Applied Science and Engineering Progress
Influence of Novel Hydrofluoric Acid and Nitric Acid Etchants on Performance of Photochemical Machining of Ti-6Al-4V alloy for Biomedical Applications
Abstract
Photochemical machining (PCM) process is widely recognized for fabrication of precision engineering parts and components. This study examines the impact of novel hybrid Hydrofluoric Acid (HF) and Nitric Acid (HNO₃) etchant compositions on the PCM performance for cutting square-shaped (5 mm × 5 mm) cavities in Ti-6Al-4V alloy for biomedical component manufacturing. A total of 25 experiments were performed to determine the effects of etching composition and time on edge deviation (ED), material removal rate (MRR), and mean roughness depth (Rz). The novel HF-HNO₃ etchant enables precise PCM machining of Ti-6Al-4V, achieving minimum ED (29 µm) and Rz (1.82 µm) and maximum MRR (0.967 mg/min). The HF-HNO₃ composition was found to significantly affect etching kinetics, thereby affecting process productivity and the integrity of the machined surface. The findings provide deep insight into the etching behaviour of Ti-6Al-4V and establish process directions for applying PCM in the manufacturing of biomedical components.
Keywords
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DOI: 10.14416/j.asep.2026.04.008
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