The size-temperature "phase diagram" for small Lennard-Jones clusters LJn (n< or =147) is constructed based on the analysis of the heat capacities Cv(T) , computed by the parallel tempering Monte Carlo method. Two types of "phase transitions" are often observed: the higher-temperature solid-liquid transition, due to melting of the cluster core, and the lower-temperature melting that occurs with...

We present a Monte Carlo algorithm that facilitates efficient parallel tempering simulations of the density of states g(E) . We show that the algorithm eliminates the supercritical slowing down in the case of the Q=20 and Q=256 Potts models in two dimensions, typical examples for systems with extreme first-order phase transitions. As recently predicted, and shown here, the microcanonical heat c...

Parallel tempering Monte Carlo and multihistogram methods are combined to study the phase changes of the water octamer. The heat capacity is calculated continuously from very low temperatures up to T5230 K. We find the melting temperature to be 178.5 K. In addition, a solid–solid phase change is found at 12 K. We introduce an order parameter to monitor this low temperature phase change. © 2001 ...

Abstract Laser directed energy deposition (L-DED) was used to produce samples of the newly patented W360 hot work tool steel by Böhler. The process parameters were optimized obtain nearly fully dense through production and analysis single deposited tracks layers. Subsequently, bulk underwent a hardening heat treatment, consisting austenitizing, air quenching, tempering. analysed in as-built con...

This study aims to determine the effect of hardening and tempering on tensile strength (ASTM E 8) hardness (Rockwell) applied medium carbon steel. The heat treatment process is heated by a furnace at temperature 900 °C 920 then held for 30 minutes cooled quickly further processed Tempering with each being tempered 500 slowly. results obtained are in variation °C, value increases from raw materi...

Simulated and parallel tempering are families of Markov Chain Monte Carlo algorithms where a temperature parameter is varied during the simulation to overcome bottlenecks to convergence due to multimodality. In this work we introduce and analyze the convergence for a set of new tempering distributions which we call entropy dampening. For asymmetric exponential distributions and the mean field I...

Abstract The present contribution concentrates on the different effects of Si and Al carbide precipitation austenite decomposition during Q&amp;P-process an additional galvannealing treatment up to 560 °C. These have been investigated by dilatometry (derivation relative length change) differential scanning calorimetry (heat flow) tempering. It was possible show beneficial effect retarding in te...

The effect of Cu and Si contents on the evolution embrittlement during a heat treatment consisting quenching into an oil bath tempering in range 200–500 °C was investigated medium-carbon steels with 0.48 w/% 0.57 C. results showed that higher silicon content shifted tempered martensite to temperatures. alloyed had lower notch-toughness values, which worsened increasing temperature compared Cu-f...

in multi-stage drying of various rough rice varieties, determination of the optimum drying and tempering conditions is important to accelerate the operation and reduce energy consumption, as well as produce a high quality product. in this research, two rice varieties namely, shafagh (long-grain) and sazandegi (medium-grain) were dried under high (air temperature and relative humidity of 60°c an...