Systematically Study the Tensile and Compressive Behaviors of Diamond-like Carbon

Area of Science:

• Materials Science
• Mechanical Engineering
• Computational Physics

Background:

• Diamond-like carbon (DLC) coatings are crucial for wear resistance and damping.
• Understanding DLC's mechanical behavior under varying conditions is vital for advanced applications.
• Temperature and density significantly influence DLC's mechanical properties, limiting current applications.

Purpose of the Study:

• To systematically investigate the deformation behaviors of diamond-like carbon (DLC) under varied temperatures and densities.
• To elucidate the impact of temperature and density on DLC's mechanical response during tensile and compressive loading.

Main Methods:

• Molecular dynamics (MD) simulations were employed to model DLC.
• Compression and tensile testing simulations were performed across a temperature range of 300 K to 900 K.
• DLC models with varying densities were analyzed.

Main Results:

• Increased temperature (300 K to 900 K) led to decreased tensile and compressive stress, and increased tensile and compressive strain.
• Young's modulus in tensile simulations showed higher temperature sensitivity in denser DLC models.
• Compressive deformation was dominated by Csp2-Csp3 transitions and relative slip, while tensile deformation involved Csp3-Csp2 transitions.

Conclusions:

• Temperature significantly affects the mechanical deformation of DLC, particularly tensile properties.
• DLC density influences the temperature sensitivity of Young's modulus during tensile stress.
• Specific atomic transitions (Csp3-Csp2 and Csp2-Csp3) and slip mechanisms govern DLC's response to different mechanical loads.