BACKGROUND Titanium-molybdenum alloy (TMA) and stainless steel (SS) wires are commonly used in orthodontics as arch-wires for tooth movement. However, plastic deformation phenomenon in these arch-wires seems to be a major concern among orthodontists. This study aimed to compare the mechanical properties of TMA and SS wires with different dimensions. MATERIAL AND METHODS Seventy-two wire sampl...

Here, • m > 0 is the mass. • k > 0 is the spring constant and the spring force −ku(t) is modeled to be proportional to u(t) (i.e. Hooke’s law). The minus sign shows that it is always a restoring force which pulls the mass back towards the equilibrium. • γ ≥ 0 is the damping constant. The damping force may come from the medium (e.g. air, water, or honey), the spring or other sources. It has a mi...

Thermo-mechanical densification of sawn timber results in improved mechanical properties, but densified wood remains a fairly expensive niche product, partially because high-cost batch processing. Densification continuous process could address this problem and was shown to be possible previous research. The outcomes were limited proofs-of-concept, due insufficient cooling capabilities the used ...

But this is not real life! Suppose next that we are still moving in a straight line but the force is variable: indeed, the typical example of this is that of a spring: suppose we have a mass M on a spring, and we stretch the mass a distance of x units from its equilibrium position. The spring will pull back in the opposite direction, and the early British scientist Robert Hooke formulated a sim...

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...

Bending operations are frequently used to produce sheet metal components. Spring-back is an issue in sheet metal forming processes and some times is a principle problem for producing precise components. This is more important if some kind of cuttings exists on the bending surfaces. Experiments show that punched holes on bending surfaces affect the value of the spring-back. In this paper the spr...