[15P-T4-03] Effects of Post-HIP Treatment on the Microstructure of Cr-Al Alloy Target
Keywords:High Corrosion Resistance Properties, Cr-Al Alloy Target, Canning HIP(Hot Isostatic Pressing), CIP(Cold Isostatic Pressing), Sinter-HIP
Hot Isostatic Pressing (HIP) is a process that uses a unique combination of higher pressure and temperature to produce materials and parts with significantly better properties than those made by other methods.
This study aims to manufacture Cr-Al alloy target material for high corrosion resistance coating of Accident tolerant fuel cladding. In this study, Cr-Al alloy targets (3 inches) were manufactured and analyzed through Siter-HIP and Canning-HIP processes. This process can effectively prevent the formation of chromium oxide or other compounds to form stable crystal growth. Cr-Al alloy has a very high reaction at high temperature, which easily retains some impurity elements of nitrogen and oxygen in the Cr target and generates intermetallic compounds, which directly affects the purity and quality during the coating process.
In this study, an electrochemical corrosion method was used to observe the microstructure. The electrolyte ratio of oxalic acid and deionized water is 2:3. Electric etching is performed at a constant of 0.5 A for 30 seconds. The prepared specimens were analyzed for microstructure and structure through XRD, FE-SEM (EBSD), and TEM.
The microstructure of the fabricated samples is very dense, homogeneous, and slightly porous, so there are no connected pores or cracks. This demonstrates that the canning-HIP process can produce extremely dense Cr-Al alloy targets. Additionally, the OM microstructure of grain morphology and grain boundaries is very clear, and both vertical and horizontal specimens show equiaxed grains and non-oriented crystallization. The microstructure and mechanical properties of the sinter-HIP and canning-HIP targets do not show directional differences. Smaller particles and uniform densification of the sputtering target can improve the efficiency of the coating process.
Acknowledgment: This work was supported by the National Research Foundation of Korea's core technology development project to improve operating nuclear power plant safety, No. RS-2022-00144432.
This study aims to manufacture Cr-Al alloy target material for high corrosion resistance coating of Accident tolerant fuel cladding. In this study, Cr-Al alloy targets (3 inches) were manufactured and analyzed through Siter-HIP and Canning-HIP processes. This process can effectively prevent the formation of chromium oxide or other compounds to form stable crystal growth. Cr-Al alloy has a very high reaction at high temperature, which easily retains some impurity elements of nitrogen and oxygen in the Cr target and generates intermetallic compounds, which directly affects the purity and quality during the coating process.
In this study, an electrochemical corrosion method was used to observe the microstructure. The electrolyte ratio of oxalic acid and deionized water is 2:3. Electric etching is performed at a constant of 0.5 A for 30 seconds. The prepared specimens were analyzed for microstructure and structure through XRD, FE-SEM (EBSD), and TEM.
The microstructure of the fabricated samples is very dense, homogeneous, and slightly porous, so there are no connected pores or cracks. This demonstrates that the canning-HIP process can produce extremely dense Cr-Al alloy targets. Additionally, the OM microstructure of grain morphology and grain boundaries is very clear, and both vertical and horizontal specimens show equiaxed grains and non-oriented crystallization. The microstructure and mechanical properties of the sinter-HIP and canning-HIP targets do not show directional differences. Smaller particles and uniform densification of the sputtering target can improve the efficiency of the coating process.
Acknowledgment: This work was supported by the National Research Foundation of Korea's core technology development project to improve operating nuclear power plant safety, No. RS-2022-00144432.