Cutting Parameter Optimization in Finishing Milling of Ti-6Al-4V Titanium Alloy under MQL Condition using TOPSIS and ANOVA Analysis

V C Nguyen,D H Tien,T D Nguyen

doi:10.48084/etasr.4015

Abstract

Titanium and its alloys give immense specific strength, imparting properties such as corrosion and fracture resistance, making them the right candidate for medical and aerospace applications. There is a wide range of engineering applications that use titanium alloys in a variety of forms. The cost of these alloys is slightly higher in comparison to other variants due to the problematic extraction of the molten process. To reduce costs, titanium alloy products could be made by casting, isothermal forging, radial swaging, or powder metallurgy, although these techniques require some kind of finishing machining process. Titanium and its alloys are difficult to machine due to skinny chips leading to a small cutting tool-workpiece contact area. The thermal conductivity of titanium alloys is too low and the stress produced is too large due to the small contact area, which results in very high cutting temperatures. This paper deals with the experimental study of the influence of the Minimum Quantity Lubricant (MQL) environment in the milling of Ti-6Al-4V alloy considering the optimization of surface roughness and production rate. Taguchi-based TOPSIS and ANOVA were used to analyze the results. The experimental results show that MQL with vegetable oil is successfully applied in the milling of Ti-6Al-4V. The research confirms the suitability of TOPSIS in solving the Multiple Criteria Decision Making (MCDM) issue, by choosing the best alternative at Vc=120m/min, fz=0.065mm/tooth, and ap=0.2mm, where the surface roughness and material removal rate are 0.41µm and 44.1492cm3/min respectively. Besides, ANOVA can be used to predict the best parameters set in the milling process based on the regression model. The parameters predicted by ANOVA analysis do not coincide with any implemented parameters

Highlights

According to the thermophysical properties at elevated temperatures, titanium alloy Ti-6Al-4V is considered as the best material to manufacture parts in medical or euro space industry [1, 2]
Minimum Quantity Lubricant (MQL) with vegetable oil is successfully applied in the face milling of Ti-6Al-4V
The best solution chosen by TOPIS is (Vc=120m/min, fz=0.065mm/tooth, and ap=0.2mm), where the surface roughness and the material removal rate are 0.41μm and 44.1492 cm3/min respectively

Summary

Introduction

According to the thermophysical properties at elevated temperatures, titanium alloy Ti-6Al-4V is considered as the best material to manufacture parts in medical or euro space industry [1, 2]. Due to the harmful effects of WMF to the operator’s health and environment, reducing MWF consumption is always considered. In this aspect, dry machining and Minimum Quantity Lubricant (MQL) are two of the most effective alternatives. The research showed the encouraging results where the MQL environment leads to the significant reducing of tool wear and surface roughness mainly through the declining of the temperature in cutting area and the change of the interaction between chip-tool and tool-workpiece during machining. Authors in [12] studied the grinding of Ti6Al-4V titanium alloy and the effects of different lubrication conditions on the surface quality. The MQL technique was applied in this study work to replace conventional lubricants in the milling process

Methods

Discussion

Conclusion