The invention discloses a bent hole inner surface
polishing and strengthening treatment device and method. External controllable square planar magnetic fields are placed on the front side, the rear side, the left side and the right side of a to-be-ground workpiece with a bent hole, and an external controllable annular
magnetic field surrounds the periphery of the to-be-ground workpiece with the bent hole as the center; the soft magnetic
grinding head is formed by detachably connecting
multiple stages of
grinding heads in series front and back through rotary connecting pieces, the innermost part of each stage of
grinding head is provided with an air bag, the outer surface of the air bag is tightly attached to an internal framework, the outer surface of the internal framework is tightly attached to a magnetic carrier layer, and an
abrasive particle layer is embedded in the outer surface of the magnetic carrier layer. The particles of the
abrasive particles on the front-stage grinding head are larger than the particles of the
abrasive particles on the rear-stage grinding head; active bending of the grinding head in the stretching-in process and expansion from inside to outside in the
grinding process are achieved, rough grinding, accurate grinding and
polishing are conducted from front to back, the grinding state is maintained through inflation, the abrasive particle layer is separated from the hole wall through deflation, and controllable adjustment of the grinding area is achieved.