Temperature Rise and Welding Characteristics of Various-Frequency Ultrasonic Plastic Welding Systems

Abstract

Welding characteristics and temperature increases of ultrasonic plastic welding parts over a frequency range from 27 to 94 kHz are studied. Using 27, 40, 67, and 94 kHz ultrasonic plastic welding systems, temperature increases at welding surfaces of lapped 1.0-, 2.0-, and 3.0-mm-thick polypropylene plates and polymethyl methacrylate plates are measured using 0.1-and 0.2-mm-diameter thermocouples inserted between plates, and temperature distributions at cross sections of lapped plate specimens are measured using a thermotracer. The 94 kHz vibration system used for ultrasonic plastic welding consists of a bolt-clamped Langevin-type longitudinal vibration source using four 30-mm-diameter piezoelectric ceramic (PZT) rings, a stepped horn (vibration velocity transform ratio N ¼ 3:0) and a catenoidal horn (N ¼ 3:13) with an 8-mm-diameter welding tip. The other vibration systems have similar configurations. In the case of using a higher-frequency system, increases in temperature measured at the welding parts are larger. Temperature rises are larger for lapped plate specimens than that for a one-piece specimen owing to the vibration loss of welding surfaces.

Microstructure and Mechanical Properties of Ultrasonic Welded Joint of 1060 Aluminum Alloy and T2 Pure Copper

“…D. Bakavos et al [4] measured the temperature rise of an ultrasonic spot bonding of aluminum, and pointed out that the temperature rose extremely quickly and the temperature was affected by the ultrasonic energy. In addition, in order to get a perfect joint, the ultrasonic energy (or welding duration) should not be too high, because that the temperature rise may induce a strength loss of the metals [24]. …”

Temperature development of cardboard in contact with high-frequency vibrating metal surfaces

“…It was found that the entire cross section was heated uniformly, and hysteretic losses were suspected to be the cause. However, investigations by Hongoh et al (2006) showed that friction at the interfaces has a major influence. Plates of polypropylene (PP) and respectively polymethylmethacrylate (PMMA) having a thickness of 3 mm and three polished plates of 1-mm thickness being clamped together were subjected to the same ultrasonic vibrations.…”

Reliability of Fine-Pitch Flip-Chip (COG) Bonding with Non-Conductive Film Using Ultrasonic Energy

“…Recently, ultrasonic FCB (UFCB) technology has attracted research attention owing to several advantages such as fast bonding time, low bonding temperature, low bonding pressure, low environmental impact, high electrical performance, and good reliability [4,5]. However, the joint strength of UFCB is no higher than that using adhesive bonding with methods such as NCA and ACA.…”