1. Definition and composition
– Insulated Bakelite board is a kind of board with good insulating properties. It is mainly made of phenolic resin as the base material, adding a certain proportion of wood powder and other fillers, and made by hot pressing and other processes. Phenolic resin itself has high insulation and mechanical strength, and the addition of wood powder can improve some physical properties of the material, such as toughness.
2. Physical Properties
– Color and Appearance**: it is usually brown or black with a relatively flat surface. It has a certain gloss, which is due to the smooth surface formed by the resin during the molding process.
– Density: Its density is usually between 1.3 – 1.45g/cm³, which is moderate, neither too heavy nor too light, convenient to be used in all kinds of electrical equipments, which will not increase the burden of the equipments because of being too heavy, and will not affect its stability because of being too light.
– Hardness: Higher hardness, roughly 2 – 2.5 on the Mohs scale. This makes it able to withstand a certain degree of external force, and it is not easily scratched or damaged during installation and use, so that it can well protect the internal electrical components.
– MECHANICAL STRENGTH: It has good mechanical strength, including compressive strength and bending strength. The compressive strength can generally reach 70 – 100 MPa, and the bending strength is about 30 – 50 MPa. This strength ensures that it can work properly in some electrical equipment that needs to withstand pressure or bending force, such as as the insulating partition of the motor.
3. Insulation properties
– Insulation Resistance: Insulating Bakelite board has a very high insulation resistance, which can reach about 10¹⁰ – 10¹²Ω-m under normal conditions. This means that it can effectively stop the leakage of current and ensure the safety of electrical equipment. Even in humid environments, its insulation resistance can be maintained at a high level, reducing the probability of leakage accidents.
– Dielectric constant: The dielectric constant is generally between 4 – 5 (at 1kHz frequency). The dielectric constant is a physical quantity that measures the ability of a dielectric to store electrical energy in an electric field. This value indicates that it has better energy storage characteristics in an electric field and is suitable for use as an insulating material for electrical components such as capacitors.
– **Breakdown Voltage**: Its breakdown voltage is high, generally can reach 10 – 20kV/mm. when the electric field strength exceeds the breakdown voltage, the insulating material will lose the insulating property and conduct electricity, higher breakdown voltage makes the insulating bakelite boards can withstand higher voltage without being broken down, thus ensuring the safe operation of the electrical equipment under the rated voltage.
4. Thermal properties
– Operating temperature range: insulated bakelite boards can work normally in a certain temperature range, the general operating temperature range is -40℃ – 120℃. In this temperature range, its physical and insulating properties are basically stable. When the temperature exceeds this range, its performance may gradually decline, for example, at high temperatures, the resin may soften, affecting its mechanical strength and insulating properties.
– Thermal conductivity: The thermal conductivity is low, around 0.2 – 0.3W/(m-K). This makes it a good insulator, which prevents rapid heat transfer in some electrical equipment and avoids damage to electrical components due to localized overheating.
5. Processing performance
– Insulated Bakelite board is easy to cut, drill and other mechanical processing. It can be processed using common woodworking tools or machining equipment. For example, it can be easily cut to the desired shape and size using a chainsaw, and mounting holes can be drilled in it using a drill press, etc. It can also be surface treated by grinding etc. to meet different installation and usage requirements.
6. **Application fields**
– Electrical equipment: It is used as an insulating partition in motors, transformers and other equipment to prevent current from leaking between different conductive parts and to ensure the normal operation of the equipment and the safety of the operators.
– Electrical and electronic products: such as in the manufacturing process of circuit boards, as an insulating substrate, to provide a mounting base for electronic components and insulation protection to prevent short circuits between components.
– Electrical tools: The handle part of some electrical tools will also be made with insulated bakelite boards, which can prevent electric shock accidents during operation.
