| 摘要 |
PURPOSE:To prevent piston seizure and the like by a method wherein a cylinder liner made of graphite dispersed cast aluminum alloy having the same linear expansion coefficient as that of the parent metal is wraptly cast into the parent metal of the cylinder block made of aluminum alloy casting. CONSTITUTION:When the cylinder linear made of graphite dispersed cast aluminum alloy containing 5-20vol% of graphite in the aluminum alloy casting having the same linear expansion coefficient as that of the parent metal is inserted in the parent metal of the cylinder block made of aluminum alloy casting, the cylinder contracts at almost the same rate as that of volume contraction of the parent metal of the cylinder block produced during the process of state change from molten metal state of aluminum, through its solidified state, to its cooling state, without producing any residual stress around the cylinder liner. Consequently, duing the operation, no cylinder deformation due to the release of the residual stress at the temperature rise is resulted. Furthermore, the cylinder liner made of aluminum has a better thermal conductivity than that made of cast iron, resulting also in contributing to the cooling ability of the engine. |
