This study focused on the optimization of Al—Mg to CuZn34 friction stir lap welding (FSLW) process for optimal combination of rotational and traverse speeds in order to yield favorable fracture load using Grey relational analysis (GRA). First, the degree of freedom was calculated for the system. Then, the experiments based on the target values and number of considered levels, corresponding orth...

A subtrochanteric femur fracture after cannulated screw fixation of a femoral neck fracture is a devastating complication. We hypothesized that an apex-distal screw orientation would tolerate higher loads to subtrochanteric fracture. Human cadaveric femora were instrumented with three cannulated screws in either an apex-distal or an apex-proximal configuration. Specimens were loaded along the m...

the work presented in this paper investigates the causes of size effects in structural-concrete members. it isbased on the use of a finite-element model found to yield realistic predictions of structural-concrete behavior in allcases investigated to date. in fact, the previous use of this model in investigations of size effects in reinforced-concretebeams indicated that such effects reflect the...

Fracture mechanics is a field of solid mechanics interested with the behaviour of materials under certain loads their distribution and finally the fracture criteria of given materials.This Paper evaluates size dependency of fracture parameters, fracture energy (Gf) and fracture process zone effective length (Cf) of concrete concluded as per Bazant’s size effect method. Fracture mechanics standa...

PURPOSE The purpose of part II of this in vitro study was to compare the fracture load of two-piece zirconia custom abutments with different thicknesses and angulations. MATERIALS AND METHODS Forty zirconia custom abutments were divided into four groups as follows: group A1: 0.7 mm thickness and 0° angulations; group A2: 0.7 mm thickness and 15° angulations; group B1: 1 mm thickness and 0° an...

BACKGROUND Despite that a mid-third simple transverse femoral shaft fracture has been traditionally treated with an unlocked reamed intramedullary nail, recently a static locked reamed intramedullary nail has been favored by some orthopedists to avoid missing extended fracture lines. A prospective comparison of both nails was conducted to investigate the superiority between the nails from biome...

The off-loading characteristics of the cast-braces of 30 patients with fractures of the shaft of the femur have been investigated, during axial loading, using strain-gauge transducers. These were applied at the level of the fracture, where the cast was circumferentially split, and to the hinges of the brace at the knee. They measured the load transferred between the two portions of the thigh ca...

This paper presents two main results. The first result indicates that in materials with broadly distributed microscopic heterogeneities, the fracture strength distribution corresponding to the peak load of the material response does not follow the commonly used Weibull and (modified) Gumbel distributions. Instead, a lognormal distribution describes more adequately the fracture strengths corresp...

To evaluate the influence of cementation on fracture load of anterior crowns made of CAD/CAM-resin-blocks (ART), leucite-reinforced glass-ceramics (LRG), lithium disilicate ceramics (LIT), veneered zirconia (ZRO) and veneered alloy (DEG). Each crown group (n=15/subgroup) was cemented on the metal abutment as follows: i. using glass ionomer, ii. using self-adhesive resin cement, and iii. not cem...

The study describes the acoustic emission (AE) activity during human femur tissue fracture. The specimens were fractured in a bending-torsion loading pattern with concurrent monitoring by two AE sensors. The number of recorded signals correlates well with the applied load providing the onset of micro-fracture at approximately one sixth of the maximum load. Furthermore, waveform frequency conten...