Method of manufacturing transition piece and transition piece

A method of manufacturing a transition piece, comprising:

• laminating a base material powder on a base and simultaneously irradiating the base material powder with a laser beam to form a layer of one end having the same composition as one material to be welded;
• determining whether a dimension of the formed layer of the one end or time required for the formation reaches a preset set value;
• upon determining the dimension of the formed layer of the one end or the time required for formation does not reach a preset set value, forming another layer on the layer of the one end with the base material powder;
• upon determining the dimension of the formed layer of the one end or the time required for formation reaches a preset set value, laminating a metal powder on the one end and simultaneously irradiating the metal powder with the laser beam to form a layer of an intermediate layer;
• determining whether a composition of the layer of the intermediate layer meets a predetermined value;
• upon determining the composition of the layer of the intermediate layer does not meet the predetermined value, forming another layer on the layer of the intermediate layer using the metal powder;
• upon determining the composition of the intermediate layer meets the predetermined value, laminating a mating material powder on the intermediate layer and simultaneously irradiating the mating material powder with the laser beam form a layer of another end;
• and
• determining whether a dimension of the formed layer of the another end or time required for the formation reaches a preset set value,
• wherein the another end has the same composition as another material to be welded,
• wherein the composition of the one end and the composition of the another end becomes the same as approaching a center of the intermediate layer,
• wherein at least the intermediate layer among the one end, the other end, and the intermediate layer is formed by an additive manufacturing method, and
• wherein a first piece material having the same composition is used as the one material to be welded as the one end, a second piece material having the same composition is used as the other material to be welded as the another end.