THE EFFECT OF PROCESS PARAMETERS ON RESIDUAL STRESSES WITHIN ANINCONEL 718 PART PRODUCED BY THE DIRECT LASER DEPOSITION PROCESS

摘要

The residual stress fields generated within a laserdeposition metal component or added feature have thepotential to significantly affect its properties andperformance. Stresses play a major role in determiningthe initial levels of distortion, in both the added partand the initial substrate material, and affect both short-timeproperties, such as ductility, and long-timeproperties, such as creep and corrosion resistance.Their control is therefore essential for the productionquality demanded in high performance aerospacecomponents. In this work, a series of geometricallysimple components was additively manufactured fromInconel 718 powder using a coaxial diode laserdeposition system under a range of process parameters.The residual surface stresses arising were measuredusing x-ray diffraction techniques and the variations inthem with surface position and process parameters areshown. The formation of these stresses and theirrelationship to Direct Laser Deposition processparameters are discussed.