Enhancement of laser heating process by laser surface modification on Titanium alloy

A Q Zaifuddin,F Zulhilmi,M.H Aiman,M.M Quazi,M Ishak

doi:10.15282/jmes.15.3.2021.09.0653

Abstract

Titanium alloys are widely utilized in laser heating applications. However, it has poor optical properties due to low laser energy absorption. Nevertheless, a higher energy absorption can be realized by modifying the surface profile through increasing the surface roughness. In this present work, the laser surface modification (LSM) process was carried out to increase the roughness on surface of Ti6Al4V titanium alloy. Subsequently, the surface characterization and surface roughness were analysed by using the 3D optical microscope. The effect of laser power on the increment of surface roughness was investigated. It was revealed that an increase in laser power during LSM process could increase the surface roughness. The result shows that, the surface roughness of titanium alloy increased 27 times when modified with the highest laser power (27W) compared to the gritted surface. Furthermore, the modified surface by LSM will be heated using laser radiation in order to analyse the effect of surface roughness towards laser heating temperature. Depending on the value of the power during laser heating, the maximum temperature measured could be increased 27% corresponding to a gritted flat reference surface.

Highlights

Due to high strength, excellent corrosion resistance, and low density, titanium alloys have received much attention in recent years by utilizing laser heating process for related applications, especially in biomedical, aerospace, and aircraft [1,2,3]
The results of the samples pre and post laser surface modification (LSM) will be discussed. This lays the foundation for analyzing the effect of LSM on surface roughness of the titanium alloy
The sub-micron marks left by mechanical grinding on the surface of the samples can be seen. This ground surface of titanium alloy can be considered as relatively flat surface since the areal roughness is approximately 0.124 μm

Summary

INTRODUCTION

Excellent corrosion resistance, and low density, titanium alloys have received much attention in recent years by utilizing laser heating process for related applications, especially in biomedical, aerospace, and aircraft [1,2,3]. Many attempts to counter the issues regarding material's optical properties have been made and it was found that when modifying the surface layer, the laser energy absorptivity can be increased [5, 6]. Many approaches for preparing the surface have been studied, such as chemical etching, electrochemical machining (ECM), and laser surface modification (LSM). Among these methods, LSM owns several advantages. LSM owns a unique advantage which is the capability of fabricating surface texture with high complexity and accuracy [11, 12] Due to these merits, LSM has been widely used on different materials including titanium, stainless steel, ceramic and tungsten carbide [13]. Zaifuddin et al │ Journal of Mechanical Engineering and Sciences │ Vol 15, Issue 3 (2021)

MATERIALS AND METHODS

RESULTS

CONCLUSIONS