Elastic emission machining (EEM) can be thought of as a machining method utilizing the chemical activity of a particle surface, rather than a liquid etchant as in chemical etching. Different combinations of workpiece materials and powders affected removal rates strongly, so that the machining process was considered from the standpoint of the atomic interactions at the interface between the workpiece and the powder particles. The surface voltage of the workpiece with adsorbed powder particles was measured as one of the parameters representing the interfacial interactions, and correlations with removal rates were obtained.