High strain rate compressive deformation behavior of an additively manufactured stainless steel

In this work the effect of manufacturing strategy and post process treatment on the high strain rate (HSR) compressive deformation behavior of additively manufactured powder bed fusion 17-4PH stainless steel is studied. Specimens were fabricated using three different laser vector path strategies to impart different thermal histories and resulting microstructures in the material. The effect of post processing in the form of hot isostatic pressing and heat treatment and their effect on HSR compressive deformation response of the material was studied. Defect characteristics were quantified using x-ray micro computed tomography. HSR behavior was characterized using split Hokinson bar testing at rates from 1000-4000 s(-1). It was found that the laser vector strategy had a strong influence on the development of microstructure and defect characteristics and spatial distribution in the materials which strongly influence the HSR response and the HSR compressive flow stresses of the materials varied by as much as 43% in the regimes tested.