Corrosion resistance mechanisms of detonation sprayed Fe-based amorphous coating on AZ31B magnesium alloy

Effect of Minor Mo Addition on Microstructure and Corrosion Resistance of High-Velocity Air Fuel-Sprayed Fe-Based Amorphous Coatings

“…Additionally, the HVAF process has great potential for the preparation of amorphous coatings because the cooling rate is fast enough (about 10 7 K/s) to prevent the remote diffusion of atoms and To evaluate the impact of a small Mo addition on the corrosion resistance of Febased coatings, potentiodynamic polarization behaviors and EIS tests were performed on FeNbBSiCrNi and FeNbBSiCrNiMo coatings, and the results are shown in Figure 6. The self-corrosive potential (E corr ) responds to the ease with which the material can be corroded, and the self-corrosive current density (I corr ) responds to the actual corrosion rate of the material [26]. From Figure 6a, it can be seen that with the addition of minor amounts of Mo, the E corr of the Fe-based coatings increased from −597 mV to −491 mV, and the I corr decreased from 4.44 µA/cm 2 to 3.78 µA/cm 2 .…”

Time-Dependent Passivation Performance of Plasma Sprayed FeCrMoCBY Amorphous Coating

“…In borate buffer solution, it is noted that anions will unavoidably influence the production and dissolution of passive film, thus possibly leading to two time constants regarding film growth reaction and the anion corrosion rate. Additionally, the defects, including elemental segregation, pores and cracks, existent in the coating are disposed to induce galvanic corrosion [39], resulting in the phenomenon of two time constants at the initial passivation period. However, the corrosion resistance dominated by enhanced passivity during the later passivation period will be remarkably promoted owing to the unceasing growth of a denser and less faulty passive film with the prolongation of passivation time.…”

Microstructure and Corrosion Resistance of an HVAF-Sprayed Al-Based Amorphous Coating on Magnesium Alloys

“…are suitable for Mg and its alloys [4][5][6][7][8]. Importantly, recent studies [9][10][11] have shown that thermal spray coatings have an enormous potential to improve the surface properties of Mg alloys.…”

“…The high-velocity air/oxygen fuel (HVAF/HVOF) spray is popular due to its flexibility, cost-effectiveness, and superior coating quality [12][13][14]. Different coating materials, such as Ni-based alloys [4,15], Co-P [6], Mg-O [7] composite materials, and Fe-based amorphous alloys [9], were sprayed on Mg alloys using the HVAF/HVOF process to achieve good corrosion resistance performance. The coating materials could keep the original structure and mechanical properties due to the fact that the HVAF/HVOF spray exhibits ultra-high flying velocity and relatively low temperature [16,17].…”