Macro examination: Etched or non-etched test specimen surface is examined with naked eyes or optical instruments (magnifying glass, stereo microscope etc.) with a small magnification (<x20). Cracks, pores, debris, penetration, heat affected zone (HAZ), welding passes, etc. can be determined.
Micro–Examination: Etched or non-etched test specimen surface is examined with a larger magnification (> x20) using metallography microscopes. Micro-structure determination, grain size, grain orientation, phase sedimentation etc. can be determined.
Standards:
TS 3849 ISO 4969: Steels-Macroscopic examination by etching with strong mineral acids
TS EN ISO 17639: Destructive tests on welds in metallic materials – Macroscopic and microscopic examination of welds
TSE CEN ISO/TR 16060: Destructive tests on welds in metallic materials – Etchants for macroscopic and microscopic examination
TS EN 2715: Aerospace series – Macrographic examination of aluminium and aluminium alloy wrought products, forging stock and forgings
TS EN 2954-002: Aerospace series – Macrostructure of titanium and titanium alloy wrought products – Part 001: General requirements