Using a halogen point heater, we locally heated a stainless-steel plate and observed temper colors (thermal coloring) and thermal deformation.
As the plate’s center was heated, vivid temper colors such as blue, purple, and gold appeared, and the center area expanded. This thermal expansion created internal stress, clearly causing the four corners of the square plate to warp upward.
This video visualizes how localized infrared heating affects the color changes and structural deformation of metal surfaces.
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