Effect of temperature and flux concentration on soldering of base metal

Abstract

The present study used the acoustic ing device. The results were analysed by ANOVA and Tukey LSD test. UTS at different temperatures emission (AE) technique to evaluate interactions among soldering temperature, flux treatment, and showed no significant difference according to either mechanical or acoustic results. But in the 1200°C the resultant ultimate tensile strength (UTS). Scangroup, the UTSs and AE counts showed significant ning electron microscopy (SEM) was used to examine fracture surfaces of the solder joints. Specimens differences (PB 0·05) at both flux concentrations. SEM showed that the 1200C group had better denwere cast from removable partial denture alloy and then placed in a jig with a gap distance of 1·0 mm. dritic crystal structure than did the 1150°C group. A high-frequency soldering machine with an optiIn the 1200°C group specimens with 67% flux had fewer flux inclusion bodies and dendritic crystals cal pyrometer was used for soldering at 1150°C and 1200°C, respectively. The flux concentrations were than did specimens with 75% flux. The 75% flux subgroup produced high-amplitude (60-70 dB) 67% and 75%. The soldered specimens were subacoustic signals within the elastic deformation jected to tensile test at a crosshead speed of zone, while the 67% flux subgroup produced similar 0·05 mm/min. During testing, acoustic emissions in signals within the plastic deformation zone, either the frequency range of 100-1200 kHz were colbeyond the 0·2% yield point or before fracture. lected, filtered, recorded, and processed by a sens-

Fracture of fiber-reinforced composites analyzed <i>via</i> acoustic emission

“…During crack propagation, most NRC specimens had limited AE activity -indicating that few events occurred within the specimens at fracture 36) . NRC specimens were composed of composite material only with no fiber addition, hence fewer microcracks were expected to occur.…”

Effect of gap distance on tensile strength of preceramic base metal solder joints

“…19 Porosity in solder joints may be produced by flux entrapment due to over-fluxing and under-heating, in addition to wetting ability of molten solder in solder gap space ( Figure 3 ). 1 , 3 , 18 …”

“…Procedures such as long-span fixed partial dentures, repair of clasps and frameworks, addition of wrought wire clasps in removable prostheses, and the superstructures of dental implants all need soldering to improve accuracy and solve fitting problems. 1 Two main methods are available for soldering: 2 preceramic and postceramic soldering, which are done before and after porcelain application, respectively. Preceramic soldering is often performed at a temperature very close to the melting point of parent metals, but postsolder melts below the pyroplastic range of the porcelain, which is considerably lower than the melting point of the parent metal.…”

The Effect of Laser Welding on the Tensile Strength and Radiographic Analysis of Co-Cr Repaired Joints

“…During soldering, the parental metal surface should retain its non-oxidized status and absence of impurities in order to form a tight contact between the solder and the parental soldered surface. (23)…”