Evaluation of input process parameters in turning operations affecting the thread cutting operation on NIMONIC 80A for dental implant device

Abstract

NIMONIC 80A, a nickel-chromium-based superalloy, is renowned for its outstanding mechanical strength, thermal stability, and resistance to corrosion, making it indispensable in high-stress applications like nuclear boilers, gas turbines, and dental implants. This study explores its machining performance in turning and thread-cutting processes, with a focus on precision and biocompatibility for dental implant applications. An L₉ orthogonal array guided the experiments, varying spindle speed, feed rate, and depth of cut to examine their effects on material removal rate (MRR), chip thickness, and surface roughness (SR). Key findings indicated that higher spindle speeds and greater depths of cut enhanced MRR and chip thickness but negatively impacted SR. Optimal parameters to minimize SR were identified and applied to thread-cutting operations. Threaded samples underwent scanning electron microscopy (SEM) analysis to assess microstructural integrity and surface quality. The study established that a spindle speed of 1250 RPM, a feed rate of 0.3 mm/rev, and a depth of cut of 0.8 mm achieved the best MRR, while slower speeds and lower feed rates improved SR. The threaded components exhibited superior dimensional accuracy and surface properties, making them highly suitable for dental implant applications. Moreover, the absence of built-up edges at elevated spindle speeds improved machining efficiency. This research underscores the critical role of optimized machining parameters in producing high-quality threads for NIMONIC 80A, advancing its use in precision biomedical manufacturing and enhancing its application in dental implants.