Patent ID: 6928731

Claim:
An ink jet print head manufacturing process in which multiple metallic surfaces having aligned openings are ultrasonically bonded to form an internal ink cavity, comprising: establishing bonding material interfaces between different pairs of adjacent metallic surfaces to form an assembled metallic stack, the metallic surfaces having openings and the assembled stack having first and second major surfaces; the establishing of bonding material interfaces including introducing a layer of bonding material between each pair of the adjacent metallic surfaces and positioning the adjacent metallic surfaces of each pair in a confronting relationship with their openings aligned to form an ink cavity in the metallic stack, the bonding material at each bonding material interface having a melting temperature and comprising a metallic formulation including tin or a tin alloy; positioning first and second beryllium copper spacers in contact with the respective first and second major surfaces to form a spacer-bounded assembled metallic stack; heating the spacer-bounded assembled metallic stack to a temperature that softens but is below the melting temperature of the bonding material at each bonding material interface; and applying an ultrasonic force to the spacer-bounded assembled metallic stack at a bonding pressure and at an ultrasonic vibration frequency for a time sufficient for the bonding material at each bonding material interface to wet and thereby promote completion of bonding of the metallic surfaces and prevent bonding material blockage of the aligned openings.