Q: Can the finished vacuum insulated glass (VIG) unit undergo the Heat Soak Test (HST)? What is the reasoning behind this?

A: No, it cannot. The heat soak process typically occurs at temperatures around 290°C (the phase transformation temperature of nickel sulfide). This exceeds the melting point of the low-temperature metallic sealing material used in our vacuum glass, causing the seal to fail and leading to vacuum loss.
Note: However, the individual glass panes can undergo heat soak independently before being assembled into a vacuum-insulated unit.