Microtreatment of Iron-Based Alloy, Apparatus and Method Therefor, and Microstructure Resulting Therefrom

Abstract

This invention relates to a multi-phase transformation of an iron and carbon-containing alloy. While the phenomena for this cooling transformation are not fully understood, multiple theories are present. The first theory is that since the alloy is rapidly heated and carbon leveling has not occurred, carbon enriched areas transform to a first phase, perhaps martensite, while lesser carbon areas may transform to a second phase, perhaps bainite. Thus a dual phase alloy is produced.

1 . A metal treatment process for transforming an iron-containing alloy into a high strength steel, comprising:
 rapidly heating the alloy to at least about 1650 degrees C., immediately quenching the alloy at a rate of from about 10,000 degrees C., whereby two temperature ranges have transformations occurring during the single quenching operation, first transformation occurs from 650C to 550C and second transformation occurring from 470C to 360C during cooling.