'Combine series', which has the meaning of combining and binding, looks similar, but like water and oil, which cannot mix, within the physical properties of metal, there are different properties that cannot be mixed, such as ferrous metal and non-ferrous metal. This is a work that interprets the process of combining metals with each other. It was manufactured using a welding method that combines brazing and welding by matching dark ferrous metals with non-ferrous metals with unique colors such as red copper and brass. The 'Combine series' focused on understanding the essence of materials and used a minimal formative language that did not interfere with it, realizing three-dimensionality through the combination of different metals as a means of expressing the beauty latent in the materials. .