| 摘要 |
PURPOSE:To bond a plating layer and an underlying alloy firmly and improve the heat conductivity and durability of a deposition hardening type copper alloy mold by subjecting the plating layer on the inside surface of said mold to solubilizing treatment and deposition aging heat treatment under specific conditions of temps. and time. CONSTITUTION:Plating of Ni, Ni-Fe, Ni-Co, or Ni-Mn is carried out on the inside surface of a copper alloy mold. Next, it is subjected to solubilizing treatment under conditions of 930-960 deg.C and 0.75-2hr, and after quick cooling, it is subjected to deposition aging heat treatment of 3-4hr at around 400 deg.C. By this treatment, the plating layer is firmly bonded to the underlying copper alloy. The reason for specifying the temp. and time lies in that if it is exposed to high temps. for an excessively long time the crystal grains of the copper alloy coarsen and this results in decreased strength. With the low temp. and short time, the removal of the oxide films or pores formed in the melt-sprayed film is not sufficiently carried out. |
