The formation of precipitates, especially along austenite grain boundaries, greatly affects the formation of transverse cracks on the surface of continuous-cast steel. The steel composition and cooling history influences the formation of precipitates, and the higher temperature and corresponding larger grain growth rate under oscillation marks or surface depressions also have an important effec...

We perform atomistic Monte Carlo simulations of bending a Lennard-Jones single crystal in two dimensions. Dislocations nucleate only at the free surface as there are no sources in the interior of the sample. When dislocations reach sufficient density, they spontaneously coalesce to nucleate grain boundaries, and the resulting microstructure depends strongly on the initial crystal orientation of...

Four principal factors contribute to grain-boundary strengthening: (a) the grain boundaries act as barriers to plastic flow; (b) the grain boundaries act as dislocation sources; (c) elastic anisotropy causes additional stresses in grain-boundary surroundings; (d) multislip is activated in the grain-boundary regions, whereas grain interiors are initially dominated by single slip, if properly ori...

The fracture of polycrystalline graphene is explored by performing molecular dynamics simulations with realistic finite-grain-size models, emphasizing the role of grain boundary ends and junctions. The simulations reveal a ~50% or more strength reduction due to the presence of the network of boundaries between polygonal grains, with cracks preferentially starting at the junctions. With a larger...

The Potts model of grain growth was adapted for the purpose of simulating abnormal grain growth (AGG) resulting from grain boundary complexion transitions. The transition in grain boundary structure between specific complexion types results in changes in properties. Where the transitions decrease energy and increase the mobility of boundaries, AGG occurs provided that such transitions predomina...

An ultrafine grain surface layer with average crystallite size of 28 nm was produced on annealed mild steel through a wire brushing process. The effects of grain size reduction on the inhibition performance of sodium phosphate were investigated using polarization and electrochemical impedance spectroscopy (EIS) measurements. The crystal grain size of wire brushed surface was analyzed by X-ray d...

grain discoloration caused by fungi agents, in crop season that the mature grain stage coincides with rain, it causes many damages. in this research effect of paddy discoloration of three varieties (hashemi, gohar and khazar) and disease index in two levels (high and low disease index levels) on grain apparent quality, milling properties and grain bending strength was investigated in a factoria...

In this article, the crack growth driving force and the resistance to cleavage cracking associated with crack front transmission across a high-angle grain boundary in a silicon thin film are analyzed, and a closed-form solution of grain boundary toughness is obtained. It is noticed that the fracture resistance of the grain boundary is a function of the film thickness. This size effect is attrib...