This study is focused on isothermal and anisothermal precipitation of M23C6 carbides from the fully ferritic structure (γ + δ) austenitic-ferritic duplex stainless steel X2CrNiMo2253, (2205). During heat treatments, small particles K-M23C6 carbide precipitates at δ/δ grain-boundaries. Their formation precedes γ σ-phases, by acting as highly potential nucleation sites, confirming undertaken TEM ...

Examination of a time–temperature–transformation (TTT) diagram for an eutectoid carbon steel (Fig. 1), bearing in mind the fact that the pearlite reaction is essentially a high temperature one occurring between 550C and 720C and that the formation of the martensite is a low-temperature reaction, reveals that there is a wide range of temperature ∼250–550C within which neither of these phases for...

The effects of boron on the grain boundary and surface energies in iron at 900 and 1000 OC and AISI 316 stainless steel in the temperature range 950-1 250 OC were investigated. It was found that boron reduced these energies in a manner typical of an element with low solubility in the matrix. It has been found that boron improves the grain boundary strength of iron at low temperatures [I] and in...

Due to the complexity and uncertainty in the process, the soft computingmethods such as regression analysis, neural networks (ANN), support vector regression (SVR), fuzzy logic andmulti-gene genetic programming (MGGP) are preferred over physics-based models for predicting the process performance. The model participating in the evolutionary stage of the MGGP method is a linear weighted sum of se...

The joining of a 6-mm thickness Al 6061 to AISI 1018 steel has been performed by the combined effects of fusion and solid state welding. The process is derived from friction stir welding (FSW) but with an adjustable offset of the probe location with respect to the butt line. Metallographic studies by optical microscopy, electron probe microscopy, and the utilization of the X-ray diffraction tec...

In order to produce any product with desired quality by machining, proper selection of process parameters is essential. This can be accomplished by Full Factorial method. The aim of the present work is to investigate the effect of process parameter on surface finish and material removal rate (MRR) to obtain the optimal setting of these process parameters and the analysis of variance is also use...

Hardness of the widely used structural steel is of vital importance since it may help in the determination of many mechanical properties of a material under loading situations. In order to obtain reliable information for design, properties homogeneity should be validated. In the current study the hardness variation over the different diameters of the same AISI 4140 bar is investigated. Measurem...

In this study, the effects of cutting edge geometry, workpiece hardness, feed rate and cutting speed on surface roughness and resultant forces in the finish hard turning of AISI H13 steel were experimentally investigated. Cubic boron nitrite inserts with two distinct edge preparations and throughhardened AISI H13 steel bars were used. Four-factor (hardness, edge geometry, feed rate and cutting ...