Optimization Of ART Heat Treatment Process Of Rare Earth Medium Manganese Steel

In this study,a rare-earth Mn steel of composition 0.14C-5Mn-1Al-Ce was designed based on the idea of multi-phase,multi-scale,metastable microstructure regulation.Heat treatment experiments were carried out on the rare-earth Mn steels of this composition to systematically study their microstructure evolution and mechanical properties in order to optimize the heat treatment process of the rare-earth Mn steels of this composition.The study shows that in the ART annealing process at different temperatures,the microstructure exists trace carbide at lower temperature ART annealing,the carbide dissolves at higher ART temperature and the microstructure becomes fine,while the ART temperature increases and the inverse phase transformation austenite content reaches its peak at 640°C.The overall trend is to rise first and then fall,and the strong plastic product of the specimen also shows a trend consistent with the inverse phase transformation austenite content.In the different time ART annealing process,the carbide dissolves with the extension of ART time,the inverse phase transformation austenite content reaches its peak at 4h,and the strong plastic product of rare earth manganese steel also reaches the peak 34.209Gpa-%,and its overall trend is rising first and then decreasing.Based on the optimization of the ART heat treatment process with different annealing temperatures and times,two-step annealing and cyclic ART annealing experiments were carried out,which showed that the mechanical properties of the experimental steel would stabilize in a horizontal zone after the two-step annealing.After short time cyclic annealing,the mechanical properties of the experimental steel are enhanced with the increase in the number of cycles,and three cycles is the best solution,while the tensile strength will increase after long time cyclic annealing,but the strong plastic product will continue to become lower.The reverse phase transformation austenite content at room temperature affects the mechanical properties of manganese steels in rare earths.The reverse phase transformation austenite content is directly related to the deformation induced phase transformation(TRIP)effect,and the higher the reverse phase transformation austenite content,the more pronounced the TRIP effect and the better the mechanical properties of manganese steels in rare earths.