The quality control of prepreg production is generally divided into three stages: raw material quality control, process quality control (process control), and finished product quality control.
Raw material quality control
The main raw materials must be inspected in the factory and can be put into storage only after they are qualified. If there is no standard, standards must be established and implemented according to the standards. The main raw materials should be supplied on a fixed-point basis instead of raw materials from non-designated suppliers. The performance evaluation of designated suppliers is required to ensure the stability of raw material quality. For new suppliers, they must go through the performance test and inspection of the samples to determine whether they are qualified or not, so as to initially determine whether their products can be accepted in terms of quality, and evaluate after production trials before they can be listed as designated suppliers .
Process quality control
Quality control of the compounding process
Must use materials that have passed the inspection of the Quality Department or are allowed to be used
The solid material must be crushed to meet the requirements
Strictly control the moisture absorption of materials
Proportioning: the proportion of each component material is accurately weighed, and the mixing and feeding sequence is correct
Temperature: precise control, no over temperature, to prevent explosion
Time: try to shorten the time under a certain temperature and extend the storage period
Humidity below 65%
Cleanliness: strictly prevent foreign mechanical impurities from entering the resin
In the control
The particle size and distribution of solid powder have been inspected by central control
The gel time (125C) and viscosity (70C) of the resin matrix have been tested by central control.