Abstract: A system is configured for machining a workpiece (100), the workpiece includes an interior surface (110) that defines an internal passage (112). The system includes an electrode (116) located within the internal passage and electrically isolated from the workpiece, an electrolyte supply, a power supply, and a remover. The electrolyte supply is configured for circulating an electrolyte in a gap between the electrode and the workpiece. The power supply is configured for applying a voltage between the electrode and the workpiece to facilitate smoothing the interior surface. The remover is configured for completely removing the electrode from within the internal passage after smoothing the interior surface.

Abstract: Methods of making metal objects are provided. These methods generally involve adding a metal powder slurry into a sacrificial mold, such as a mold made by three dimensional printing, and heating the slurry/mold mixture. The heating steps may include curing the slurry to make a green part inside the mold, debinding to burn off the mold and binder to make a brown part, sintering, and hot isostatic pressing. Metal products, such as aircraft engine parts, are also provided.