Secondary Creep Analysis of FG Rotating Cylinder with Exponential, Linear and Quadratic Volume Reinforcement

Area of Science:

• Materials Science and Engineering
• Mechanical Engineering
• Solid Mechanics

Background:

• Creep is a critical time-dependent deformation under stress and elevated temperatures, impacting the service life of high-temperature components like jet engines and boiler tubes.
• Secondary or steady-state creep is of significant engineering interest due to its constant creep rate and its role in material failure prediction and design limitations.
• ASME Boiler and Pressure Vessel Code addresses creep by providing guidelines for maximum allowable stresses, often based on a 1% creep deformation limit over 100,000 hours.

Purpose of the Study:

• To investigate the secondary creep behavior of functionally graded (FG) thick-walled rotating cylinders subjected to internal and external pressures.
• To analyze the influence of different volume reinforcement profiles (exponential, linear, quadratic) of SiCp ceramic in an aluminum metal matrix on creep stresses and strains.
• To provide insights for designing advanced FG materials with enhanced creep resistance for high-temperature applications.

Main Methods:

• Conducted a secondary creep analysis on a thick-walled rotating cylinder model made of functionally graded material.
• Employed exponential, linear, and quadratic volume reinforcement functions for the ceramic phase (SiCp) within the metal matrix (Al) in the radial direction.
• Obtained closed-form solutions for stress and strain rates in radial and tangential directions, analyzing the FG cylinder's response under pressure and centrifugal forces.

Main Results:

• Quantified secondary creep stresses and strains for FG cylinders with varying reinforcement profiles.
• Demonstrated the significant effect of volume reinforcement distribution on the creep response of the FG cylinder.
• Provided graphical comparisons of steady-state creep stresses and strains under different reinforcement strategies.

Conclusions:

• The study successfully analyzed secondary creep in FG rotating cylinders, highlighting the impact of reinforcement profiles on material behavior.
• Findings offer valuable data for engineers to predict component life and design superior creep-resistant functionally graded materials.
• The developed analytical model provides a foundation for further research into advanced materials for extreme operating conditions.