This paper presents a study of the total cutting force used and selected parameters of the geometric structure of the surface (e.g., Sa, Sz) during the end milling process of NiTi alloy. The input parameters included are cutting speed (v_c), feed per tooth (f_z), and radial depth of cut (a_e). A Box–Behnken experimental design was employed to conduct the research. The obtained experimental results were utilized within the framework of a response surface methodology (RSM) to develop mathematical and statistical models capable of predicting cutting force components and selected 3D surface parameters. These models provide valuable insights into the relationships between the cutting parameters and the output variables, facilitating the optimization of the NiTi alloy milling process. The findings of this study contribute to a better understanding of the behavior of NiTi alloy during the milling process and offer information for process optimization. By employing a Box–Behnken experimental design, it was possible to investigate the effects of different parameter combinations on the components of total cutting force and selected 3D surface parameters according to ISO 25178, thus aiding in the identification of optimal milling conditions to achieve desired outcomes in the machining of NiTi alloy.

The paper presents a procedure for the determination of uncertainties in the modeling of surface roughness in the turning of NiTi alloys. The presented procedure is applicable both to the analysis of the measurement values of the two main roughness factors, as well as to research related to the prediction and optimization of the machining process. Type A and B, total, and expanded uncertainties were considered herein, and the obtained uncertainty values were assessed. A procedure for optimizing machining by applying the Monte Carlo (MC) method is also presented. The solutions presented in this paper are important from the point of view of practical solutions related to the prediction and optimization of the machining process. The considered procedure for determining and assessing uncertainty can be useful for the optimal selection of both machining parameters and measuring tools.

The paper presents an attempt to analyze comparative machinability of two different varieties of nitinol alloy type, or compare the susceptibility of these materials to change the volume, shape and dimension of adopted machining conditions. The machinability of the material can not be fully determined numerically by only one independent factor. Therefore multivariate analysis technique of weighted diagram radar was developed by authors. This technique allowed for the comprehensive identification machinability analyzed varieties of nitinol alloy exclusively on the basis of the specified in literature directional material properties and general recommendations tool manufacturers on the cutting conditions. In the paper the full usefulness of this technique to demonstrate the differences in machinability of different varieties of the same species alloy, without the need for lengthy and cost-intensive experimental trials was presented.

The machining of shape memory alloys, such as NiTi, presents challenges due to their specific physical, chemical, and mechanical properties. This study investigated the effect of the helix angle of milling tools—both uncoated and coated—on the cutting forces and the surface roughness of the milling process for a NiTi alloy. Experiments were conducted using the tools with and without coatings at various helix angles (20°, 30°, and 40°) and under different machining conditions. Optimization of the process was employed the Taguchi method to identify the best combination of the corresponding parameters. The results of the cutting force and the surface roughness measurements were analyzed and discussed in the context of optimizing the cutting conditions to achieve the desired outcomes. The results show that the lowest surface roughness values (Sa = 0.301 μm and Sz = 3.41 μm) were achieved with the coated tool at a helix angle of 30°, a feed per tooth of 0.02 mm, and a cutting speed of 45 m/min, while the lowest cutting force (F = 143.6 N) was observed with the coated tool at a cutting speed of 55 m/min, helix angle of 40°, and feed per tooth of 0.02 mm. This research provides valuable insights for industrial applications requiring the precise machining of NiTi in terms of the cutting forces and the surface quality. The findings reveal that the presence of the coating, along with an increase in the helix angle, significantly reduces the cutting forces, positively influencing the quality of the machined surface.