Patent attributes
An object is to reduce loss of exhaust gas by improving a surface roughness to enhance efficiency of a turbocharger and to reduce generation of a crack due to thermal fatigue to improve durability, as well as to ensure rigidity to prevent exhaust-gas leakage to outside. A turbine housing accommodates a turbine wheel rotated by exhaust gas taken in from an engine and includes a scroll part having a scroll shape and forming, on a radially-inner side, an exhaust-gas flow passage. The turbine housing includes: a casted exterior member forming an opening portion accommodating a back-face member attachable and detachable in an axial direction of the turbine wheel; and a sheet-metal interior member disposed inside the exterior member via a predetermined clearance part from the exterior member and forming the scroll part. The interior member is configured to be attachable and detachable with respect to the exterior member through the opening portion.
