Decreased electrical insulation strength of laminated products

The breakdown voltage of insulating laminates is lower than the design value. The decline in mechanical properties is usually only discovered during product service or testing stages, and is concealed. This defect significantly reduces the mechanical properties and service life of the product and may cause early failure of the product during service.

(1) Raw material characteristics aspect: tiny pores or impurity particles inside the product forming weak-point breakdown channels; the physical characteristics of the powder directly affect preforming and sintering quality. (2) Gas removal aspect: insufficient resin content forming continuous air gaps between fibers; gas retention forms internal defects affecting product compactness. (3) Material aspect: low molecular weight or degradation causing decreased molecular chain strength. (4) Process aspect: insufficient sintering or curing, inadequate inter-particle bonding. (5) Formulation aspect: crosslink density or filler ratio deviating from the optimal value.

(1) Process enhancement: vacuum-assisted lamination to eliminate air gaps; increase vacuum degree and ensure sufficient processing time, and proceed to the next process after confirming that bubbles are completely eliminated. (2) Implementation measures: increase resin content for full impregnation; formulate specific operation plans based on actual production conditions and verify implementation effects. (3) Process control: control raw material purity., establish an online monitoring mechanism, set parameter upper and lower limits and implement alarm management. (4) Preventive measures: establish a raw material batch inspection system, regularly sample product density and mechanical properties, and establish quality trend analysis.

The core cause of insufficient mechanical properties is inadequate material bonding or degradation; the sintering/curing process needs to be optimized and raw material quality controlled.