologies, the Laird Technologies Logo, and other marks are trademarks or registered trademarks of Laird Technologies, Inc. or an affiliate company thereof. Other product or service names may be
the property of third parties. Nothing herein provides a license under any Laird Technologies or any third party intellectual property rights.
4
Eccosorb®MF
MACHINING RECOMMENDATIONS
Most of the discussion below applies not only to the basic Eccosorb MF series of materials, but also to several high temperatures, castable and
molding-powder equivalents. Eccosorb MF can be formed readily to close tolerances with standard metal-working machine tools, i.e.: lathes,
milling machines, drills, saws, grinders, generally using conventional techniques but observing the precautions and limitations described below.
Tooling :
•
•
•
For turning, milling, drilling and tapping, carbide tools should be used, for example Type 883, a general purpose carbide that works
well under most conditions. Use solid carbide taps for long life. Standard size tap drills should be satisfactory.
External threads are formed best, not with conventional thread-cutting dies but by lathe turning or grinding, with light feeds and
shallow cuts.
Sawing can be done with best finish and tolerance using circular saws, 20.3 to 25.4 cm diameter, with grinding coolant and high RPM.
Thin carborandum wheels, 0,079 cm thick or carbide saws may be used where requirements are less stringent. Best results are
attained by moving the saw and keeping work stationary, with saw rotating so it tends to climb into the work.
Surface finishing of flat sheets, etc. is best performed with a Blanchard grinder. Eccosorb MF is held readily with magnetic chucks.
Sheet size is limited by the size of the machine.
•
Coolants :
•
Use of a coolant liquid is recommended, especially for all close tolerance operations. Commercial grinding fluid is preferred, or water-
soluble oil, with rust-resisting properties to protect the machines. Spark producing operations in particular must not be run dry, since
smoldering fires might result.
Where coolant run-off is collected for recirculation, a two-cavity recovery system should be used to minimize pick-up of grinding dust,
sawdust or chips by the coolant pump. Where a re-circulating system is not available, best results will be obtained with air-powered
spray or mist equipment.
•
Use of tapped metal inserts should be considered where electrical performance will not be degraded. Inserts may be cast in place, or bonded
with castable material of suitable composition.
Suggested Speeds and Feed Rates
The following speeds and feed rates are suggested to be modified as necessary to suit job conditions:
OPERATION
Sawing, turning
SPEED
21.3 - 27.4 m/min
(70-90 ft/min)
21.3 - 27.4 m/min
70-90 ft/minute
450 rpm
21.3 - 27.4 m/min.
70-90 ft/min
FEED
0.13 - 0.20 mm
.005-.008 in/revolution
0.038 mm/pass
.001 in/pass
Tapping Head
0.038 - 0.076 mm/tooth
.0015-.003 in/tooth
External threading
Tapping
Milling
RFP-DS-MF 092115
A
ny information furnished by Laird Technologies, Inc. and its agents is believed to be accurate and reliable. All specifications are subject to change without notice. Responsibility for the use and application of Laird Technologies materials rests with the
end user. Laird Technologies makes no warranties as to the fitness, merchantability, suitability or non- infringement of any Laird Technologies materials or products for any specific or general uses. Laird Technologies shall not be liable for incidental or
Technologies, Inc. All Rights Reserved. Laird, Laird Technologies, the Laird Technologies Logo, and other marks are trademarks or registered trademarks of Laird Technologies, Inc. or an affiliate company thereof. Other product or service names may be
the property of third parties. Nothing herein provides a license under any Laird Technologies or any third party intellectual property rights.