| 摘要 |
PROBLEM TO BE SOLVED: To easily obtain a cylinder head having stable and high joined strength in a short time while unnecessitating severe control of the joining condition, in the case of joining each valve seat with an opened peripheral ridge part of each port in the cylinder head body. SOLUTION: A brazing filler metal layer 7 is pre-formed on the joining surface part of the valve seat 3 through iron-side fused reacting layer 5 as a diffusion layer of a brazing filler metal (Zn-Al eutectic alloy) having lower m.p. than these of both of the cylinder head body 2 and the valve seat 3 and composed of the eutectic composition with the cylinder head body 2 (Al) and the valve seat 3. The liquid phase diffusion-joining of these valve seat 3 and cylinder head body 2, are executed through both fused reacting layers 5, 6 while forming the aluminum side fused reacting layer 6 as the diffusion layer between the brazing filler metal and the cylinder head body 2 so that the m.p. of the brazing filler metal is made high and discharging the molten brazing filler metal from the gap between the joining surface parts of both members 2, 3 by generating the heat and pressurizing according to the conduction of electricity between both members 2, 3. |
