Effect of ultrasonic nanocrystal surface modification on the microstructure and martensitic transformation of selective laser melted nitinol

CA Biffi, P Bassani, M Nematollahi… - Materials, 2019 - mdpi.com
Materials, 2019mdpi.com
Nitinol has significant potential for biomedical and actuating-sensing devices, thanks to its
functional properties. The use of selective laser melting (SLM) with Nitinol powder can
promote novel applications aimed to produce 3D complex parts with integrated functional
performances. As the final step of the production route, finishing processing needs to be
investigated both for the optimization of the surface morphology and the limit alteration of the
Nitinol functional properties. In this work, the effect of an advanced method of surface …
Nitinol has significant potential for biomedical and actuating-sensing devices, thanks to its functional properties. The use of selective laser melting (SLM) with Nitinol powder can promote novel applications aimed to produce 3D complex parts with integrated functional performances. As the final step of the production route, finishing processing needs to be investigated both for the optimization of the surface morphology and the limit alteration of the Nitinol functional properties. In this work, the effect of an advanced method of surface modification, ultrasonic nanocrystal surface modification (UNSM), on the martensitic transformation and microstructure of SLM built Ni50.8Ti49.2 (at.%) was investigated. Scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry indicated that the UNSM process can generate stress-induced martensite, at least partially suppressing the martensitic transformation. The microhardness profile indicates that the UNSM process can affect the mechanical properties of the SLMed Nitinol sample in a range of up to approximately 750 μm in depth from the upper surface, while electron backscatter diffraction analysis highlighted that the initial austenitic phase was modified within a depth below 200 μm from the UNSMed surface.
MDPI
以上显示的是最相近的搜索结果。 查看全部搜索结果