| 摘要 |
PROBLEM TO BE SOLVED: To provide a formation method of a porous sprayed film capable of heightening by a comparatively-simple thermal spray method, porosity of a porous film used as a heat insulating layer or the like in a combustion chamber or the like of a piston of an internal combustion engine, and to provide an internal combustion engine capable of lowering heat conductivity and a heat capacity of a piston, and improving heat efficiency of the internal combustion engine.SOLUTION: In a production method of a porous sprayed film for forming the porous sprayed film by thermal spray, a thermal spray material is mixed with a water-soluble metal salt and sprayed onto a substrate, and a sprayed film deposited after thermal spray is washed by water to dissolve and remove the metal salt by water, and to thereby form the porous sprayed film on the surface of the substrate.SELECTED DRAWING: Figure 1 |
