Microstructural damage analysis during drilling in composite laminate with and without smart magneto-elastomer...

Area of Science:

• Materials Science
• Mechanical Engineering
• Manufacturing Processes

Background:

• Carbon fiber reinforced polymer (CFRP) is a popular composite material with excellent mechanical properties.
• Drilling is a common machining operation for CFRP, but delamination caused by thrust force is a critical issue.
• Minimizing thrust force during CFRP drilling is essential for high-end applications.

Purpose of the Study:

• To investigate the effectiveness of a magnetorheological elastomer (MRE)-based isolator in reducing drilling-induced thrust force in CFRP.
• To analyze the impact of fiber orientation (unidirectional vs. bidirectional) on thrust force reduction.
• To evaluate the microstructural changes in drilled holes using scanning electron microscopy.

Main Methods:

• Utilizing an MRE-based isolator during the drilling of both unidirectional and bidirectional CFRP.
• Developing an empirical model to describe thrust force variations in relation to the final layers of CFRP.
• Conducting microstructural analysis of drilled holes with a scanning electron microscope.

Main Results:

• MRE-based isolators significantly reduce thrust force in CFRP drilling.
• The thrust force reduction is consistent across both unidirectional and bidirectional CFRP composites.
• Empirical model accurately predicts thrust force variations, correlating with microstructural observations.

Conclusions:

• MRE-based isolators are effective in mitigating drilling thrust force and improving hole quality in CFRP.
• Fiber orientation does not significantly alter the percentage of thrust force reduction achieved by MRE isolators.
• Microstructural evaluation confirms the analytical findings and highlights the benefits of MRE isolators for CFRP drilling.