| 摘要 |
PURPOSE:To improve heat resistance and to prevent the occurrence of a weld loss and a crack even when a complicated combustion chamber shape is employed by forming a whole or a combustion chamber part of a low expansion alloy of a specified composition. CONSTITUTION:A whole or a combustion chamber part 1 is formed of a low expansion alloy. The low expansion alloy has a composition consisting of 0.8-3.0wt.% C, 0.8-3.0wt.% Si, 2wt.% or less Mn, 30-34wt.% Ni, 4-6wt.% Co, 0.02-0.08wt.% Mg or Ca, and a rest part of Fe containing impurity, and a piston for an internal combustion engine has the composition. By utilizing low expansion characteristics, the outside diameter of the piston is designed so that a clearance between said outside diameter and the inside diameter of a cylinder liner can be minimized. |
