US Patent 10081129 Additive manufacturing system implementing hardener pre-impregnation

A method is disclosed for additively manufacturing a composite structure. The method may include directing a continuous reinforcement into a print head, and coating the continuous reinforcement with a first matrix component inside of the print head. The method may further include coating the continuous reinforcement with a second matrix component, discharging the continuous reinforcement through a nozzle of the print head, and moving the print head in multiple dimensions during the discharging. The first and second matrix components interact to cause hardening of a matrix around the continuous reinforcement.