A review of shape memory alloy research, applications and opportunities

Aircraft wings are a compromise that allows the aircraft to fly at a range of flight conditions, but the performance at each condition is sub-optimal. The ability of a wing surface to change its geometry during flight has interested researchers and designers over the years as this reduces the design compromises required. Morphing is the short form for metamorphose; however, there is neither an exact definition nor an agreement between the researchers about the type or the extent of the geometrical changes necessary to qualify an aircraft for the title ‘shape morphing.’ Geometrical parameters that can be affected by morphing solutions can be categorized into: planform alteration (span, sweep, and chord), out-of-plane transformation (twist, dihedral/gull, and span-wise bending), and airfoil adjustment (camber and thickness). Changing the wing shape or geometry is not new. Historically, morphing solutions always led to penalties in terms of cost, complexity, or weight, although in certain circumstances, thes...

A Review of Morphing Aircraft

Shape morphing of aircraft wing: Status and challenges

Shape-Memory Materials

Constitutive model for the numerical analysis of phase transformation in polycrystalline shape memory alloys

Shape memory alloys : fundamentals, modeling and applications

Modelling and characterization of a porosity graded lattice structure for additively manufactured biomaterials

Development of a porous metallic femoral stem: Design, manufacturing, simulation and mechanical testing

http://www2.dec.fct.unl.pt/projectos/SMA_2008/Bib/TIMTL07.pdf

Built in dampers for family homes via SMA: An ANSYS computation scheme based on mesoscopic and microscopic experimental analyses

Background The current total hip prostheses with dense femoral stems are considerably stiffer than the host bones, which leads to such long-term complications as aseptic loosening, and eventually, the need for a revision. Consequently, the lifetime of the implantation does not match the lifetime expectation of young patients. Method A femoral stem design featuring a porous structure is proposed to lower its stiffness and allow bone tissue ingrowth. The porous structure is based on a diamond cubic lattice in which the pore size and the strut thickness are selected to meet the biomechanical requirements of the strength and the bone ingrowth. A porous stem and its fully dense counterpart are produced by laser powder-bed fusion using Ti-6Al-4V alloy. To evaluate the stiffness reduction, static testing based on the ISO standard 7206-4 is performed. The experimental results recorded by digital image correlation are analyzed and compared to the numerical model. Results & conclusions The numerical and experimental force-displacement characteristics of the porous stem show a 31% lower stiffness as compared to that of its dense counterpart. Moreover, the correlation analysis of the total displacement and equivalent strain fields allows the preliminary validation of the numerical model of the porous stem. Finally, the analysis of the surface-to-volume and the strength-to-stiffness ratios of diamond lattice structures allow the assessment of their potential as biomimetic constructs for load-bearing orthopaedic implants.

Patrick Terriault

Papers

Shape memory alloys : fundamentals, modeling and applications

Modelling and characterization of a porosity graded lattice structure for additively manufactured biomaterials

Development of a porous metallic femoral stem: Design, manufacturing, simulation and mechanical testing

Built in dampers for family homes via SMA: An ANSYS computation scheme based on mesoscopic and microscopic experimental analyses

Femoral stem incorporating a diamond cubic lattice structure: Design, manufacture and testing.