Flow channel forming plate, blade and gas turbine including this, and method of manufacturing flow channel forming plate

Abstract

A flow channel forming plate has a gas path surface which comes into contact with combustion gas, an opposite gas path surface which faces a side opposite to the gas path surface, an end surface formed at a circumferential edge on the gas path surface, and a lateral passage formed between the gas path surface and the opposite gas path surface and in which cooling air flows. The end surface has a rear end surface, a front end surface, and a lateral end surface. The lateral passage has, along the gas path surface and the lateral end surface, a main passage portion extending in a direction in which the lateral end surface extends, and one or more narrow passage portions extending from an end of the main passage portion on a downstream side toward the rear end surface and opening on the rear end surface.