In-situ EBSD observation method for microscopic orientation evolution of recrystallized grains of magnesium alloy

Abstract

The invention belongs to the field of metal material structure analysis sample preparation and structure observation characterization, and particularly relates to an in-situ EBSD observation method for microcosmic orientation evolution of recrystallized grains of magnesium alloy. The method comprises the steps of firstly, carrying out mechanical polishing on a magnesium alloy sample, then preparing indentation mark points on the surface to be detected, and conducting EBSD observation for the first time on a target area after ion etching; and taking out the sample, carrying out recrystallization annealing heat treatment and ion etching, finding the same area according to the indentation mark points, carrying out EBSD observation for the second time, and similarly, completing subsequent required in-situ EBSD observation. According to the method, in-situ tracking characterization of recrystallization nucleation, grain growth and microscopic orientation evolution in the same area in the recrystallization annealing process of the magnesium alloy is achieved, and the problems that the magnesium alloy is low in calibration rate due to a surface stress layer, an oxide layer and pollutants,accurate positioning cannot be achieved, and in-situ EBSD observation is difficult to achieve are solved. The process is simple and controllable, the technical requirements on sample preparation of experimenters are low, and the experiment success rate is high.

Description

Technical field [0001] The invention belongs to the technical field of preparation of metal material microstructure analysis samples and microstructure observation and characterization, and particularly relates to an in-situ EBSD observation method for micro-orientation evolution of magnesium alloy recrystallization grains. technical background [0002] Texture is the key factor affecting the mechanical properties of wrought magnesium alloys, and the relationship between the formation of non-basal texture and recrystallization is a hot research topic at present. The nucleation and grain growth (grain boundary migration) in the recrystallization process will affect the grain micro-orientation, and then affect the final texture type. Electron backscattering diffraction (EBSD) technology has been widely used in the study of the relationship between recrystallization and texture because it can accurately characterize the micro-orientation and distinguish the deformed grain from the r...

AI Technical Summary

Problems solved by technology

Among them, OP-S suspension polishing is easy to produce residual stress layer due to the use of hard particle polishing, which makes the sample calibration rate low

Electropolishing needs to set strict temperature, time, voltage and current parameters, and these parameters have a great influence on the magnesium alloy state (cast state, deformed state, annealed state, etc.), alloy composition (whether it contains rare earth elements, etc.) Two phases, second phase size and distribution, etc.) are sensitive, and it takes repeated trials to get the appropriate parameters. In addition, the experimental operator's proficiency in electrolytic polishing technology will also affect the polishing effect

Although the focused ion beam can cut a qualified sample without stress layer at a fixed point, the effective scanning area obtained is small and the price is expensive.

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