Process for welding and soldering by means of a beam of charged particles

Claim 1

A PROCESS FOR JOINING AT LEAST A FIRST PAIR OF WORK PIECES WHICH COMPRISES THE STEPS OF: GENERATING AN INTESNSE BEAM OF ELECTRONS; POSITIONING THE PIECES TO BE JOINED IN ABUTTING RELATIONSHIP IN LINE WITH THE BEAM; INCREASING THE BEAM POWER DENSITY IN ACCORDANCE WITH A PREDETERMINED SCHEDULE OVER A FIRST PERIOD OF TIME TO A THRESHOLD LEVEL SUFFICIENT TO PROMOTE EVAPORATION OF AND TO THUS PERMIT PENETRATION OF THE BEAM INTO THE WORK; MAINTAINING THE BEAM POWER DENSITY ABOVE THE THRESHOLD LEVEL FOR A SECOND PERIOD OF TIME LESS IN DURATION THAN SAID FIRST PERIOD OF TIME WHEREBY MELTING AND FUSION OF THE WORK OVER THE ENTIRE DEPTH OF THE PENETRATING BEAM WILL RESULT DURING SAID MAINTENANCE PERIOD; AND DECREASING THE BEAM POWER DENSITY IN ACCORDANCE WITH A PREDETERMINED SCHEDULE, THE TIME REQUIRED TO DECREASE THE POWER DENSITY FROM THE THRESHOLD TO ITS FINAL LEVEL BEING AT LEAST EQUAL TO SAID FIRST PERIOD OF TIME, WHEREBY CONTROLLED COOLING OF THE FUSION ZONE OCCURS AND A RESOLIDIFIED ZONE FREE OF CAVITIES RESULTS.