Bubbles/voids inside the board

Bubble-shaped voids exist in the cross-section or interior of the laminate. This defect is usually discovered after demolding or during cross-section inspection, mostly concentrated in thick-wall areas or at the end of resin flow. Internal defects reduce the mechanical strength and compactness of the product, and have a particularly serious impact on products with pressure-bearing and sealing requirements.

(1) Gas removal aspect: interlayer air not completely removed; gas retention forms internal defects affecting product compactness. (2) Gas removal aspect: dissolved gas or volatiles in the resin escaping; gas retention forms internal defects affecting product compactness. (3) Material aspect: volatile content or moisture in raw materials exceeding standard, vaporizing at molding temperature to form bubble sources. (4) Process aspect: air entrainment during filling or pouring, with insufficient venting/degassing measures. (5) Mold aspect: unreasonable cavity venting structure design, gas cannot be effectively discharged.

(1) Process enhancement: use vacuum-assisted layup and hot pressing process; increase vacuum degree and ensure sufficient processing time, and proceed to the next process after confirming that bubbles are completely eliminated. (2) Implementation measures: fully roll-press each layer during layup to vent gas; formulate specific operation plans based on actual production conditions and verify implementation effects. (3) Material selection: use degassed resin., establish material selection evaluation standards and determine the optimal solution through comparative tests. (4) Preventive measures: establish standardized degassing and casting operating procedures, regularly train operators, and check the first piece of each shift to confirm there are no bubble defects.

The essence of this problem is that gas was not effectively removed during the lamination '2079851475616104453, requiring coordinated solutions from three aspects: degassing process, casting method, and venting design.