Scopul nostru este sprijinirea şi promovarea cercetării ştiinţifice şi facilitarea comunicării între cercetătorii români din întreaga lume.
Autori: M.Susan and L.G.Bujoreanu
Editorial: Centro nacional de Investigaciones Metalurgicas, Revista de Metalurgia de Madrid, 35(6), p.379-383, 1999.
The friction reversion mechanism during ultrasonic vibration drawing (UVD) of wires has been detailed for the case when the die is located at the oscillation maxima of the waves and actuated parallel to the friction force direction. The decrease of the drawing force for the UVD technology as compared to classical drawing has been explained by means of the intermittent contact in the metal-die forming area. A relationship has been derived fro the UVD friction coefficient μUS that allowed the analytical determination of the drawing force. In the case of the Romanian RUL IV (AISI 52100) ball bearing steel wires, good agreement has been found between the analytical and the experimental values of the drawing forces that have decreased, as compared to classical drawing, by more than 5 % for drawing rates lower than 0.66 m/s.
Cuvinte cheie: ultrasonic vibration drawing, friction reversion mechanism, friction coefficient, drawing force, intermittent contact