Microtreatment of carbide containing iron-based alloy and articles resulting therefrom

Abstract

Processes and apparatuses for micro-treating iron-based alloys to transform and/or shape them and the resulting materials obtained by treating low, medium, and high carbon steel and other iron-based alloys to form at least a mixed microstructure that may contain martensite, bainite and un-dissolved carbides, and may also contain complex steel microstructures including portions of bainite, coalesced bainite, acicular ferrite, retained austenite and/or martensite along with combinations thereof by micro-treating said iron based alloy.

What is claimed is: 
     
         1 . A metal treatment process for transforming an carbide containing iron based alloy into a high strength steel, comprising:
 rapidly heating the alloy to at least about 1000 degrees C. at a rate of 300° F./sec to 5000° F./sec from below the austenitic conversion temperature to a selected temperature above the austenitic conversion temperature,   substantially immediately quenching the alloy at a rate of from about 200 to 5,000 degrees F/s.,   whereby multiple transformations to multiple austenite daughter phases occur and at least a mixed microstructure results that may contain martensite, bainite and un-dissolved carbides, and may also contain complex steel microstructures including portions of bainite, coalesced bainite, acicular ferrite, retained austenite and/or martensite along with combinations thereof by micro-treating said iron based alloy.   
     
     
         2 . A microstructure of carbide containing iron based alloy, comprising:
 a mixed heterogeneous microstructure of a carbide containing iron based alloy having at least one austenite daughter phase containing at least one of martensite, bainite, un-dissolved carbides, coalesced bainite, acicular ferrite, retained austenite, or combinations thereof.