Femtosecond laser ablation behavior of diamond/SiC composites in different environments: air and dynamic water

Diamond/SiC composites exhibit excellent thermal conductivity, mechanical strength, and wear resistance, making them promising for high-performance applications. However, their inherent high hardness and brittleness present significant challenges during machining. Femtosecond laser processing, particularly with liquid assistance, enables high-quality machining with minimal heat-affected zones. Nonetheless, the coexistence of reinforcement and matrix phases with distinct thermal properties makes their ablation behavior highly complex. To clarify the mechanisms in different environmental conditions, femtosecond laser ablation experiments were performed in air and dynamic water. Herein, temperature evolution, groove profiles, surface morphology, and elemental composition were systematically analyzed. Results indicate that the dynamic water medium effectively suppresses local overheating of the SiC matrix, mitigating pit-like damage. Furthermore, dynamic water continuously removes ablation byproducts, reducing plasma shielding and improving laser energy transmission. As a result, deeper and cleaner grooves are achieved under water-assisted conditions. This work provides insights into environment-dependent laser–material interactions and supports optimized machining of ceramic composites.