What does modern use instead of striking the iron?

Forging, the modern mechanical process closest to the ancient iron-striking process, is forging.

Forging is a processing method which uses forging machinery to exert pressure on metal blank to produce plastic deformation, so as to obtain forgings with certain mechanical properties, shapes and sizes. Forging is one of the two major components of forging (forging and stamping). Forging can eliminate as-cast porosity defects and optimize the microstructure of metal during smelting. At the same time, because the complete metal streamline is retained, the mechanical properties of forgings are generally better than those of castings of the same material. Forgings are mostly used for important parts with high load and bad working conditions in related machinery except for simple rolled plates, profiles or weldments.