The circuit board must be fire resistant. It cannot be burned at a certain temperature of BAI, but can only be soft du.At this point, the temperature point is called zhi glass state transformation DAO temperature (Tg point), which is related to the dimensional stability of PCB board.

Tg refers to the glass transition temperature of the sheet.Normal Tg is about 130~150C, and high Tg can reach 170-210C

FR4 copper clad laminate is short for glass fiber epoxy resin coated laminate.

FR4 copper clad laminate is divided into the following grades:

First: FR-4 A1 class copper clad laminate

This grade is mainly used in military industry, communication, computer, digital circuit, industrial instrument and meter, automobile circuit and other electronic products.The quality of this series of products has reached the world first-class level, the highest grade and the best performance.

Second: FR-4 Grade A2 copper clad laminate

This class is mainly used for ordinary computers, instruments, high - grade home appliances and general electronic products.This series of copper clad laminates are widely used, and each performance index can meet the needs of general industrial electronic products.Has a good price performance ratio.Customers can effectively improve the price competitiveness.

Third: FR-4 A3 copper clad laminate

This grade copper clad laminate is the FR-4 product specially developed for the home appliance industry, computer peripheral products and general electronic products (such as toys, calculators, game consoles, etc.).Its characteristic lies in the performance meets the requirement under the premise, the price has the competitive advantage extremely.

Fourth: FR-4 A4 class copper clad laminate

This grade plate belongs to FR-4 copper clad plate low end material.But each performance index still can satisfy the need of common home appliance, computer and general electron product, its price has competition most, performance compares price quite also excellent.

Fifth: FR-4 Class B copper clad laminate

The boards of this grade are relatively poor with poor quality stability, so they are not suitable for large-area circuit board products. Generally, they are suitable for products with a size of 100mmX200mm.