color metallography is a useful method for characterizing microstructures of steels with multiple phases. in this paper, application of three different color etching techniques for a bainitic-martensitic steel is reported. comparisons between the results showed that 10% na2s2o5 aqueous solution was the best etchant for distinguishing martensite, bainite and ferrite phases. the obtained microgra...

Machining through turning was carried out in a lathe to study the chip formation of Multiphase Ferrite (F-B-M) microalloyed steel. Taguchi orthogonal array was employed to perform the machining. Continuous and discontinuous chips were formed for different cutting parameters like speed, feed and depth of cut. Optical and scanning electron microscope was employed to identify the chip morphology. ...

A mechanistic model was developed for predicting carbon dioxide corrosion rates of carbon steel pipes in multiphase flow conditions. The model incorporates the chemistry, thermodynamics of carbon dioxide dissolution, multiphase mass transfer, electrochemical kinetics on the metal surface and the presence of a corrosion product film. The predicted corrosion rates show good agreement with the exp...

The transport of fluid, heat ,and particles (bubbles and solid inclusions) in flowing molten steel is investigated in steel refining ladles, the continuous casting tundish, continuous casting mold and strand, and steel ingot casting processes. The two-equation k-ε model is used to simulate the turbulence. Multiphase fluid flow is numerically simulated with a Lagrangian-Eulerian approach, an Eul...

The possibility to obtain multiphase steels with considerable fractions of retained austenite, which is of key interest for the occurrence of the TRIP effect, is investigated in steels with low amounts of Si and Al. Special emphasis is dedicated to the microstructural observation of this phase, since its volume fraction, distribution and stability, related to the carbon content, will determine ...

There are multitudinous, multispecies, nonlinearity, multiphase and so on complex system time and space scales characteristics in steel plate production process, whose defects are divided into dominant defects and hidden defects. Real-time dynamic steel plate defects information can not be effectively and quickly converted, it is difficult to find the relationship among defects facts, defects r...

Modern vehicle bodies make intensive use of high strength steel grades to meet the contradicting demand of lighter weight and simultaneously better mechanical performance. For many steel grades microalloying by niobium is the key to achieve their characteristic property profile. In HSLA steels niobium enhances the strength primarily by grain refinement. In interstitial free high strength steels...

The optimal material processing in steel industry is difficult because of the multi-constituent and multiphase character of the commercial steels, variety of the possible processing paths, and plant specific equipment characteristics. This paper shows implementation of the genetic programming approach for crack presence modeling after rolling. The data (110 samples covering 7 different steel gr...

modern vehicle bodies make intensive use of high strength steel grades to meet the contradicting demand of lighter weight and simultaneously better mechanical performance. for many steel grades microalloying by niobium is the key to achieve their characteristic property profile. in hsla steels niobium enhances the strength primarily by grain refinement. in interstitial free high strength steels...