Heterogeneous Deformation of As-Built Nickel Alloy 625 with Checkered Columnar Grains at Different Strain Rates...

Area of Science:

• Materials Science
• Mechanical Engineering
• Additive Manufacturing

Background:

• Additive Manufacturing (AM) simulations require accurate material data.
• The Additive Manufacturing Benchmark Test Series (AM Bench) aims to provide this data.
• Nickel alloy 625 is a critical material in AM applications.

Purpose of the Study:

• To characterize the tensile behavior and microstructure of AM nickel alloy 625.
• To provide benchmark data for AM simulations.
• To investigate the relationship between microstructure and deformation.

Main Methods:

• Tensile testing at strain rates of 10⁻³ s⁻¹ and 10⁻² s⁻¹.
• Stereo digital image correlation (DIC) for strain measurement.
• Scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) for microstructural analysis.
• Nanoindentation with EBSD for localized mechanical properties.

Main Results:

• Observed heterogeneous deformation with crosshatch strain banding at both strain rates.
• Measured anisotropic deformation deviating from isotropic paths.
• SEM and EBSD revealed microstructural features influencing deformation.
• Nanoindentation showed variations in response based on grain orientation and location relative to laser tracks.

Conclusions:

• The microstructure of additively manufactured nickel alloy 625 significantly influences its anisotropic and heterogeneous deformation.
• DIC and advanced microscopy techniques are crucial for understanding AM material behavior.
• The AM Bench 2022 data provides valuable insights for AM process optimization and simulation accuracy.