Temperature indicating materials used in welding inspection can take the form of:

• A. Sticks
• B. Pellets
• C. Liquids
• D. All of the above

Answer: (D)

Temperature indicating materials used in welding inspection come in several forms, each providing a visual cue when the surface reaches the target temperature. Sticks (often called temp crayons) are rubbed onto the metal surface and change color as heat approaches or reaches the specified temperature, giving a quick, easy-to-see indication. Pellets are small indicators that can be placed near the weld; they melt or change state/color at a defined temperature, signaling when the target is met. Liquids can be applied as coatings or dyes that react to temperature, showing a color change over a wider area or in hard-to-reach spots. These different formats exist to suit various inspection situations, but all serve the same purpose: confirming the workpiece has reached the required temperature. Therefore, temperature indicating materials can take the form of sticks, pellets, or liquids.