In this contribution the precipitation and transformation processes at various aging times in the temperature range 873 – 1573 K were studied. The precipitation of the sigma phase was observed after just 3 min of aging, and after 30 min of aging at around 1053 K its fraction exceeded 40 %. An intensive austenitetoferrite transformation was observed above 1423 K. Optical microscopy, EDS, EBSD, XRD as well as microindentation hardness, hardness, impact toughness and tensile tests were carried out in order to evaluate the obtained microstructures of aged samples.
COBISS.SI-ID: 1039199
The hot deformation behavior of as cast 30Cr10Ni duplex stainless steel was investigated with the aim to better understand the conditions that lead to the occurrence of cracking. The results indicate that in the temperature range 14231523 K the ascast microstructure exhibits increased workability, while below this temperature the microstructure is prone to cracking. As such, the microstructure should be crushed in the high temperature range in order to avoid the occurrence of cracking.
COBISS.SI-ID: 1057375
In this paper a neural networklike approach that accounts for the different uncertainties in the hot extrusion of AA6082 alloys is given. The results, presented in the form of scrap/supply curves, suggest the use of a probabilistic approach in the process of hot extrusion. The proposed approach considers both the epistemic and aleatory uncertainties and takes into account all the available influential input variables. It was found that mechanical properties and the yield can be additionally optimized by reducing the epistemic uncertainties, which consequently requires more accurate measurements and more reliable control of the production processes.
COBISS.SI-ID: 1168223
This article is concerned with the finite element implementation of an elastoviscoplastic constitutive model using a symbolic approach. The numerical examples derived for polyethylene terephthalate (PET) polymers demonstrate that symbolic systems can be applied to develop complex constitutive models capable of simulating material responses that are in good agreement with experimental measurements over a wide range of strain rates, temperatures, and loading conditions.
COBISS.SI-ID: 5006433
The effect of Ce addition on the AA A360 (Al–10%Si–0.5%Mg) alloy was investigated using equilibrium thermodynamic calculation, thermal analysis, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The purpose is to study the variations that occur during solidification and precipitation with different Ce additions, as well as their effect on the mechanical properties. The results show that the Ce addition decreases the eutectic (αAl + Mg2Si) temperature. The solidus temperature also decreases with the increasing Ce addition. The precipitation enthalpy determined using DSC decreases with the Ce addition, while precipitation takes place more rapidly and intensively, indicating increased reaction kinetics. The mechanical properties like hardness and tensile strength also increase with the Ce addition. The phase that contributed to the hardness of the investigated alloy was composed of Al, Ce, Mg and Si.
COBISS.SI-ID: 1133407