# Application of 3D Imaging for Analyzing the Chip Groove Shapes of Cutting Inserts
## 2 Materials and Methods  
Three-dimensional imaging of the rake face of the inserts was carried out using a VHX 7000 (Keyence Corporation, Osaka, Japan) measuring microscope with dedicated Keyence software (Analizator VHX-7000_970F, version 1.4.17.3). The measurements were carried out at a constant magnification, i.e., \(300\times\). The option of combining multiple images (\(7\times 7\) image composition) was used with a constant recording of 150 images in the Z-axis. The adopted method allowed for the recording of the measurement data in the form of a matrix with dimensions of about 8268 rows by 10,668 columns. The conversion of data to the XYZ system was carried out using the Kriging algorithm. The range of minimum and maximum heights (upper limit-lower limit) was set manually for each measurement. The basic technical data of the measuring microscope are presented in Table 1. To analyze the measurement results, software dedicated to the microscope and Surfer software (Surfer 2024, version 26.3.269) from Golden Software were used. Figure 1 presents the methodology of the measurements. Some of the calculations and data transformations, e.g., conversion of data in the form of a matrix to the XYZ system, were performed in Origin (OriginPro 2024, version 10.1.0.178) and MS Excel (Microsoft@Excel@for Microsoft 365 MSO, version 2402). Two types of inserts manufactured by Sandvik Coromant were used in the research, which differed in terms of the shape of the chip breaker on the rake face. Two types of chip breaker were analyzed: SF and SGF. The inserts had the manufacturer's marking: CNGG120404 (grade 1115) and CNMG120404 (grade H13A). Two cases of setting the cutting insert in relation to the surface of the workpiece were analyzed; that is, for the range of angle values \(K=60^{\circ}\) and \(K=90^{\circ}\). This range covers the clamping range of inserts in tool holders recommended by the tool manufacturer. The inserts and the shape of the chip formers are shown in Table 2. \begin{table}
\begin{tabular}{c c c} \hline \hline  & **Parameter** & **Description** \\ \hline \multirow{4}{*}{Camera} & & \(1/1.7\)-inch, \(12.22\)-megapixel \\  & Camera & CMOS image sensor; total \\  & & pixels: \(4168\) (H) \(\times\) \(3062\) (V) \\ \cline{1-1}  & The resolution of the XY stage & \(1\)\(\mu\)m \\ \cline{1-1}  & The \(Z\)-axis of the lens & \(0.1\)\(\mu\)m \\ \cline{1-1}  & Scanning system & Progressive \\ \cline{1-1}  & High dynamic range & \(16\)-bit intensity range through \\ \cline{1-1}  & & RGB data from each pixel \\ \cline{1-1}  & Keyence VHX 7000 & Built-in light source & High-intensity LED \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Technical data of the 3D microscope VHX 7000 Keyence. Inserts are recommended for machining difficult-to-cut materials, such as nickel and titanium alloys. Both tested inserts featured a reinforced cutting edge to protect against notch wear and a reinforced corner radius. The positive rake angle reduces cutting forces, which extends tool life. During the tests, the analysis was carried out, and the shape profiles of the chip former were determined for three values of depth of cut \(a_{p}\) and two values of major cutting-edge angle \(K\). The values of the variables are summarized in Table 3.  
In addition, vector map analysis was performed to determine the size and slope of the chip-breaker surface slopes. The theoretical surface area and contact length of the formed chip with the cutting tool material were also analyzed. In order to verify the results obtained from the theoretical analysis and with the use of 3D imaging, experimental studies were conducted. A plan of experimental research according to the Taguchi method was adopted. The variables were the depth of cut \(a_{p}\), feed \(f\), major cutting-edge angle \(K\), and the type of chip former. The eight research systems were determined. Table 4 presents the test plan and the assumed real values for individual  
Figure 1: Diagram of the measurement methodology.