Advances in the Experimental Research on the Surface Integrity in the Cutting of Titanium Alloy
Authors: Huang Ruifang , Li Guohe , Zhao Xutao , Qiao Qingrui , Pu Junjie 
Published: December 2024

Background:
Titanium alloy, as a high-strength alloy material, has been widely used in
aerospace and other fields due to its high specific strength, good corrosion resistance, super fracture
toughness, and fatigue resistance. However, its small elastic modulus, low thermal conductivity,
and strong chemical affinity result in high cutting forces and cutting temperatures during the
cutting process. Different thermo-mechanical coupling effects can change the surface structure,
composition, and mechanical properties of the workpiece and show different surface integrity.
This paper summarizes the recent progress in the experimental research on surface integrity in the
cutting of titanium alloy from four aspects, including surface roughness, microhardness, white layer,
and residual stress. It focuses on analyzing the experimental results about the influence of process
parameters, tool wear, and lubrication methods on surface integrity. The problems existing in
current research and the future development direction are pointed out in this article. It is helpful to
provide theoretical guidance for the machining of titanium alloy that meets the requirement of service
performance.

Introduction:
Surface integrity encompasses both geometric features and physical and mechanical
properties. Geometric features include surface roughness, surface morphology, and blade direction.
Extensive research has been conducted on surface roughness, microhardness, the white layer,
and residual stress. This article reviews recent advancements in experimental research on surface
integrity during titanium alloy cutting, focusing on the impact of cutting parameters, tool wear,
and lubrication methods. It also addresses current research challenges and suggests directions for
future development.

Method:
Scholars have conducted extensive research on surface roughness, microhardness, the
white layer, and residual stress using both experimental methods and finite element simulations.
Experiments are the primary method due to existing issues with finite element simulations, which
often suffer from low accuracy and poor reliability in studying surface integrity during titanium alloy
machining.

Results:
At present, a large amount of experiments have been conducted. However, due to the numerous
influencing factors and insufficient consideration of materials microstructure, the conclusions
of current research are not consistent. Therefore, it is necessary to conduct more in-depth
and systematic experimental research to clarify the influencing factors and the influence of cutting
parameters on surface integrity.

Conclusion:
There is a need for a deeper understanding of the physical and mechanical fundamentals
of surface integrity. Integrating experimental research with finite element simulations can enhance
the investigation of these mechanisms and improve predictions related to phase transformation,
microhardness, white layer, and residual stress. It is helpful to provide theoretical guidance
for the machining of titanium alloy that meets the requirement of service performance.