Microstructure and Wear Property of ZrO2-Added NiCrAlY Prepared by Ultrasonic-Assisted Direct Laser Deposition

Abstract

For improving the wear properties of NiCrAlY, the 10 wt %, 20 wt % and 30 wt % ZrO2-added NiCrAlY samples were prepared by ultrasonic-assisted direct laser deposition, respectively. The results showed that the ultrasonic-assisted direct laser deposition can realize the ZrO2-added NiCrAlY preparation. Furthermore, due to the cavitation effect and agitation of the ultrasound in the molten pool, ultrasonic-assisted could make the upper surface of the samples smoother and flatter, and it also improved the microstructural homogeneity. The microstructure was mainly composed of columnar dendrites, and most of ZrO2 particles were located in the intergranular regions. The principal phase constituents were found to contain γ-Ni and t-NiZr2, and the amorphous (Ni, Zr) intermetallic phase generated, because of more rapid solidification after ultrasound assisted. The microhardness was improved slightly with the increase of ZrO2 contents, rising from 407.9 HV (10% ZrO2) to 420.4 HV (30% ZrO2). Correspondingly, wear mass loss was decreased with the maximum drop 22.7% of 30% ZrO2 compared to that of 10% ZrO2, and wear mechanisms were mainly abrasive wear with slightly adhesive wear. After applying ultrasound, the oxide islands in samples disappeared, and more ceramic particles were retained. Thus, the hardness and wear performance of the samples were improved.

Crack Inhibition and Performance Modification of NiCoCr-Based Superalloy with Y2O3 Nanoparticles by Laser Metal Deposition

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A Review on the Enhancement of Mechanical and Tribological Properties of MCrAlY Coatings Reinforced by Dispersed Micro and Nanoparticles

“…A successful approach to overcome this problem is utilizing laser deposition technology along with ultrasonic vibration. Yi et al [96] used a direct laser deposition technique under ultrasonic vibration for the preparation of ZrO 2reinforced NiCrAlY coatings. Prior to employing the ultrasound-assisted technique, the obtained specimens exhibited undesirable macroscopic morphology with numerous oxide scales at the surface, which were spalled during the cooling period.…”

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“…In 2020, Xie Tianhai et al did an experimental study on the removal of thermal barrier coatings via a plasma spraying method with abrasive water jets. The results showed that the erosion hole diameter and hole depth increased with the increase in abrasive concentration, jet pressure, punching time, and target distance, and the coating removal rate increased with the increase in abrasive hardness and particle size [23].…”