Thermal Processing Map and Microstructure Evolution of Inconel 625 Alloy Sheet Based on Plane Strain Compression...

Area of Science:

• Materials Science
• Metallurgy
• Mechanical Engineering

Background:

• Understanding the deformation behavior of Inconel 625 is crucial for optimizing its processing.
• Dynamic recrystallization (DRX) significantly influences the microstructure and mechanical properties of alloys during hot working.

Purpose of the Study:

• To investigate the hot deformation behavior of Inconel 625 alloy sheets.
• To establish a constitutive equation and develop processing maps.
• To identify optimal hot working parameters and understand recrystallization mechanisms.

Main Methods:

• Plane strain compression tests were conducted at various temperatures and strain rates.
• Constitutive equations were developed using peak stress data.
• Processing maps were generated to identify stable and unstable deformation regions.
• Electron backscattered diffraction (EBSD) was used for microstructural analysis.

Main Results:

• The effective stress-strain curves displayed typical dynamic recrystallization (DRX) characteristics.
• Increasing temperature and decreasing strain rate enhanced the softening effect.
• An unstable deformation region was identified at 950-960 °C and 0.007-0.05 s⁻¹.
• The optimal hot working conditions were determined to be 1020-1060 °C at 0.005-0.03 s⁻¹.
• Higher temperatures and lower strain rates promoted recrystallization, with discontinuous dynamic recrystallization (DDRX) dominating at low strain rates.

Conclusions:

• The study successfully established a constitutive equation with an average error of 5.68%.
• Processing maps provide valuable insights into controlling the microstructure of Inconel 625 during hot working.
• The identified optimal conditions and understanding of recrystallization mechanisms can guide the rolling process optimization and microstructure control for Inconel 625 alloy sheets.