The method includes a step of preparing a first member made of a first metal and a second member made of a second metal having a smaller deformation resistance than the first metal, and a step of joining the first member and the second member. The step of joining includes a step of disposing the second member in a cavity of a mold, a step of heating the first member and the second member by relatively rotating the first member with respect to the second member, while pressing the first member against the second member, without changing a positional relationship, and a step of cooling the first member and the second member with the members being in contact with each other. In the step of disposing, the second member is disposed such that a second member contact surface is surrounded by the sidewall of the cavity.