The wide-gap aluminothermic rail welds with root opening of 50-70 mm were produced using plain carbon steel rail and non-alloy aluminothermic charge. Mechanical properties and micro-structure of the weld metal and HAZ as well as the impact energy and the fracture toughness of the welds were investigated. The yield and tensile strength of wide-gap welds were about 98% and 95% of the base metal, ...

Various types of hydroxyapatite (HA) structures have received great attention of scientific researcher in biomaterials field. Also, it is common that HA is the essential inorganic materials in human hard tissue such as bone or teeth. Fracture toughness and micro-hardness properties are the important parameters required for the prediction of the mechanical performance of biomaterials structures ...

BACKGROUND This study compared two well-known computer-aided-design/computer-aided-manufactured (CAD/CAM) blocks (Paradigm MZ100 [3M ESPE] and Vitablocs Mark II [Vita] in terms of fracture toughness (Kic), index of brittleness (BI) and stress/strain distributions. MATERIAL AND METHODS Three-point bending test was used to calculate the fracture toughness, and the relationship between the Kic a...

magnesium alloys in liquid-phase condition form surface oxide films due to their high rate of oxidation. oxide films enter the melt as a result of surface turbulence, and remain inside the workpiece after solidification. the incoherent nature of their interface causes decreases in mechanical properties and reliability of castings. the effect of critical velocity and greater velocities of enteri...

Recent studies document linear elastic response of muddy marine sediments to load and deformation on temporal and spatial scales relevant to animal movement, with burrowers making openings for movement in such sediments by fracture. Cracks propagate through linear elastic solids in mode I (opening-mode crack growth) when the stress intensity factor (KI) at the crack tip exceeds the material’s f...