Method for simulating precipitation of low-alloy high-strength steel titanium carbide

Abstract

The invention relates to a method for simulating precipitation of low-alloy high-strength steel titanium carbide. Molecular dynamics is adopted for simulation, and the simulation is realized by Lammpssoftware. The method includes six steps of establishment of a ferrite matrix, establishment of a titanium carbide nucleation precipitation site, realization of a titanium carbide precipitation equilibrium system, setting of titanium carbide precipitation control conditions, titanium carbide cluster precipitation, and data collection and analysis. Compared with the prior art, the invention has thebeneficial technical effects that: (1) a simulation method for titanium carbide cluster precipitation in an iron matrix is established, thereby realizing the research on the titanium carbide precipitation mechanism of low-alloy high-strength steel at the atomic level, revealing the titanium carbide precipitation mechanism, and making up the defect of a macroscopic experiment; (2) the relationshipbetween the size and quantity of titanium carbide in the low-alloy high-strength steel is established, which is very important for the study of the low-alloy high-strength steel at the atomic level;and (3) the computational amount of a general numerical simulation method is reduced, and the computational cost is also reduced.

Description

technical field [0001] The invention relates to the field of metal materials, in particular to a method for simulating precipitation of titanium carbide in low-alloy high-strength steel. Background technique [0002] Low-alloy high-strength steel (HSLA steel) is based on ordinary carbon steel with a carbon content of less than 0.20%, and by adding alloy elements not higher than 2.5%, it has a better performance than ordinary carbon structural steel. mechanical properties. The mechanical properties of low-alloy high-strength steel are closely related to the precipitation behavior of the second phase of alloying elements. During the solidification and cooling process of the low-alloy high-strength steel slab, elements such as V, Ti and Nb are precipitated in the form of carbides. The precipitation of these second-phase compounds changes the microstructure of the low-alloy high-strength steel and directly affects the hardness and toughness of the steel. Due to the small size...

AI Technical Summary

Problems solved by technology

[0006] (1) Numerical models can predict the growth and decomposition of carbonitride clusters and precipitates to some extent, but these studies focus on the time evolution of carbide growth and cannot describe the formation mechanism of carbides in alloy steels

Although classical nucleation theory plays an important role in the study of second-phase precipitation, this method cannot accurately predict the nucleation of second-phase clusters due to its parametric factors depending on the concentration of nucleation sites that cannot be precisely predicted

[0007] (2) The Monte Carlo simulation method has a large limit on the size of the simulation system, which cannot meet the environmental requirements for the precipitation of carbides of alloying elements

However, the current molecular dynamics model with precipitates as the research object focuses on the binary alloy system, and it is still unable to explain the precipitation mechanism and precipitate characteristics of the carbide in the iron-alloying element-carbon ternary system.