Deep cold rolling with ultrasonic vibrations-a new mechanical surface enhancement technique

The paper presents a newly developed mechanical surface enhancement technique utilising ultrasonic vibrations, namely Ultrasonic Deep Cold Rolling (UDCR) process. UDCR differs from Conventional Deep Cold Rolling (CDCR) by applying static and also dynamic forces resulting from ultrasonic vibrations. The principle and concept of the new process are described. The evaluation and comparison of experimental results (e.g. surface roughness, surface micro-hardness and compressive residual stresses) obtained after treatments of Ti-6Al-4V specimens are discussed. The advantages of proposed technique and its potential applications are also reported. UDCR could be used for treating thin components without deteriorating the component shape as less pressure is being applied on the part surface during UDCR. Compressive residual stresses of about 900 MPa at 0.2 mm depth from the surface can be achieved.