Two primary variables that impact failure behavior of ductile metals are defects and stress state. These factors are especially critical in additively manufactured materials, as components made by additive manufacturing (AM) can have complex shapes that result in the material being subjected to multiaxial stresses under load, and these materials may also contain internal porosity due to AM processing. This study experimentally investigates the effects of both internal pores and stress state on the ductile failure behavior of laser powder bed fusion additively manufactured 316L stainless steel through the introduction of intentional penny-shaped pores of varying size at the center of samples whose geometries result in different stress states. It was found that strain to failure depended strongly on stress triaxiality until a large pore size with a diameter of 1200 µm (4% cross-sectional area of the sample gauge sections), while strain to failure was independent of stress triaxiality, and only a function of pore diameter, with larger pores (9% cross-sectional area or larger).

影响韧性金属失效行为的两个主要变量是缺陷和应力状态。这些因素在增材制造材料中尤为关键，因为通过增材制造（AM）制成的部件可能具有复杂的形状，从而导致材料在负载下承受多轴应力，并且由于AM加工，这些材料也可能包含内部孔隙。本研究通过在样品中心引入不同大小的有意小孔形孔隙来研究内部孔隙和应力状态对激光粉末床熔合制造的316L不锈钢延性破坏行为的影响。压力状态。