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This study evaluates fatigue properties of copper (Cu) alloy Cu7.2Ni21.8Si1Cr produced by selective laser melting technology (SLM). This technology belongs to additive manufacturing or 3D printing technologies and allows produce metal parts with complicated shapes in short production time and without the need to use expensive molds or large material waste. As the SLM technology is still under intensive research, the production process is not optimized for wide range of materials (most of studies were focused on titanium or aluminum alloys). Low quality of SLM materials is mainly connected with production defects caused by big temperature gradients during production. The SLM material is subjected to fatigue bending tests, which are supplemented by acoustic emission (AE) measurement and fractography analysis. By AE is possible to analyze fatigue behavior in detail and determine different fatigue stages and mechanism of crack propagation. After verification experiments, it is also possible to predict the remaining fatigue life. All results are compared with fatigue properties of conventionally produced Cu alloy AMPCOLOY® 944 (Cu7Ni2Si1Cr) using standard S-N curves. The fatigue life of SLM material is slightly worse than we can observe in conventionally produced materials and AE results suggest that there is different mechanism of crack propagation. As expected, the fractography study shows there is big amount of production defects (mainly pores) in SLM material and the crack origins are located near them.
Keywords: Fatigue, Cu alloy, Selective Laser Melting, Acoustic Emission© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.