Extremely Strong Steels — The Mechanism and Prevention of Hydrogen Embrittlement
(Room 201)
08 May 17
8:00 AM
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8:30 AM
Tracks:
Howe Memorial Lecture
The metallic bond in steel is wonderful in the sense that it allows the movement of atoms over large distances while maintaining the glue between the atoms, making the material incredibly tolerant to defects.
Nevertheless, metals do suffer from the presence of unintended impurities, and the problem is particularly pernicious when the steel is strong. Hydrogen, which is the smallest atom in existence, can enter the iron through the electrochemical processes accompanying corrosion, or when attempts are made to uniformly protect the steel using imposed countercurrents (cathodic protection). This lecture will describe the most likely mechanisms by which this minute atom can change the macroscopic properties of steel, and then go on to show how metallurgists can design steels and components that resist hydrogen embrittlement by reducing the intake of hydrogen or by rendering it innocuous when it does penetrate the steel.