Bainite auctile iron isothermal quenching technology

Abstract

An isothermal quenching technology for the nodular graphite cast iron of bainite includes such steps as heating to bainite temp region, holding the temp for a certain time, cooling in water, cooling in isothermal furnace, and cooling in air. Its advantages are high quality of product, no pollution, and low cost.

Description

technical field [0001] The invention relates to a quenching process for bainite ductile iron, in particular to an isothermal quenching process for bainite ductile iron using water as a quenching medium. Background technique [0002] Bainitic ductile iron has comprehensive mechanical properties of high strength, plasticity and toughness, which is significantly better than that of spheroidic-ferritic ductile iron, and also superior to ductile cast iron that has been quenched and tempered. For example, its tensile strength can reach 1000Mpa and its elongation can reach 10%. In particular, this cast iron has high bending fatigue strength and good wear resistance. Therefore, the emergence of austempered bainitic ductile iron is known as one of the major achievements in cast iron metallurgy in the past 40 years. However, the commonly used austempering bainitic ductile iron process has the following problems: [0003] 1. At present, the main development is salt bath isothermal q...

AI Technical Summary

Problems solved by technology

[0007] The present invention aims to solve the problem that salt bath is unfavorable for processing in current austempering bainite ductile iron process, and also causes pollution, and the cost increases after adding alloy elements, and provides a processing technology using water as the medium, which has the advantages of Pollution, the structure and performance of the obtained product can be controlled, and the quality is reliable, etc.