Preparation and high‐temperature oxidation resistance of multilayer MoSi₂/MoB coating by spent MoSi₂‐based materials

Abstract

Spent MoSi 2 and MoB were used as raw materials to prepare multilayer MoSi 2 / MoB coating on molybdenum by the two-step method of slurry deposition and spark plasma sintering. The results showed dense MoSi 2 /MoB coating after sintering while penetrated cracks appeared in MoSi 2 coating due to coefficient of thermal expansion mismatch between the Mo substrate and coating. After the sintering of MoSi 2 /MoB coatings, MoB and Mo 2 B diffusion layers were formed between MoB transition layer and Mo substrate without defects, exhibiting good metallurgical bonding. The hightemperature oxidation behavior of coatings (1500°C) was also explored. After oxidation of 50 h at 1500°C, lowest mass gain (0.035 mg/cm 2 ) was obtained for MoSi 2 / MoB coating, and the oxide scale was dense and complete without voids, making the oxygen diffusion at elevated temperature inhibited. Compared with MoSi 2 coating under the same oxidation conditions, relatively thinner silica oxide scale was acquired by MoSi 2 /MoB coating because of the reduction of cracks, and the multilayer coating exhibits better anti-oxidation properties at high temperature.

Oxidation Behavior of Carbon Fibers in Ceramizable Phenolic Resin Matrix Composites at Elevated Temperatures

“…When the temperature reached 800 °C, a small amount of MoSi 2 reacted with oxygen to produce Mo 5 Si 3 and amorphous SiO 2 [ 37 , 38 ]. However, due to its amorphous state, no obvious SiO 2 peak was detected.…”

“…It can be seen from Figure 6 that the main component of both BP-0 and BP-15 at temperatures ranging from room temperature to 1400 • C was MoSi 2 , which indicates that the MoSi 2 in the composites was relatively stable while the boron phenolic resin itself pyrolyzed intensely at high temperatures. When the temperature reached 800 • C, a small amount of MoSi 2 reacted with oxygen to produce Mo 5 Si 3 and amorphous SiO 2 [37,38]. However, due to its amorphous state, no obvious SiO 2 peak was detected.…”

Enhanced oxidation resistance of HfB2‐SiC‐ZrSi2 coating at 1700°C through low‐loss film‐forming treatment

“…It is known that the formation process of the multiphase glass layer 17 coincides with composite oxidation‐induced self‐damage and disintegration of the coating structure that provides defense against oxygen 18 . The defects generated during this process can provide a pathway for oxygen diffusion and cause oxidation damage to the carbon matrix 19,20 . Our previous work 21,22 has proved that low‐loss film‐forming treatment (LFT) based on reduced film‐forming temperatures can significantly reduce oxidation losses 23–26 .…”

Study on High-Temperature Oxidation Behavior of Platinum-Clad Nickel Composite Wire

“…Scientists have produced a significant amount of research on high-temperature protection coatings of nickel and nickel alloys, including the selection of coating materials [7,8], coating preparation [9,10], coating modifications [11,12], properties [13,14], and oxidationresistance mechanisms [15,16]. These research results have promoted the development of high-temperature protection fields and also provided guidance for the development of this project.…”