Question

Which of the following is not a reason for incomplete fusion?

(a) surfaces to be jointed are coated with oxides

(b) insufficient current supplied by welding equipment

(c) high rate of welding

(d) use of large electrode

I got this question in a national level competition.

This interesting question is from Weld Defects & Types of Joints in division Welded Connections of Design of Steel Structures

Answer 1

The correct option is (d) use of large electrode

To elaborate: Incomplete fusion may result if surfaces to be jointed have not been cleaned properly and are coated with oxides and other foreign materials. Insufficient current supplied by welding equipment and high rate of welding will result in incomplete fusion.