Burn-through occurs due to what condition?

Burn-through occurs due to what condition?

• A. A decorative pattern of the weld
• B. Melt-through of base metal from excessive heat or poor joint design
• C. The deposition of metal
• D. A chemical reaction

Answer: (B)

Burn-through happens when the heat from welding is more than the base metal can safely absorb for its thickness and the way the joint is designed. The weld pool and heat input melt through the base metal, creating a hole from one side to the other. This is typically caused by excessive heat input (for example, too high current or too slow a travel speed) or a joint design that concentrates heat or leaves insufficient thickness at the weld area. It’s not about depositing extra metal, creating a decorative pattern, or a chemical reaction—the base metal itself is melted away through the thickness. To prevent it, control heat input, ensure proper joint design and fit-up, and adjust travel speed and technique as needed.

Burn-through happens when the heat from welding is more than the base metal can safely absorb for its thickness and the way the joint is designed. The weld pool and heat input melt through the base metal, creating a hole from one side to the other. This is typically caused by excessive heat input (for example, too high current or too slow a travel speed) or a joint design that concentrates heat or leaves insufficient thickness at the weld area. It’s not about depositing extra metal, creating a decorative pattern, or a chemical reaction—the base metal itself is melted away through the thickness. To prevent it, control heat input, ensure proper joint design and fit-up, and adjust travel speed and technique as needed.