Failure characteristics and wear evolution of coated carbide tools with different geometric structures in turning GH4169 nickel-based superalloys

The GH4169 nickel-based superalloy, known for its exceptional high-temperature strength and creep resistance, is extensively utilized in the aerospace and energy sectors. Despite these advantageous properties, machining GH4169 poses significant challenges due to its high plasticity, cutting forces and elevated temperatures, which lead to rapid tool wear and potential surface integrity issues. This study investigates these challenges by selecting inserts with different chip breaker structures to examine tool wear during the turning of GH4169 alloy. The wear mechanisms and catastrophic failure mechanisms of different tools were explored, elucidating the wear evolution process during turning. The study focused on the impact of different chip breaker structures on tool wear and turning performance. Results indicated that the high plasticity and elevated cutting temperatures of nickel-based superalloy primarily caused catastrophic tool failure in the form of chipping. The geometric structure of the tools, particularly the chip breaker, significantly influenced chip formation and breakage, thereby affecting the thermal state and wear resistance of the tools. Additionally, a theoretical model of the turning profile height was developed, and the surface integrity of the machined surface was comprehensively analyzed. This research provides insights into optimizing tool design and machining parameters for improved efficiency in machining nickel-based superalloys.