設計・制御
Firing Program A–H Stages
Japanese: 焼成プログラム8段階（A–H）
An eight-stage standard fusing firing program, ranging from initial heating (A) to cooling to room temperature (H). This was first clearly defined by Rei Chikooka (2012).
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The 8-stage firing program (A–H) is a system that organizes the standard fusing firing schedule into eight stages. Rei Chikaoka (2012, p. 95) was the first to explicitly define this system, which consists of eight steps: A (initial heating), B (temperature equalization), C (rapid heating), D (holding at peak temperature), E (rapid cooling), F (holding at slow-cooling temperature), G (slow cooling), and H (cooling to room temperature). This corresponds to the η-T-t trajectory notation (heat-up/soak/squeeze/peak/crash/anneal/cool) used in this paper.
The meanings and primary physical processes of each stage are as follows: A (Initial Heating): Temperature is raised at a rate governed by heat conduction to avoid thermal shock. B (Temperature Equalization): The internal and external temperatures of the shelf and glass are equalized at around 500°C. C (Rapid Heating): This stage is passed through quickly to prevent devitrification. D (Peak Temperature Hold): Shape is determined by viscous flow. E (Rapid Cooling): Pass through the decolorization range of 600–750°C in the shortest possible time (crash cooling). F (Slow Cooling at a Constant Temperature): Eliminate permanent strain at 482°C (Adams-Williamson rule). G (Slow Cooling): Cool slowly at a rate of 80°C/h until below the strain point. H (Cooling to Room Temperature): Cool to room temperature via natural cooling.
Related Concepts
Gain a comprehensive understanding of firing design by considering rapid cooling (crash-cool), bubble squeeze (bubble-squeeze), the η-T-t framework (eta-t-t-framework), and the joint design rule (joint-design-rule) together.
This entry is written in Japanese by Rei Chikaoka and translated for readers outside Japan. If something reads oddly, the original is the source of truth.