Medienproduktion

Eintrag vom: 23.02.2013.

AISI 4340 steel (UNS G43400) is an ultra-high strength medium carbon low alloy steel which combines deep hardenability high ductility toughness and strength and has high fatigue resistance and creep resistance.

 

The tempering process changes the microstructure of AISI 4340 steel from marten-site to bainite wherein the increase in holding time from 2 3 and 4 h tends to decrease the number of bainite phases.

 

The AISI 4340 steel is heat treated for dual phase structure with prior normalizing treatment. The treated specimens are tested for mechanical properties along with microstructure.

 

We investigated the evolution of microstructure and mechanical properties AISI 4340 steel during high-energy ball milling spark plasma sintering (SPS) and post heat treatments.

 

AISI 4340 steel was deposited using cold spray (CS) and laser-assisted cold spray (LACS) techniques at different surface temperatures of 500 738 and 950 °C. To study the microstructure evolution and phase transformation scanning electron microscopy and x-ray diffraction were used on both the starting powders and the CS and LACS deposits.

 

Ce guide décrit en détail la composition les propriétés mécaniques les méthodes de traitement thermique les traitements de surface et les utilisations réelles de l'acier 4340. Il aide les concepteurs les ingénieurs et les fabricants à faire des choix judicieux pour les pièces à haute performance et à charge critique.

 

Scanning electron microscopy revealed a predominantly martensitic microstructure for all processing parameters examined although X-ray diffraction revealed the minor presence of retained austenite within the as-fabricated 4340 steel.

 

This study presents a novel approach to predict surface roughness in the hard turning of AISI 4340 steel using carbide tools aimed to develop a comprehensive predictive map.

 

We investigated the evolution of microstructure and mechanical properties AISI 4340 steel during high-energy ball milling spark plasma sintering (SPS) and post heat treatments.

 

In order to prevent this fault a study on the microstructure and mechanical properties of AISI 4340 steel under different tempering conditions becomes necessary these questions being focused on in this study.