Microscopic Parameters of Scanning Electron Microscope Image of Steel Structure

  • Gen Li
Keywords: Steel Structure Microscope, Image Analysis, On-Look Parameters, Q345-Q390 Steel Structure Cemented Carbide

Abstract

In the traditional two-dimensional microstructure characterization, the linear intercept on the scanning electron
micrograph (SEM) is the most commonly used measurement method to determine the carbide grain size and
adjacency in the Q345-Q390 steel structure cemented carbide, But this requires cumbersome and subjective
measurements, and strictly depends on the quality of micrographs and the determination and definition of grain
boundaries. Steel structure cemented carbide is a composite material composed of hard phase Q345 and bonding
phase Q390 with large differences in properties. Therefore, its mechanical properties include information such
as integral number of receivers, grain size, adjacency and grain distribution Significant influence. Therefore, the
microstructure characterization of Q345-Q390 steel carbide is very important. This article uses an automatic
image analysis program with two key technologies, namely the maximum category variance method and an
improved watershed algorithm. This method is used for Q345-16Q390 Carbide image analysis can easily obtain
consistent microstructure parameters. Then two different methods of quantity weighting and area weighting are
used to characterize the average grain size of Q345. In this paper, the finite element method is used to
numerically analyze the stress and strain of the microstructures of four Q345-Q390 composites with different
grain sizes under tensile load. And the statistical results simulate the values of the equivalent Young's modulus
and its equivalent Poisson's ratio, and the obtained parameters are in accordance with the models of
Hashin-Shtrikman and Zimmerman, thus proving the consistency of the conclusions. And from the technical
level to explore and solve the accuracy of the finite element method, provides a new idea and new method for
the microscopic parameter simulation of Q345-Q390 cemented carbide. The experimental results show that the
predicted value of the equivalent Poisson's ratio is in good agreement with the relationship between the upper
and lower limits of Zimmerman. The overall trend of the equivalent Poisson's ratio increases with the increase
of the Q390 content.

Published
2020-04-01