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MACRO SECTION

MACRO SECTION Object: To examine a cross section of a weld for internal defects and soundness. Method:  A transverse section of the weld is cut out. The cross section is then visually inspected. The section is filed down from rough to smooth, then emery or wet/dry papered down to a surface finish of 600 grit. The surface is then etched in NITAL (5% - 10% nitric acid in alcohol), washed off, rinsed and dried. (Possibly a final clean with acetone and mount in Bakelite) The specimen is then inspected at up to 10-x magnification. Reporting Results: Material. Welding process. Specimen identification. Sentencing standard. Thickness. Geometric flaws - type, size and location. Internal flaws - type, size and location. Parent metal flaws - type, size and location. Accept or reject, to standard, for each flaw.    Comparison of macro section and micro section:                                                                         MACRO                                   
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'NICK' BREAK (BEND) TEST

'NICK' BREAK (BEND) TEST Object :  As for fillet weld fracture, used on butt welds. Method: The specimen is cut transversely to the weld, and a saw cut is applied along the center of the weld face. The best place for the cut is at a start I stop. The specimen is fractured by bending or by hammer blows. The nick bend test will find internal defects. Reporting Results: Thickness of material.  Width of specimen.  Location of fracture.  Appearance of joint after fracture.