Sulfur-free Surfactant for Carbide Nanoparticle Characterization in Steel Using Asymmetric Flow Field-Flow Fractionation Hyphenated Inductively Coupled Plasma-Mass Spectrometry.

An asymmetric flow field-flow fractionation (AF4) combined with inductively coupled plasma mass spectrometry (ICP-MS) was applied to measure the concentration and size distribution of nanometer-sized carbides in steel sheets, such as titanium carbides (TiC) and vanadium carbides (VC). Prior to AF4-ICP-MS measurement, TiC and VC nanoparticles in steel were extracted into a solution via selective potentio-static etching by electrolytic dissolution (SPEED) method. The SPEED method enabled the selective dissolution of iron and the carbide nanoparticles were dispersed as primary particles in solution with surfactant.