Investigation of the Effect of Drill Bit Feature on Hole Surface Quality and Tool Wear

Murat Kiyak

doi:10.24012/dumf.1002180

Abstract

Drilling operations have an important role in manufacturing industries and the application range is about 33% among the machining methods. In drilling processes, hole quality is affected by workpiece material, drilling parameters, drill diameter, drill bit features. In this study, the surface quality of the hole and the drill bit wear were investigated experimentally when drilling AISI 1040 steel and Al7075 aluminum workpieces with twist drills. Three different types of twist drill bits (polished, rolled and TiN coated) with diameters of 8 mm and 10 mm were used for drilling. Hole surface roughness was investigated at the hole entry and hole exit. While revealing the surface quality change at the hole entry-exit, the effect of the drill feature difference on the surface quality has been tried to be determined. In general, hole surface quality decreased with increasing drill bit diameter when drilling both materials. The lowest surface roughness values were obtained in the use of TiN coated drill bits. Drill bit wear was also measured in the study, and it was seen that the drill bit wear increased with increasing drill bit diameter. The least drill bit wear value was also observed in TiN coated drill bits.

Highlights

Today, in the manufacturing industry, the manufacturing methods are quite advanced, the drilling method is still one of the most widely used machining methods, and its application rate is about 33% among all machining methods
Hole surface roughness was measured from both the hole entrance and hole exit to determine the effects of drilling parameters and tool wear
Hole surface quality decreased with increasing drill bit diameter when drilling both materials

Summary

Introduction

In the manufacturing industry, the manufacturing methods are quite advanced, the drilling method is still one of the most widely used machining methods, and its application rate is about 33% among all machining methods. The most important parameters in drilling are cutting speed and feed. These parameters directly affect the cutting temperature, cutting forces, tool wear, hole surface quality and hole geometry. Hole quality depends on various conditions such as cutting speed, feed, drill bit geometry and material, drill bit manufacturing characteristics, and workpiece material. Material and the technological properties of the drill bit have a significant impact on hole surface quality. Along with these factors affecting the surface quality, drilling parameters and the resistance of the workpiece to machining will cause tool wear

Methods

Results

Conclusion