The crystallization characteristics of copper alloys of various compositions are different, the casting properties are different, and the casting process characteristics are also different.
1. Tin bronze: The crystallization characteristic is a large crystallization temperature range and a wide solidification area. In terms of casting performance, the fluidity is poor, shrinkage is easy to occur, and it is not easy to oxidize. The characteristic of the process is that the thick-walled parts adopt directional solidification (sequential solidification), and the complex thin-walled parts and general thick-walled parts adopt simultaneous solidification.
2. Aluminum bronze and aluminum brass: The crystallization characteristic is that the crystallization temperature range is small, and it is the characteristic of solidification layer by layer. In terms of casting performance, fluidity is good, concentrated shrinkage is easy to form, and it is easy to oxidize. The process feature is that the aluminum bronze pouring system is bottom injection type, and the aluminum brass pouring system is open type.
3. Silicon brass: The crystalline characteristic is between tin bronze and aluminum bronze. The best casting performance (in special brass). The process is characterized by sequential solidification process, mid-injection gating system, and small size of the dark riser