Inductance coil is widely used in the electrical industry. It is the most important feature of inductance coil that "resists high frequency and connects low frequency". When high-frequency signal passes through the inductance coil, it will encounter great resistance and be difficult to pass through. However, when low-frequency signal passes through it, it will show little resistance. The resistance of inductance coil to DC is almost zero, which has an obvious blocking effect on AC current.

Generally speaking, the wire winding the inductance coil has a certain resistance, which is usually very small and can be ignored. However, when the current flowing through some circuits is large, the small resistance of the coil can not be ignored, because the large current will consume power on the coil, causing the coil to heat up or even burn out. Therefore, sometimes the electrical power that the coil can withstand should be considered.

It can be seen that the plastic coil framework is one of the key parts of electrical protection products.

The materials used for the coil framework must meet the following requirements:

Can withstand the maximum coil temperature

Good insulation performance

Convenient for processing and forming

Characteristics of special modified PBT for coil framework:

1. High grade flame retardant

In the selection of materials for general electronic products, special attention is paid to its fire protection performance. Selecting high-grade fire-proof materials is of great significance to improve the product safety level and prevent fire.

Especially for the coil framework materials, when the coil current winding the framework is too large, it will often cause the coil to heat up or even burn out. The materials whose flame retardant level does not meet the requirements will inevitably have certain potential safety hazards

The specially modified PBT for the coil framework can reach the level of 0.38mmv0, ensuring the safety of the coil framework for safe use.

2. High CTI

Relative leakage trace index: the highest voltage value that the material surface can withstand 50 drops of electrolyte (0.1% ammonium chloride aqueous solution) without forming leakage traces. Polymer insulating materials have a special phenomenon of electrical damage, that is, the surface of polymer insulating materials will suffer from electric trace deterioration under specific conditions, and can lead to electric trace damage.

For the products used in some electronic components such as coil framework, they have high requirements for CTI value. The specially modified PBT for coil frame not only has excellent flame retardancy, but also has excellent leakage trace index, which can reach 250V, and has excellent safety performance.

3. High mechanical performance

General electronic products do not pay special attention to mechanical properties in the selection of materials, but for some special products, if the mechanical properties are insufficient, the products will be broken or brittle. Therefore, it is of great significance for customers to avoid using bad products and improve the mechanical properties of products.

4. High liquidity

For a material, good fluidity means easy processing and molding, lower processing temperature, lower injection pressure and lower energy consumption. Especially for the "one mold, multiple holes" products such as relays, capacitor shells and coil frames, choosing a material with good fluidity is more beneficial to injection molding, so as to avoid dissatisfaction or defects due to insufficient fluidity. The specially modified PBT for coil framework has good fluidity and excellent processing performance.

This article is from PBT engineering plastics:http://www.wywantong.com/