Ball burnishing is a superfinishing operation whose objective is the enhancement of surface integrity of previously machined surfaces, hence its appropriateness to complement chip removal processes at the end of a production line. As a complex process involving plastic deformation, friction and three-dimensional interaction between solids, numerical solutions and finite element models have typically included a considerable amount of simplifications that represent the process partially. The aim of this paper is to develop a 3D numerical finite element model of the ball burnishing process including in the target workpiece real surface integrity descriptors resulting from a ball-end milled AISI 1038 surface. Specifically, its periodical topological features are used to generate the surface geometry and the residual stress tensor measured on a real workpiece is embedded in the target surface. Secondly, different models varying the effect of the coefficient of friction and the direction of application of burnishing passes with regards to the original milling direction are calculated. Results show that the resulting topology and residual stresses are independent of the burnishing direction. However, it is evident that the model outputs are highly influenced by the value of the coefficient of friction. A value of 0.15 should be implemented in order to obtain representative results through finite element models.

Although numerous references present the beneficial effects on surface integrity of ultrasonic vibration-assisted ball burnishing (UVABB), nothing has been reported about the dynamic behavior of the UVABB tool, workpiece, and machine triad during the process. In this paper, a dynamic monitorization through a set of 5 accelerometers is tested to analyze the interactions between the tool–workpiece–machine mechanical assembly. A UVABB tool attached to a milling machine and equipped with a piezoelectric stack that is able to assist the process with a 40-kHz vibration is tested on a milled C45 steel surface. First, the natural frequencies of the mechanical system are obtained through hammer impact tests. Then, the vibratory signals transmitted during the execution of the process are monitored and compared to those: two feed velocities and two burnishing preloads, all with and without vibration-assistance. Results show that the proposed accelerometer set is valid to assess the behavior of a UVABB process. The system’s natural frequencies are not varied by vibration-assistance and are not excited when the piezoelectric is functioning. It is confirmed that UVABB is safe for the machine and the tool, and there is no unexpected excited frequencies due to the piezoelectric excitation.

This paper focuses on a resonant system used to induce a low-amplitude movement and ultrasonic frequency to complement a ball burnishing process on a lathe. The system was characterized through the combination of different techniques. A full vibratory characterization of this process was undertaken with the purpose of demonstrating that the mechanical system—composed of the tool and the machine—does not present resonance phenomena during the execution of the operation that could lead to eventual failure. This dynamic analysis validates the adequateness of the tool when attached to an NC lathe, which is important to guarantee its future implementation in actual manufacturing contexts. A further aim was to confirm that the system succeeds in transmitting an oscillating signal throughout the material lattice. To this end, different static and dynamic techniques that measure different vibration ranges—including impact tests, acoustic emission measurement, and vibration measurement—were combined. An operational deflection shape model was also constructed. Results demonstrate that the only high frequency appearing in the process originated in the tool. The process was not affected by the presence of vibration assistance, nor by the burnishing preload or feed levels. Furthermore, the frequency of the assisting ultrasonic vibration was characterized and no signal due to possible damage in the material of the specimens was detected. These results demonstrate the suitability of the new tool in the vibration-assisted ball burnishing process.

In this paper, a resonant system that produces a movement of low amplitude and ultrasonic frequency is used to achieve the vibration assistance in a ball-burnishing process. A full vibration characterization of this process performed in a lathe was done. It is carried out by a new tool designed in the research group of the authors. Its purpose is to demonstrate that the machine and the tool do not have any resonance problem during the process and to prevent possible failures. The analysis of this dynamic behaviour permits to validate the suitability of the tool when it is anchored to a numerical control lathe. This is very important for its future industrial implementation. It is also intended to confirm that the system adequately transmits vibrations through the material. To do this, a methodology to validate the dynamic tool behaviour was developed. Several techniques that combine the usual and ultrasonic vibration ranges through static and dynamic measurements were merged: vibration and acoustic emission measurements. An operational deflection shape (ODS) exercise has been also performed. Results show the suitability of the tool used to transmit the assistance vibrations, and that no damage is produced in the material in any case.