Influence of the Nose Radius on the Machining Forces Induced during AISI-4140 Hard Turning: A CAD-Based and 3D FEM Approach

Abstract

The present study investigated the performance of three ceramic inserts in terms of the micro-geometry (nose radius and cutting edge type) with the aid of a 3D finite element (FE) model. A set of nine simulation runs was performed according to three levels of cutting speed and feed rate with respect to a predefined depth of cut and tool nose radius. The yielded results were compared to the experimental values that were acquired at identical cutting conditions as the simulated ones for verification purposes. Consequently, two more sets of nine simulations each were carried out so that a total of 27 turning simulation runs would adduce. The two extra sets corresponded to the same cutting conditions, but to different cutting tools (with varied nose radius). Moreover, a prediction model was established based on statistical methodologies such as the response surface methodology (RSM) and the analysis of variance (ANOVA), further investigating the relationship between the critical parameters (cutting speed, feed rate, and nose radius) and their influence on the generated turning force components. The comparison between the experimental values of the cutting force components and the simulated ones demonstrated an increased correlation that exceeded 89%. Similarly, the values derived from the statistical model were in compliance with the equivalent FE model values due to the verified adequacy.

CAD-Based 3D-FE Modelling of AISI-D3 Turning with Ceramic Tooling

“…At the pre-processing stage, the workpiece was modelled as deformable and meshed with approximately 32,000 to 60,000 tetrahedral elements depending on the value of the feed. The minimum element size of the mesh was set to 25% of the feed [39,40]. Moreover, a 7:1 ratio between the largest and the smallest element size of the mesh was applied to the section of the workpiece (see Figure 2b), so that the solid elements of the workpiece that participate in the removal process are created seven times smaller compared to the rest of the elements.…”

CAD-Based Automated Design of FEA-Ready Cutting Tools

“…Figure 2 depicts a standardized 80 • rhombic insert with its micro-geometry which comprises the cutting edge type, the chamfer angle and the chamfer width. In addition to the corner radius, the aforementioned parameters are crucial because they greatly affect the cutting forces during machining [20][21][22][23]. Moreover, according to Denkena et al [24] the cutting edge micro-geometry affects the tool life significantly due to changes in the characteristic tool wear behavior.…”

“…Specifically, Figure 5a depicts the initial step of the design process. At first, the front plane of the part document is selected because it is important to define a coordinate system that will serve through the FE analysis [22]. Hence, the Z-axis must be parallel to the tangential force vector, the Y-axis must be parallel to the radial force vector and finally, the X-axis must be parallel to the feed force vector.…”

Modeling of Cutting Force in the Turning of AISI 4340 Using Gaussian Process Regression Algorithm

“…The findings showed that cutting depth has a strong effect on the cutting force, the removal capability, and the material removal rate (MRR). The association between the essential parameters (nose radius, feed rate, and cutting speed) and their effect on the turning force components was investigated by Tzotzis et al [12]. The distinction between the resultant values of the cutting force factors and the simulations revealed an improvement in the association of over 89%.…”