Effect of heat treatment on mechanical properties and structure of high-strength pipe steels with a ferrite-bainite structure
The effect of heat treatment on mechanical properties and microstructure of high-strength low-alloy ferrite-bainite pipe steels is studied. Specimens are heated in a laboratory furnace up to a temperature in the range 100–850°C. Dependences for the change in mechanical properties on heating temperature and the main features of steel structure are determined. TEM is used to study excess phase precipitation, including Nb and V carbonitrides, during heating. Unfavorable temperature ranges are determined for heating pipe steels with a ferrite-bainite structure. The results obtained may be used in industrial production and during development of new technology for thermomechanical treatment.
Keywordsheat treatment pipe steels ferrite-bainite microstructure carbonitride precipitation TEM method
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