Acta Metallurgica Sinica (English Letters) ›› 2019, Vol. 32 ›› Issue (8): 1007-1014.DOI: 10.1007/s40195-019-00896-1

Special Issue: 2019年腐蚀专辑-2

• Orginal Article • Previous Articles     Next Articles

Improved Corrosion Resistance of Selective Laser Melted Ti-5Cu Alloy Using Atomized Ti-5Cu Powder

Ying Han1, Hong-Rui Wang1, Yun-Dong Cao1, Wen-Tao Hou2, Shu-Jun Li2   

  1. 1 School of Electrical Engineering, Shenyang University of Technology, Shenyang 110870, China
    2 Titanium Alloy Laboratory, Institute of Metal Research,Chinese Academy of Sciences, Shenyang 110016, China
  • Received:2018-12-16 Online:2019-08-10 Published:2019-07-08

Abstract:

The different types of metal powder used for selective laser melting (SLM) process would cause distinct corrosion behavior due to the uniformity of the obtained microstructure. The SLM-produced Ti-5Cu alloy using atomized Ti-5Cu metal powder (SLMed Ti-5Cu) in this work reveals a relatively uniform microstructure with overwhelming acicular α/α′ phase and shows great advantages on corrosion resistance compared with the SLM-produced Ti-5Cu alloy using the mixture powder (SLMed-M Ti-5Cu). The effect of the micro-galvanic cells decreases due to the undetectable Ti2Cu phase in the microstructure of the SLMed Ti-5Cu. An apparent passivation behavior was observed for SLMed Ti-5Cu instead of severe pitting phenomenon for the SLMed-M Ti-5Cu. The charge transfer resistance of SLMed Ti-5Cu in this work is 10.09?±?2.63 MΩ cm2, which is significantly higher than that of SLMed-M Ti-5Cu (4.76 MΩ cm2). The above result indicates the atomized Ti-5Cu powder plays an important role in the formation of the uniform microstructure of SLMed product, thereby enhancing its corrosion resistance in Hank’s solution at 37 °C.

Key words: Selective laser melting, Corrosion behavior, Uniform microstructure, Ti-5Cu, Passivation, Polarization resistance