Macro sectioning in destructive testing involves which procedure?

Macro sectioning in destructive testing involves which procedure?

• A. Using non-destructive surface imaging.
• B. Observing the surface for defects.
• C. Polishing and etching a small section of welded material.
• D. Measuring electrical conductivity.

Answer: (C)

Macro sectioning in destructive testing is about exposing a cross-section of a welded joint so you can inspect its internal features at a macroscopic level. The procedure involves taking a small section of the welded material, cutting it to reveal the cross-section, then polishing the surface to a smooth finish and applying an etchant. The etchant highlights the weld bead, heat-affected zone, and grain structure, making these features visible to the eye or with low-power magnification. Because material is cut away to create that cross-section, this is a destructive test. The other options describe non-destructive surface checks or tests that don’t reveal the internal cross-section, so they don’t fit macro sectioning.

Macro sectioning in destructive testing is about exposing a cross-section of a welded joint so you can inspect its internal features at a macroscopic level. The procedure involves taking a small section of the welded material, cutting it to reveal the cross-section, then polishing the surface to a smooth finish and applying an etchant. The etchant highlights the weld bead, heat-affected zone, and grain structure, making these features visible to the eye or with low-power magnification. Because material is cut away to create that cross-section, this is a destructive test. The other options describe non-destructive surface checks or tests that don’t reveal the internal cross-section, so they don’t fit macro sectioning.