Destructive Testing Lab Services
WTTI performs the following Destructive Testing Lab Services in our accredited laboratory:
- Guided Bend Specimens
- Fillet Weld Fracture Testing
- Transverse Tensile Testing
- All Weld Metal Tensile Testing
- Hardness Testing
- Macro Etching
- Micro Examiniation
- Sectioning, Mounting and Polishing
Guided Bend Specimens
Guided bend tests are used to determine the quality of the welded joint, as well as the degree of penetration and fusion to the base metal.
Fillet Weld Fracture Testing
Fillet weld fracture testing is done by breaking the welded joint with force and then visually inspecting the fractured area to determine weld penetration and quality.
Transverse Tensile Testing
Tensile strength is defined as stress in pounds per square inch. The transverse strength of groove welds is measured by applying tensile stress on the test specimens to calculate the ultimate strength of a welded joint.
All Weld Metal Tensile Testing
In an all weld metal tensile test, the specimen is prepared from all weld metal. This type of specimen is prepared by machining a groove in a plate of steel and then completely filling the groove with deposited weld metal. The surrounding steel is then machined away leaving a specimen of weld metal.
The purpose of such testing is to test welding filler metal mechanical properties for their suitability for the job concerned and/or the quality of deposited metal in welded joint.
- Brinell: The Brinell test is frequently done on large parts and are used to determine the hardness of forgings and castings that have a grain structure too course for Rockwell or Vickers testing.
- Rockwell: The Rockwell hardness test method consists of indenting the test material with a diamond cone or hardened steel ball indenter. The advantage is the rapid testing time on hard materials.
- Vickers - Microhardness: Vickers Microhardness testing of metals, ceramics, and composites is useful for a variety of applications such as testing very thin materials like foils, measuring individual microstructures within a larger matrix, or measuring the hardness gradients of a part along the cross section.
Macro Etching examination gives a broad picture of the specimen by studying relatively large sectioned areas. Macro examination reveals cracks, slag inclusion, blowholes, shrinkage porosity, weld penetration, and the boundary between the weld metal and the base metal by removing small samples of the welded joint.
Micro Etch examination involves areas much smaller than those considered in macro etch examination. Micro examination determines cracks and inclusions of microscopic size, grain boundaries and solidification structures of weld metal, heat affected zone and the base metal, distribution of micro constituents in the weld metal and the quality of heat treatment in a welded specimen.
Sectioning, Mounting, and Polishing
Sectioning, mounting and polishing are performed in conjunction with one another to hold small parts for cross section etching and examination. This allows for evaluation of very small parts that would otherwise be inaccessible to destructive examination.