Interface stress transfer model and modulus parameter equivalence method for composite materials embedded with...

Area of Science:

• Materials Science
• Mechanical Engineering
• Composite Materials

Background:

• Accurate structural dynamic modeling of shape memory alloy composites (SMAC) relies on understanding their constitutive models and modulus parameters.
• The dynamic characteristics and modeling accuracy of SMAC are directly influenced by these foundational properties.

Purpose of the Study:

• To propose a homogenization method for SMAC that incorporates interfacial phases.
• To mathematically model and derive stress distributions within the fiber, interfacial, and matrix phases of SMAC.
• To determine the macroscopic effective modulus and stress characteristics of SMAC.

Main Methods:

• A homogenization method considering interfacial phases for SMA composites.
• Physical modeling of interface stress transfer in three-phase cylinders.
• Mathematical derivation of axial and shear stresses for each phase (SMA fiber, interfacial phase, matrix phase).

Main Results:

• The study determined the macroscopic effective modulus and phase-specific stress characteristics of SMAC.
• Findings highlight the critical role of volume fraction and tensile pre-strain in interphase stress transfer at elevated temperatures.
• Maximum axial stress in the SMA fiber phase reached 705.05 MPa at 5% pre-strain and 1000 MPa at 10% volume fraction.

Conclusions:

• The developed homogenization method and stress expressions accurately predict the effective modulus of SMAC.
• Experimental verification confirms the theoretical calculation method's accuracy.
• This work provides a foundation for advanced dynamic modeling of SMAC structures.