Lamellar thermal actuators, for temperature control in hydraulic systems, were manufactured from a Cu-Zn-Al shape memory alloy and trained in bending, between 100 and 500 cycles. The cycles were performed automatically and comprised electrical heating and ventilated air cooling during which a load, fastened at actuator’s free end, was lifted by shape memory effect and lowered by martensite-formation softening, respectively. The structural effects

The surface micro-reliefs of primary martensite plates, representative for two shape memory alloys (SMAs) with different crystalline structures were compared from qualitative and quantitative point of view by scanning electron microscopy and atomic force microscopy, respectively. Qualitative evaluations revealed larger widths and heights of the primary plates of e hexagonal close packed (hcp) martensite, in an Fe-Mn-Si-Cr-Ni SMA than those of b29

A normalized hot forged Cu-15Zn-6Al (mass. %) shape memory alloy (SMA) was subjected to tempering heat treatments meant to enhance the reversion to parent phase (austenite) of thermally induced martensite. By means of differential scanning calorimetry (DSC) the reversibility of martensitic transformation was verified during constant-rate heating-cooling cycles. The results have showed that 373 K- tempering destabilized martensite and enabled its

Temperature memory effect (TME) is usually manifested by a kinetic stop during reverse transformation of thermally induced martensite to parent phase, after performing an incomplete heating in the previous thermal cycle, applied to a shape memory alloy (SMA). Technically TME causes the splitting of the endothermic peak corresponding to martensite reversion, on differential scanning calorimetry (DSC) thermograms. The present paper illustrates new

A major part of the computational effort in chemical process simulation and compositional reservoir simulation is spent by phase equilibrium calculations: phase split and phase stability analysis. The calculation algorithms must be efficient and highly robust. The reduction methods offer an attractive alternative to conventional methods. Several recent papers have questioned on the efficiency of the reduction methods as compared to conventional methods,

In this work, a new method is proposed for solving Underwood's equations. Newton methods cannot be used without interval control, and may require many iterations or experience severe convergence problems if the roots are near poles and the initial guess is poor. It is shown that removing only one adjacent asymptote leads to convex functions, while removing both asymptotes leads to quasi convex functions which are close to linearity on wide intervals.