Effects of vacuum smelting-casting on the composition

microstructure and properties of the Cu-Cr-Zr-Mg alloy have been investigated to optimize the vacuum smelting-casting process

such as processing parameters

pre-treatment of cast mould. The results indicate that smelting temperature for the alloy should be controlled below 1 480 ℃

or else the alloy melt would react with the crucible matrix to result in the introduction of elements in crucible into the alloy. The burning-loss rate of elements in the alloy can be greatly decreased and the alloy composition can be accurately controlled by the vacuum smelting process. In addition

if pouring temperature is higher than 1 400 ℃

some defects

such as density-reduction

gas hole increase

coarse grain

segregation of the dendrite

deep porosity hole

are easily formed in the alloys.