Comparing the deflection of different colored glass strips

Abstract

Glass is a material that has been used for both practical and artistic purposes starting as early as the 1st century BC, and the stiffness of the glass affects how easy the glass is to work with. A three-point bending test was performed at 582°C (1080°F) for strips of transparent red, clear, black, transparent blue, and white glass. The deflection of the center point of each strip of glass was measured as the temperature was held constant. A proportional relationship of deflection with time was found for the red and white glass and the deflection of the clear, black, and blue glass was characterized by a parabolic relation. It was found that the red glass is the least stiff, followed by black, blue and clear, which have no statistically significant difference in stiffness, and finally the white glass was found to be the most stiff. These were contrary to the glass workers expectations, which was that black would be the least stiff. This will help glass workers know which colors will act similarly, and what to expect of different colors of glass.