Focused Ion Beam Milling and Imaging: An Advanced Method to Detect Fine Inclusions in Cast Aluminium Alloys

摘要

The combined function of a FIB milling technique utilising beam sizes of under 10 nm coupled with a micromanipulator and FIB imaging enables analysis of the microstructure of samples and fabrication of TEM thin foils. This is accomplished at desired locations in the same chamber without moving the sample or any mechanical sawing and thinning. In this study, the FIB milling and imaging technique was used to examine the microstructure and chemical composition of fine inclusions in an Al alloy, which are generally difficult to detect by conventional optical and/or scanning electron microscopy due to their size and volume fraction. Examples are presented of fine particles in cast commercial purity aluminium and a melt conditioned AA 5754 alloy.