Cases of fractured mobile unicompartmental knee bearings have recently been reported. The purpose of this study was to understand the mechanics behind these fractures and to examine the influence of different design modifications. A parametric finite element model was used to examine the influence of different geometrical factors on the stresses within the bearing. Crack initiation occurred cli...

The focus of this study is to investigate the mechanical properties and fracture behaviour of polydimethylsiloxane filled crystalline silica composites (PDMSJCS) via tensile test. The PDMSICS composites were fabricated by using casting method and cured at room temperature for 24 hours. Crystalline silica were filled into PDMS at composition of 2, 6, 10 wt%. The tensile properties of PDMS/2wt%CS...

an epoxy resin was modified by silica nanoparticles and cured with an anhydride. the particles with different batches of 12, 20, and 40 nm sizes were each distributed into the epoxy resin ultrasonically. electron microscopy images showed that the silica particles were well dispersed throughout the resin. tensile test results showed that young’s modulus and tensile strength increased with the vo...

This study focuses on the optimizing the microstructure to improve the efficiency for healing interfacial debonding in fiber-reinforced polymers (FRPs). Healing is accomplished by incorporating a microcapsulated healing agent and catalytic chemical trigger within a coating layer on the surface of the fiber strands. Self-healing is demonstrated on flat tensile specimens of unidirectional FRPs. T...

The heat treatments have been designed to vary the matrix microstructure in P/M processed SiC reinforced 7xxx Aluminum alloys to determine the effects of matrix microstructure, interface behavior on the mechanical properties. Smooth tensile, notched bend tests were performed. The results conclude that the clustered regions have been observed as preferred initiation sites in both tensile and not...

Tensile stress-strain curves a r e obtained at s t rain rates of %lo-'+, ~ 1 0 and c1000/s for carbon, Kevlar and glass fibre woven-reinforced polyester resin compos i tes and the variation of modulus, tensile strength and fracture strain with strain rate is determined. A change in the failure mode at the highest strain rates is observed for the glass but not the carbon or Kevlar reinforced com...

This paper investigated the effects of combining fibers with self-consolidating concrete (SCC). 12 series of test specimens were prepared using three kinds of fibers including steel, polyphenylene sulfide (PPS) and glass fibers with four different volumes fractions and one specimen without fibers as a reference sample. All plans were subjected to fresh concrete tests. For mechanical behavior of...

assessment of the correlation between rock brittleness and rock fracture toughness has been the subject of extensive research works in the recent years. unfortunately, the brittleness measurement methods have not yet been standardized, and rock fracture toughness cannot be estimated satisfactorily by the proposed indices. in the present study, statistical analyses are performed on some data col...

The fracture and crack growth of mechanical structures is a usual phenomenon which is due to the application of tensile, cyclic loading or thermal stresses on the structure. So introducing of methods to prevent the crack growth is useful. Afterward, one of the repairing methods of crack growth, consisting to make a hole in the crack tip to elimi-nate the sharp corners, was explained. This metho...