From the images of HR-TEM, FE-SEM, and AFM, the cold welding of gold nanoparticles (AuNPs) on a mica substrate is observed. The cold-welded gold nanoparticles of 25 nm diameters are found on the mica substrate in AFM measurement whereas the size of cold welding is limited to 10 nm for nanowires and 2~3 nm for nanofilms. Contrary to the nanowires requiring pressure, the AuNPs are able to rotate ...

In this study, the effect of temperature on the diffusion welding of AZ31 magnesium alloy and 7075 aluminum was discussed. Diffusion welding temperature was the most important parameter since all mechanisms are sensitive to temperature in Diffusion welding method. Intrusive contacts between the two alloys at temperatures of 430, and 440 °C 450 and took 60 min. In all tests constant pressure and...

in this study, the effects of linear and rotational speed of the friction stir welding tool was investigated on the heat generation and distribution at surface and inside of workpiece, material flow and geometry of the welding area of poly methyl methacrylate (pmma) workpiece. the commercial cfd fluent 6.4 software was used to simulation of the process with computational fluid dynamic technique...

0261-3069/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.matdes.2009.05.023 * Corresponding author. Tel.: +1 615 3223322. E-mail address: [email protected] (D.H. A friction stir welding (FSW) tool geometry, consisting of a shoulderless conical probe, is investigated for application to closed contour welding, variable thickness welding, and open-loop control welding. By use of a t...

The homopolar pulse welding process uses a single unidirectional, high current electrical pulse from a homopolar generator to heat the interface between two workpieces in solid contact. When the interface reaches an optimum temperature, forging pressure is applied, and the workpieces coalesce without melting and without use of either a flux or a filler. The weld is completed in from 1 to 2 s. B...

Submerged arc welding is preferred over other methods of welding because of its inherent qualities like easy control of process variables, high quality, deep penetration, smooth finish, capability to weld thicker sections. Since the development of submerged arc welding process, welding engineers are striving for reduction in welding cost without compromise in the performance of the weld. Flux u...

In this study, the effect of temperature on the diffusion welding of AZ31 magnesium alloy and 7075 aluminum was discussed. Diffusion welding temperature was the most important parameter since all mechanisms are sensitive to temperature in Diffusion welding method. Intrusive contacts between the two alloys at temperatures of 430, and 440 °C 450 and took 60 min. In all tests constant pressure and...

In the present study, method of ultrasonic welding of plastics is used to join the overlap of Polypropylene composites reinforced with glass fiber. The effects of process parameters, including time, pressure, vibration amplitude and amount of glass in composite on strength of welds. To reduce the number of tests and cost, the effect of changing parameters on strength was examined through Box-Be...