Room temperature monotonic and cyclic stress–strain curves for single crystal and polycrystalline NiTi shape memory alloys containing Ti3Ni4 precipitates are presented. The tensile and compressive single crystal results illustrate the importance of crystallographic texture, the unidirectional nature of the martensitic transformation, and martensite detwinning on tension-compression stress–strai...

Differences in mechanical properties between endodontic instruments might be related to the chemical composition, phase constitution, or fabrication process of nickel–titanium (NiTi) endodontic instruments. An awareness and knowledge of the mechanical properties of NiTi endodontic files and their association with the metallurgical properties is useful for clinicians to understand the behavior o...

Porous NiTi alloys were prepared by microwave sintering using ammonium hydrogen carbonate (NH4HCO3) as the space holder agent to adjust the porosity in the range of 22-62%. The effects of porosities on the microstructure, hardness, compressive strength, bending strength, elastic modulus, phase transformation temperature and superelasticity of the porous NiTi alloys were investigated. The result...

INTRODUCTION The aim of this study was to assess the extent of adoption, application and the associated issues with the nickel-titanium (NiTi) rotary instruments and techniques amongst endodontists and general dentists in Tehran. MATERIALS AND METHODS A total of 33 questions classified in six categories of demographics, frequency rate of NiTi rotary instrumentation and information. The sample...

INTRODUCTION The performance and mechanical properties of nickel-titanium (NiTi) instruments are influenced by factors such as cross-section, flute design, raw material, and manufacturing processes. Many improvements have been proposed by manufacturers during the past decade to provide clinicians with safer and more efficient instruments. METHODS The mechanical performance of NiTi alloys is s...

NiTi alloy has been used as the raw material for making endodontic files. The interest in NiTi instrument research has not waned with time. In fact, there is a renewed interest in this field, notably through the application of modern research tools and techniques from other fields, making it a truly cross-disciplinary area of research. In 1988, Walia and colleagues introduced nickeltitanium (Ni...

NiTi alloy has been used as the raw material for making endodontic files. The interest in NiTi instrument research has not waned with time. In fact, there is a renewed interest in this field, notably through the application of modern research tools and techniques from other fields, making it a truly cross-disciplinary area of research. In 1988, Walia and colleagues introduced nickeltitanium (Ni...

Five types of porous Nickel-Titanium (NiTi) alloy samples of different porosities and pore sizes were fabricated. According to compressive and fracture strengths, three groups of porous NiTi alloy samples underwent further cytocompatibility experiments. Porous NiTi alloys exhibited a lower Young's modulus (2.0 GPa ~ 0.8 GPa). Both compressive strength (108.8 MPa ~ 56.2 MPa) and fracture strengt...

Coated archwires and ceramic brackets have been developed to improve facial esthetics during orthodontic treatment. However, their mechanical behavior has been shown to be different from metallic archwires and brackets. Therefore, the aim of this study was to compare the deflection forces in coated nickel-titanium (NiTi) and esthetic archwires combined with ceramic brackets. Material and Method...

NiTi powders are densified in the presence of argon gas, whose initial pressure is varied between 1 and 33 atm, to create NiTi billets containing isolated Ar-filled pores. Upon vacuum annealing, the pressurized pores expand by creep of the surrounding NiTi matrix at rates which are in agreement with a simple analytical model up to 16% porosity. Beyond this porosity, foaming becomes very slow, a...