CALORIMETRIC SYSTEM FOR MEASUREMENT OF NET POWER IN LASER AND ARC WELDING AND CLADDING

摘要

The Power Measurement Calorimetric System (PMCS)was developed as a part of a program funded by theOffice of Naval Research (ONR) in cooperation withPuget Sound Naval Shipyard - IntermediateMaintenance Facility (PSNS-IMF). The primaryobjective of the PMCS is to measure the High PowerDirect Diode (HPDD) laser beam net power transferredto a substrate (up to 4,000 W). With this informationwe can ensure reliable and repeatable control of theheat input in a cladding process. The PMCS isdesigned for users who perform welding/cladding oncomponents that require accurate and repeatablecontrol of heat input, such as critical components madeof heat-sensitive steels. In comparison with the popularSeebeck Envelope Calorimeter (SEC), the PMCS is acomplete turnkey device that generates data on netpower, in watts rather than as a voltage output signal.It takes measurements with production-oriented speedof 3 minutes per measurement (instead of 6 hours).The PMCS can be used for research to determinethermal efficiency of different laser beams (includingHPDD, YAG and CO2), using different substrates andfiller metals. It can also be used for gas tungsten arcwelding. The PMCS measures the net power atconditions very close to those encountered in realwelding/cladding using the same base and fillermaterials, and programming parameters. The PMCS isbuilt as a stand-alone unit and has a built in calibratingsystem that ensures and maintains high accuracy ofpower measurements. This paper is a report of interimresults of testing the PMCS.