In the present study, AZ41 and AZ51 alloys were fabricated using disintegrated melt deposition technique followed by hot extrusion. AZ41/Yttria and AZ51/Yttria composites were prepared using 0.6 wt% yttria nano particles in the alloys using the same fabrication technique. From the tensile test results, both strengths (yield and tensile) and ductility were improved in AZ51 when compared to AZ41....

Mixed-surface octyl/methoxyundecyl a-zirconium phosphonates (ZrPs) were investigated as distributed nanoscale fillers, in concentrations up to 50% w/w, for the purpose of increasing the elastic modulus and yield strength of polycaprolactone (PCL) without a meaningful reduction of its ductility. The volumetric nanoparticle loadings were estimated to be over 70% higher than those in nanocomposite...

Casting is an economical way to manufacture parts. On average, complex aerospace castings incur about one-fourth the cost of forgings. However, castings can not be used as primary structure in aircraft because of poor control over design allowables for the material strength and ductility. They can be used as secondary structure, but must include significant safety factors usually between 3 and ...

Nano-twinned copper exhibits an unusual combination of ultrahigh strength and high ductility, along with increased strain-rate sensitivity. We develop a mechanistic framework for predicting the rate sensitivity and elucidating the origin of ductility in terms of the interactions of dislocations with interfaces. Using atomistic reaction pathway calculations, we show that slip transfer reactions ...

Boron carbide (B4C) is a hard material whose value for extended engineering applications such as body armor; is limited by its brittleness under impact. To improve the ductility while retaining hardness, we used density functional theory to examine modifying B4C ductility through microalloying. We found that replacing the CBC chain in B4C with Si-Si, denoted as (B11Cp)-Si2, dramatically improve...

This paper describes finite element simulations of the structural deformation and material fracture behaviour high-strength steel RHS K gap truss joints. The fundamental scope was to examine whether joint strength predictions based on lower more ductile with a yield stress 355 MPa or less would hold good for higher 450 ductility. FEA reliability analysis indicates that failure modes associated ...

Based on tests on six L-shaped RC columns with 500 MPa steel bars, the effect of axial compression ratios and stirrup spacing on failure mode, bearing capacity, displacement, and curvature ductility of the specimens is investigated. Test results show that specimens with lower axial load and large stirrup characteristic value (larger than about 0.35) are better at ductility and seismic performan...

Nanostructured bainite is a novel ultra-high-strength steel-concept under intensive current research, in which the optimization of its mechanical properties can only come from a clear understanding of the parameters that control its ductility. This work reviews first the nature of this composite-like material as a product of heat treatment conditions. Subsequently, the premises of ductility beh...

This paper reports the results of an experimental investigation into the effects of incorporating varying amounts of expanded polystyrene beads on the engineering properties of high-strength concrete. It was observed that a density reduction of 8.3% caused compressive strength, tensile strength and modulus of elasticity to reduce by 48%, 39% and 15%, respectively. Drying shrinkage was marginall...