Abstract: The properties of SMA (Shape Memory Alloys, that are smart materials) are associated to a first order phase transition named martensitic transformation that occurs between metastable phases: austenite and martensite. At upper temperature or at lower stress the austenite is the metastable phase. The martensite appears at lower temperature or higher stresses. The hysteresis of the trans...

We introduce the Gaussian process model for the empirical modelling of the formation of austenite during the continuous heating of steels. A previous paper has examined the application of neural networks to this problem, but the Gaussian process model is a more general probabilistic model which avoids some of the arbitrariness of neural networks, and is somewhat more amenable to interpretation....

The influence of external stresses on the transformation behaviour has been studied for a polycrystalline Fe-3 IMn-SSi alloy exhibiting the y-+& martensitic transformation. Samples have been loaded at temperatures above the M, temperature, cooled with a constant external load to a temperature below the M, temperature and subsequently heated without load to a temperature above the A, temperature...

*Member of ASM International arburizing has been a popular method for obtaining a unique balance of properties in steels for many years. Steels with low carbon contents are characterized by good toughness and good ductility, but low strength and low wear resistance. By locally increasing the carbon content at the surface, followed by heat treatment to produce a very high hardness in this layer ...

The influence of thermomechanical deformation on the residual stresses caused by quenching in bar shaped specimens of heat treatable steel 42CrMo4 has been investigated using a mechanical method for detemining the distribution of residual stresses of the first kind. The results obtained show that the residual stress distribution after quenching is dected by the strengthening and softening of th...

Bainitic reaction kinetics in ductile iron contained according to Ukrainian standard (weight %) 3.603.80 carbon, 2.60-2.80 Si, 0.12 Mn, 0.60 Cu and additionally alloyed by Mo (0.15-0.20) has been studied. It was found that the overall transformation kinetics becomes slower as transformation temperature increase. This is because more intensive redistribution of carbon into austenite at higher te...

Duplex stainless steels (DSSS) have a microstructure composed of ferrite and austenite phases that gives them a very good combination of mechanical and corrosion properties. These steels are desirable for many applications in the chemical and petrochemical industries. In the present study, a type of stainless steel was cast, solution annealed at 1200°C for 60 min and then quenched in water. Ini...

In the present research, the effect of the homogenization process and annealing temperature were investigated for the 1.4470 ferritic-austenitic stainless steel in the as-cast condition. In this regard, microstructural evolutions, hardness, and impact energy of the steel was evaluated with different heat treatment conditions. The results show that the minimum volume fraction of austenite phase ...

Victor H. C. Albuquerque & Rodrigo Y. M. Nakamura & João P. Papa Cleiton C. Silva & João Manuel R. S. Tavares Universidade de Fortaleza, Centro de Ciências Tecnológicas, Fortaleza, Brazil Departamento de Computação, UNESP Univ Estadual Paulista, Bauru, Brazil Departamento de Engenharia Metalúrgica e Materiais, Universidade Federal do Ceará, Fortaleza, Brazil Universidade do Porto, Faculdade de ...