Shape Memory Alloys Applied to Automotive Adaptive Aerodynamics

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Mechanics

Background:

• Shape memory alloys (SMAs) possess unique thermomechanical properties, driving their increasing adoption in automotive and aerospace sectors.
• Accurate simulation of SMA behavior is crucial for designing complex components and systems.
• Existing models may not fully capture the intricate thermomechanical responses of SMAs under various conditions.

Purpose of the Study:

• To develop and numerically implement a comprehensive constitutive model for simulating the thermomechanical behavior of shape memory alloys.
• To integrate this model as a user subroutine within the Abaqus/Standard finite element code.
• To validate the model's capability in predicting the performance of SMA-based systems.

Main Methods:

• A constitutive model was developed, utilizing temperature and strain as control variables to capture shape memory and superelastic effects.
• The model was implemented as a user subroutine (UMAT) for Abaqus/Standard finite element analysis.
• A skid plate system utilizing bistable actuators with SMA springs was designed and simulated to demonstrate the model's application.

Main Results:

• The numerical implementation successfully simulated the thermomechanical behavior of SMAs, accounting for material property variations.
• The skid plate system simulation demonstrated effective load generation through SMA state changes driven by temperature distribution.
• The actuator's performance in switching configurations and maintaining stability was successfully assessed.

Conclusions:

• The proposed comprehensive constitutive model provides a robust tool for simulating the thermomechanical behavior of shape memory alloys.
• The successful implementation in Abaqus/Standard allows for the analysis of complex components and systems incorporating SMAs.
• The study confirms the significant potential of SMAs in advanced engineering applications, particularly when coupled with accurate simulation techniques.