This paper presents the results from an experimental and theoretical analysis of the thermomechanical behaviour of a metastable P-phase single crystal alloy of composition Cu 28.3at% A1 3.8at% Ni. The stress-strain behaviour of this single crystal material was investigated experimentally by tensile testing and this data was used to characterise the stress1 temperature martensite phase equilibri...

In laser forming, phase transformations in the heat-affected zone take place under steep thermal cycles, and have a significant effect on the flow behavior of Ti–6Al–4V alloy and the laser-forming process. The flow-stress data of a material are generally provided as only dependent on strain, strain rate, and temperature, while phase transformations are determined by both temperature and tempera...

Austenitic stainless steels are extensively used in various applications requiring good corrosion resistance and formability. In the current study, the formation of nano/ ultrafine grained austenitic microstructure in a microalloyed AISI 304L stainless steel was investigated by the advanced thermomechanical process of reversion of strain-induced martensite. For this purpose, samples were subjec...

Flash processing is a new heat treatment process being developed to produce steel with relatively high strength and ductility. It involves rapidly heating steel sheet or strip to a temperature in the austenite range and quenching; the entire thermal cycle takes place within 15 seconds. The resulting microstructure is fine and difficult to resolve using standard metallographic techniques. In thi...

  Abstract   Recovery and recrystallization phenomena and effects of microalloying elements on these phenomena are of great importance in designing thermomechanical processes of microalloyed steels. Thus, understanding and modeling of microstructure evolution during hot deformation leads to optimize the processing conditions and to improve the product properties.   In this study, finite element...

The current study applied thermomechanical processing (TMP) on 301 austenitic stainless steel to produce an ultrafine-grained structure, examining the dual effects of deformation at subzero temperature and TMP cycles strain-induced α′-martensitic transformation austenite reversion occurring upon subsequent annealing. Three schemes were adopted: (1) one cycle using a strain 0.30, (2) two 0.20, (...

the pseudo-elastic behavior of shape memory alloy (sma) truss and cantilever beam are investigated. brinson’s one-dimensional material model, which uses the twinned and detwinned martensite fractions separately as internal variables, is applied in the algorithm to establish the sma stress-strain characteristics. this material model also incorporates different young’s modulus for austenitic and ...

The formation of nano/ultrafine grained ferrite in low carbon steels containing different amounts of niobium was investigated using thermomechanical treatment which consisted of annealing of 85% cold rolled martensite with different parameters. The specimens were characterized by optical and scanning electron microscopy and Vickers hardness test. A lamellar dislocation cell structure was formed...