Compression resin transfer infusion methods

A method of compression resin transfer infusion comprising:

• injecting resin into a gap of a sealed cavity of an infusion and cure tool while the infusion and cure tool is maintained at an infusion temperature;
• lowering an upper mold die of the infusion and cure tool to infuse a dry preform in the sealed cavity with the resin in a resin latency condition to form a resin-infused preform;
• increasing the infusion and cure tool's temperature from the infusion temperature to a curing temperature at a desired ramp rate;
• curing the resin-infused preform in the infusion and cure tool to form a cured composite part, wherein curing occurs at the curing temperature higher than the infusion temperature, wherein the curing temperature is sufficient to cause a thermoplastic veil in the dry preform to expand and melt, joining the resin to the thermoplastic veil;
• and
• lowering a temperature of the infusion and cure tool after the curing from the curing temperature at a ramp down rate, wherein the curing temperature and the ramp down rate are selected to generate cavitation bubbles in the thermoplastic veil in the cured composite part.

A method of compression resin transfer infusion to form cavitation bubbles in a cured composite part comprising:

• injecting resin into a gap of a sealed cavity of an infusion and cure tool while the infusion and cure tool is maintained at an infusion temperature;
• lowering an upper mold die of the infusion and cure tool to infuse a dry preform in the sealed cavity through its thickness with the resin to form a resin-infused preform, the dry preform comprising a thermoplastic veil;
• increasing the infusion and cure tool's temperature from the infusion temperature to expand the thermoplastic veil while it melts;
• curing the resin-infused preform in the infusion and cure tool to form a cured composite part;
• and
• lowering the temperature of the infusion and cure tool after curing to contract the thermoplastic veil in the cured composite part as the thermoplastic veil cools below a melting temperature of the thermoplastic veil to generate cavitation bubbles in the thermoplastic veil.