as built surface layer characterization and fatigue behavior of dmls ti6al4v

Abstract Direct Metal Laser Sintering (DMLS) is a powder bed fusion technology used in the fabrication layer-by-layer of metallic parts directly from a CAD file. Since the fatigue behavior of DMLS Ti6Al4V is strongly influenced by the surface roughness of the as-built surface, fatigue tests were performed on smooth specimens produced with different orientations with respect to build using an EOS M 290 system. A SEM investigation and roughness measurements of the test surfaces were used to interpret the surface roughness as the contribution of i) roughness induced due to solidification of the melt pool (primary roughness); ii) roughness induced by partly melted powder particles (secondary roughness). Surface roughness modification from the as-built state by manual grinding was also investigated in fatigue and found to give a limited improvement. On the other hand, surface machining improves considerably the fatigue strength with respect to both the as-built condition and the manually ground condition

The Influence of the Structure on the Fatigue Properties of Al-Mg Cast Alloy

The article will be focused on monitoring the influence of the structure on the fatigue properties of aluminium alloys for the casting of type Al-Mg. As an experimental material were used aluminium alloys EN AC 51200 and EN AC 51500, supplied in a cast state without a heat treatment. They were produced by the continuous casting method. These alloys were selected on the basis of the chemical composition, where the content of most alloying elements is comparable, only in the case of the concentration of magnesium are these alloys significantly different. Fatigue properties of aluminium alloys were tested by three-point bending cyclic loading. The fracture surface of the testing sample was examined using scanning electron microscopy (SEM), where samples were observed on various stages of the fatigue process, their characteristics and differences of fracture surfaces

The Influence of the Structure on the Fatigue Properties of Al-Mg Cast Alloy

The article will be focused on monitoring the influence of the structure on the fatigue properties of aluminium alloys for the casting of type Al-Mg. As an experimental material were used aluminium alloys EN AC 51200 and EN AC 51500, supplied in a cast state without a heat treatment. They were produced by the continuous casting method. These alloys were selected on the basis of the chemical composition, where the content of most alloying elements is comparable, only in the case of the concentration of magnesium are these alloys significantly different. Fatigue properties of aluminium alloys were tested by three-point bending cyclic loading. The fracture surface of the testing sample was examined using scanning electron microscopy (SEM), where samples were observed on various stages of the fatigue process, their characteristics and differences of fracture surfaces