Limiting dome height (LDH) tests were used to evaluate the formability of laser butt welded blanks of the dual phase 980 steel in comparison with the base metal. Two different lasers were used: diode and Nd:YAG, giving a wide range of welding thermal cycles. A sharp decrease in LDH was observed in the welded specimens due to the formation of a softened zone in the outer heat affected zone. Soft...

In this study, the effect of repair on fatigue life of tubular joints is investigated. Six cracked specimens precedently subjected to fatigue loading undergone to weld repair. Two of those specimens were shot peened before primary fatigue loading.  It is shown that repair gives rise to about 150% increase in fatigue life for original specimens while the increase of fatigue life for shot-peened ...

The performance of laser welding of Ti and two dental precious alloys (Ag-Pd-Au, Au-Pt-Ag) was investigated by mechanical testing and microscopic observation, using butt joint as design. The laser irradiation was done using a commercial Nd:YAG dental laser-welding device in a single pulse mode with output currents 150, 200, 250, 300A, spot diameters 0.6, 0.9, 1.2mm, and pulse duration 10ms. The...

STATEMENT OF PROBLEM The fracture of complete denture is a common occurrence in the field of prosthodontics. Often if all other criteria are met such as good aesthetics, occlusion, and functionality; denture repair is acceptable. Once denture fractures, we would want the joint surface strength to be as good as original. PURPOSE The purpose of this study was to determine the effect of differen...

The present study presents the influence of welding current, welding voltage, welding speed and external magnetic field on hardness of shielded metal arc welded mild steel joints. Mild steel plates of 6 mm thickness were used as the base material for preparing single pass butt welded joints. Speed of welding was provided by cross slide of a lathe machine, external magnetic field was obtained by...

A smart, bi-directional model has been developed to determine three-dimensional temperature profiles, weld geometry and the transformed phase fraction during gas tungsten arc (GTA) butt welding. The model is capable of estimating input parameters such as the net input power, welding speed, effective thermal conductivity, and, activation energy, preexponential factor and exponent in JohnsonMehl-...

Fatigue crack growth observed in tubular K-joint specimens, typical of tubular bridge structures, always initiates at the chord crown toe locations whether the applied stress range is tensile or compressive. Even though other locations around the weld have highest hot-spot stresses, chord crown toe locations are still the most critical. This raises the question about the relevant tensile residu...