The criterion of flame retardant grade of thermal conductive silica gel sheet and the difference of test are introduced

We often say that the fire rating of thermal conductive silica gel is actually the flame retardant grade of thermal conductive silica gel, and the flame retardant grade of thermal conductive silica gel is a relatively important parameter in the many performance parameters of thermal conductive silica gel. Through the test report of thermal conductive silica gel sheet, we can know that all the flame retardant grade of thermal conductive silica gel sheet produced by us is UL-94 V0. In front of the introduction of "What is the thermal conductivity? Thermal conductivity of thermal materials and test methods", today to introduce the thermal silicone sheet flame retardant rating criteria and test differences.

The standard and difference of flame retardant grade HB involved in thermal conductive silicone sheet:

Standard: UL94 Judgment grade: HB

Specific requirements for decision level:

1, the combustion distance is 75mm, the sample thickness is 3.0-13mm, the combustion speed is less than 40mm/min,

2, the combustion distance is 75mm, the sample thickness is < 3.0mm, the combustion speed is less than 75mm/min,

3, the flame stops before the 100mm marking line;

4, the combustion distance is 75mm, the sample thickness is 3.0mm+0.2mm, the combustion speed is less than 40mm/min, then when the minimum thickness is 1.5mm, it should be automatically accepted as the level.

Standard: GB/T 2408 IEC60695-11-10 Grade: HB, HB40, HB75

Heat-conducting silicone sheet flame retardant HB rating:

1. There should be no obvious flame burning after removing the ignition source;

2. If the test sample continues to burn after removing the ignition source, the flame front should not pass the 100mm mark line;

3. Combustion distance 75mm, sample thickness 3.0-13mm, combustion speed ≤40mm/min; The combustion distance is 75mm, the sample thickness is less than 3.0mm, and the combustion speed is less than 75mm/min

4. Combustion distance 75mm, sample thickness 3.0mm±0.2mm, combustion speed ≤40mm/min; Then when the minimum thickness is reduced to 1.5mm, it should be automatically accepted as that level.

Materials classified as HB40 shall meet one of the following criteria:

1. There should be no obvious flame burning after removing the ignition source;

2, if the test sample continues to burn after removing the ignition source, the flame front should not pass the 100mm mark line;

3, if the flame front passes the 100mm mark line, the linear burning rate should not be greater than 40mm/min.

Class HB75: Even if the flame front passes the 100mm mark line, the linear burning rate of the material should not be greater than 75mm/min