Nano Particles Effect on Transformation Behavior and Mechanical Properties on Commercial Steel Used for Automobile Parts

Abstract

A scientific study has been performed in this research work on the basis of experimental results and ramification to divulge the advancement of second phase particles and its influence on ferrite and austenite phase transformation in less carbon-manganese added steel. Two steels have been engaged in this competition with and without aluminum addition along with nitrogen. To fade out the already present particles, as received steel under investigation was solution heat treated at 1200°C and then both the steel samples were heat treated at 750°C and 810°C for 15, 20, 35, and 70 sec incubation time in the cyanide added liquid bath furnace and were rapidly cooled from elevated temperature at room temperature in ordinary water. Metallography was performed after etching technique in two etchant solutions microstructural features with advanced Olympus optical microscope with polarized light. To further enlarge the important microstructure SEM was used to capture the micrographs. It was concluded that aluminum combine with nitrogen stimulate the fine aluminum nitride (AlN) particles and these particles were the major source to hinder the grain boundary mobility and consequently phase transformation was interrupted in aluminum added steel and it lowers the critical temperatures. Surprisingly there was no such attitude was observed in without aluminum added steel.

Keywords

• Phase transformation
• AlN-nano particles
• Austenite
• aluminum