Resistor cores

We supply ceramic cores for resistors and other electrical components. It is also possible to manufacture ceramic cores to your
own drawings.

Please find a list of our standard cores below (status October 01 2011):
Ser. No. Product No. External dimensions of product Fig.
Length L mm Diameter D mm Radius R mm
1 CR13 1.3±0.02 2.7±0.08 0,25~0,35
2 CR17 1.7±0.03 5.2±0.1 0,35~0,45
3 CR232 2.32+0.015 6.2-0.3 0,35~0,55
4 CR3 3±0.03 8±0.15 0,40~0,70
5 CR35 3.5±0.04 10±0.20 0,40~0,70
6 CR4 4±0.05 14±0.3 0,50~0,80
7 CR54 5.4+0.06 11.8-0.5 0,50~0,81
8 CR74 7.4+0.065 17-0.6 0,60~1,00

We can supply a choice of two types of material with Al2O3 contents of at least 68% and 95% respectively. The properties of the materials are specified in the following list:

Parameters of material with an Al2O3 content of at least 68%:

Ser. No. Designation of property Value of property

1

Minimum density, g/cm3

3.1

2

Maximum water absorption in %

0.01

3

Minimum bending strength sи МPа

170

4

Mean linear coefficient of thermal expansion at temperatures of 20°C to 800°С

6.7x10-6

5

Thermal conductivity W·m-1·К-1 at temperatures of 20°C to 100°С

4,1

6

Minimum dielectric strength kV·mm-1 at frequency of 50 Hz

10

7

Minimum specific volume resistivity at a temperature of 20°С

1014

8

Relative permittivity at frequency of 1 МHz

7.5

9

Maximum dielectric loss factor at frequency of 1MHz

>0.01

10

Surface finish of manufactured products Ra

0.5

 

Properties of material with 95% Al2O3 content:

Ser. No.

Designation of property

Value of property

1

Minimum density, g/cm3

3.6

2

Maximum water absorption in %

0.01

3

Minimum bending strength sи МPа

300

4

Mean linear coefficient of thermal expansion at temperatures of 20°C to 800°С

8x10-6

5

Thermal conductivity W·m-1·К-1 at temperatures of 20°C to 100°С

25

6

Minimum dielectric strength kV·mm-1 at frequency of 50 Hz

15

7

Minimum specific volume resistivity at a temperature of 20°С

>1012

8

Relative permittivity at frequency of 1 МHz

9.,5

9

Maximum dielectric loss factor at frequency of 50 Hz

0.5

10

Surface finish of manufactured products Ra

0.4