Ultrafine grained Mg-1Zn-1Mn-0.3Zr alloy and its corrosion behaviour

Purpose: The goal of this paper is to present the corrosion properties of the ultrafine grained Mg-1Zn-1Mn-0.3Zr bulk alloy after surface modification during HF and NaHCO3 treatment. Design/methodology/approach: An ultrafine grained Mg-1Zn-1Mn-0.3Zr bulk alloy was synthesized by consolidating mechanically alloyed powders. The phase and microstructure analysis was carried out using X-ray diffraction, scanning electron microscopy and the properties were measured using corrosion testing equipment. Findings: The sintering of Mg-1Zn-1Mn-0.3Zr powders led to the formation of bulk material with an average grain size of about 73 nm. Ultrafine grained Mg-1Zn-1Mn-0.3Zr alloy was more corrosion resistant than microcrystalline Mg. Practical implications: The results showed an improved corrosion resistance of HF and NaHCO3 treated Mg-1Zn-1Mn-0.3Zr alloy in Ringer solution compared with the untreated sample. The corrosion rate of treated samples followed the order HF