OBJECTIVE To compare the deflection load characteristics of homogeneous and heterogeneous joints made by laser welding using various types of orthodontic wires. MATERIALS AND METHODS Four kinds of straight orthodontic rectangular wires (0.017 inch × 0.025 inch) were used: stainless-steel (SS), cobalt-chromium-nickel (Co-Cr-Ni), beta-titanium alloy (β-Ti), and nickel-titanium (Ni-Ti). Homogene...

The objective of this study was to investigate the effects of cryo-treatment on the microstructure, corrosion behavior, and mechanical properties of Ti before and after laser welding. The microstructure was studied by optical microscopy. It was found that the grain size for Ti became smaller after cryo-treatment. Cryo-treatment could also refine and stabilize the crystal lattice structure and d...

A copper/Q235 steel/copper composite block with excellent bonding interfaces was prepared by explosive welding which a promising technique to fabricate laminates. The microstructure and mechanical properties of the were investigated via tensile-shear test, optical microscope (OM), X-ray diffraction (XRD), scanning electron (SEM), back-scattered (EBSD). results showed that shear strength upper-i...

a novel mathematical model has been developed to aid the formulation of emulsion explosives. this mathematical model calculated heat of explosion, oxygen balance and raw material cost as a function of explosive ingredients, and the solution of the mathematical model was obtained by a ms excel program. the effects of the different content of nh4no3, nano3, h2o, and span-80 and composite fuel oil...

We define an invariant of welded virtual knots from each finite crossed module by considering crossed module invariants of ribbon knotted surfaces which are naturally associated with them. We elucidate that the invariants obtained are non-trivial by calculating explicit examples. We define welded virtual graphs and consider invariants of them defined in a similar way. 2000 Mathematics Subject C...

Nowadays, the role of light weight materials has grown up in important industries such as aerospace and biomechanics, but before the appliance, their strength should be increased. A modern way to increase this factor along with the lightweight factoris using bimetal sheets, hence, the design of multilayer sheets has been very much considered recently. In this study, explosive welded Cu/St/Cu mu...

There are a wide range of important applications for metal tube materials in various fields. The production process of high-frequency longitudinally welded pipe includes first using a roller to coil the long steel strips of a certain size into a cylinder shape, and then join them by heating the steel materials at the welding edge with a high-frequency welding machine — Fig. 1. The processes inc...

This paper refers to some simulation tests concerning the formability and springback of a U-shaped part manufactured from tailor welded stripes. The final geometry of the obtained part is seriously affected by springback phenomenon. This paper work is trying to prove out the important role samples dimension has on the springback phenomenon. The influence of the samples width on the tailor welde...

Two welded (respectively virtual) link diagrams are homotopic if one may be transformed into the other by a sequence of extended Reidemeister moves, classical Reidemeister moves, and self crossing changes. In this paper, we extend Milnor’s μ and μ̄ invariants to welded and virtual links. We conclude this paper with several examples, and compute the μ invariants using the Magnus expansion and Pol...

Two welded (respectively virtual) link diagrams are homotopic if one may be transformed into the other by a sequence of extended Reidemeister moves, classical Reidemeister moves, and self crossing changes. In this paper, we extend Milnor’s μ and μ̄ invariants to welded and virtual links. We conclude this paper with several examples, and compute the μ invariants using the Magnus expansion and Pol...