Paper Details

Name: Dharmpal Deepak
Country: India

Year: 2015
Volume: Volume-2, Issue-2 (July-December)
Page Number: 62-72

The present research paper investigates the creep deformation and stress
distribution behavior of rotating functionally graded metal matrix composite
(FGMMC) discs operating under elevated temperature conditions. Functionally
graded materials (FGMs), particularly aluminum matrix composites reinforced with
silicon carbide particles, have attracted significant attention in aerospace,
automotive, and high-temperature engineering applications because of their
superior thermal resistance, high strength-to-weight ratio, and improved creep
resistance. The study focuses on the theoretical modeling and analysis of creep
behavior in rotating composite discs subjected to thermo-mechanical loading and
material composition gradients. A detailed review of classical creep theories,
including Norton’s law, Bailey–Norton law, time hardening, and strain hardening
approaches, has been incorporated to establish the constitutive framework for creep
analysis. The influence of threshold stress, stress exponent, activation energy, and
reinforcement distribution on creep response has also been examined. The
functionally graded characteristics of the composite disc are considered through
gradual variation of reinforcement concentration along the radial direction, which
helps in minimizing stress concentration and enhancing structural performance. The
analysis demonstrates that creep strain rate, radial stress, tangential stress, and
displacement distribution are strongly influenced by rotational speed, temperature
gradient, reinforcement geometry, and material gradation profile. It is observed that
functionally graded composite discs exhibit improved creep resistance and reduced
stress concentration as compared to homogeneous discs. The study further
highlights the significance of optimized reinforcement distribution for enhancing the
service life and reliability of rotating components operating in severe thermal
environments. The outcomes of this investigation may provide useful guidelines for
the design and development of advanced rotating machinery components made
from FGMMCs.