This technical brief from Jiangsu Aokai analyzes how excessively low or high sintering temperatures damage PTFE high-temperature cloth. Low sintering leaves particles unmelted, causing micro-pores, weak coating-substrate bonding, rough surfaces, poor mechanical strength, and milky opaque appearance. Overheating induces PTFE thermal degradation, generating pinholes, bubbles, brittleness, yellow-to-black discoloration, and releasing toxic fumes. Both extremes destroy compactness, non-stick performance, flexibility, insulation, and dimensional stability.