Comparison between magnetic force microscopy and electron back-scatter diffraction for ferrite quantification in type...

Area of Science:

• Materials Science
• Metallurgy
• Analytical Chemistry

Background:

• Several analytical techniques exist for characterizing steel microstructures, including austenite, ferrite, and precipitate phases.
• Magnetic Force Microscopy (MFM) offers selective detection of ferromagnetic phases, making it valuable for stainless steel microstructural studies.

Purpose of the Study:

• To compare Magnetic Force Microscopy (MFM) and Electron Back-Scatter Diffraction (EBSD) for morphological mapping and quantification of ferrite in steels.
• To investigate the critical role of sub-surface measurement depth in the comparison of MFM and EBSD.

Main Methods:

• Application of Magnetic Force Microscopy (MFM) for local microstructure analysis.
• Utilizing surface shielding techniques to determine MFM measurement depth.
• Comparison of MFM and Electron Back-Scatter Diffraction (EBSD) capabilities.

Main Results:

• The sub-surface measurement depth was identified as a critical factor in comparing MFM and EBSD for ferrite quantification.
• Magnetic Force Microscopy (MFM) demonstrated a measurement depth of 105-140 nm when employing surface shielding.
• Differences in measurement depth influence the morphological mapping and quantification accuracy of both techniques.

Conclusions:

• The study highlights the importance of considering measurement depth when selecting between MFM and EBSD for steel microstructure analysis.
• MFM's ferromagnetic selectivity and defined measurement depth provide valuable insights into local steel microstructures.
• Both MFM and EBSD possess distinct capabilities and limitations that must be understood for accurate phase analysis in steels.