Influences of tool structure, tool material and tool wear on machined surface integrity during turning and milling of titanium and nickel alloys: a review

Titanium and nickel alloys have been used widely due to their admirable physical and mechanical properties, which also result in poor machinability for these alloys. Improvement of surface integrity of titanium and nickel alloys is always a challengeable subject in the area of manufacture. Besides the cutting parameters and cutting environments, the structure and material of cutting tools are also the most basic factors that govern the machined surface integrity. This review paper provides an overview of the machined surface integrity of titanium and nickel alloys with reference to the influences of tool structure, tool material, as well as tool wear. Surface integrity mainly covers geometrical characteristics, microstructure alterations and mechanical properties of the machined surface. Influences of cutting tool parameters on above characteristics of machined surface integrity are reviewed respectively, and there are many different types of surface integrity problems reported in the literatures. However, the current research on the effects of tool parameters on machined surface integrity mainly depends on practical experiments or empirical data, a comprehensive and systematic modeling approach considering the process physics and practical application is still lacking. It is concluded that further research for the influence of tool parameters on machined surface integrity should consider the requirements of service performance (e.g. fatigue life) for machined components. It is vital important to establish the mapping relationships among the cutting tool parameters, machined surface integrity, and the service performance of machined components.

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