Investigation of burr formation in Ti-6Al-4V drilling

To enhance the efficiency of aircraft structural assemblies, aircraft manufacturers are striving to implement a one-way assembly drilling strategy. This strategy negates the necessity for structures to be disassembled for cleaning and deburring interfaces subsequent to drilling. The implementation of this innovative strategy presents a significant industrial challenge, as it must address several technical issues, including the management of burrs at stack interfaces. It is imperative that these burrs be monitored, as they have the potential to negatively impact the fatigue strength of assemblies. Despite the extensive research conducted on burrs, the underlying mechanisms of their formation remain poorly understood, particularly with regard to the thermal phenomena that occur during the cutting process. The present study employs an interrupted experimental design, complemented by thermal measurements, to investigate the burr formation during the drilling process of Ti-6Al-4V alloy. Additionally, metallographic analyses are conducted to examine the alteration in microstructure in the vicinity of the hole surface. The results obtained facilitate a more in-depth comprehension of the processes that occur during burr formation, which may potentially impact the assembly performance. • Interrupted tests allow to estimate deformed material volume during burr formation. • Burr formation comes with in-depth metallurgical modification of machined surfaces. • Temperature rise during drilling process is highly correlated with burr and tool wear.