2018 - Understanding Gold Alloy Features from Thermodynamic Phenomena
2018 - Understanding Gold Alloy Features from Thermodynamic Phenomena
The production success of lost-wax casting depends not only on the process parameters of the casting systems but also on the chemical composition of the alloy, which strongly affects its behavior in the liquid state. In addition, potential solid-state phase transitions alter the alloy’s mechanical properties. The characteristics of the alloy in its liquid state and its density changes due to solidification can affect the form-filling capabilities and the quality of the pieces.
The aim of this research is a deeper understanding of the relationships between the chemical composition, the main thermodynamic characteristics, and the castability of an alloy in investment casting in order to create an instrument capable of predicting its technological behavior in advance, thus avoiding the expensive process of characterization. The analysis of the relationship between alloy composition and castability was carried out by means of traditional investment casting and by using Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TG) and Dilatometry (DIL), using the simplest binary alloys up to the more complex formulation of some gold alloys suitable for jewelry making.
Author: Stefano Rappo