Destructive testing (DT) is an essential process in the materials selection and approval process for high-performing materials.
DT is often performed on low-cost, high-volume components. In opposition to non-destructive testing (NDT), in which inspections are performed with no material damage to the asset’s structural integrity, destructive tests stretch, bend, fracture, and otherwise strain the component until mechanical failure in a controlled environment.
This is done to gauge, among other factors, their strength, hardness, stiffness, and the amount of damage they can sustain while in operation, all according to customer specifications. Destructive testing is designed to produce consistent, repeatable results, so if one component fails a certain way, it can be expected that others that were manufactured with a similar process will have similar flaws.
DT is necessary for composites, metals, and other materials that are used in airplanes, cars, storage tanks, and many other applications often have to perform under extreme stress and high temperatures.
MISTRAS’ destructive testing services mimic these environments to test component specimen until mechanical failure, to ensure they will perform safely once in operation. MISTRAS’ DT services can be utilized for a variety of materials including:
Metals, specimens, and composites can be subjected to increasing levels of tension, compression, shear, and peeling during their normal operations. MISTRAS uses a variety of mechanical testing techniques in which adding temperature, strain, unidirectional load, or shear load can provide useful results about how these components will respond when operating under extremes stress. Some of MISTRAS’ mechanical tests are below.
MISTRAS uses applied force destructive testing to ensure the quality and fit-for-purpose of spot welds and other equipment componentry. Force is externally applied to the asset to break away the material and reveal the weld zone for further inspection and analysis. This form of testing allows technicians to get a more in-depth inspection of the asset to assess the level and extent by which external forces affect the component being tested.
MISTRAS uses bend tests to provide a simple and straightforward way of evaluating the quality of materials based on their ability to resist cracking and other faults during a continuous bend. It is often used for quality control testing of butt-welded joints.
A relatively simple test to perform and analyze, bend test results offer insights as to how a material will react to pressure, along with its likelihood to experience failure under stress.
Hardness testing is extremely useful in the selection of materials, because it gives an indication of how the material is affected by stress and how it will wear over time. The results of this test can be used to direct quality control and acceptance of components, along with providing data regarding the structural integrity and material composition of an asset.
MISTRAS offers several different types of hardness tests which can be applied to a variety of materials and equipment, including castings, forgings, and other metal materials, along with surface coatings and treatments. MISTRAS utilizes the following HT techniques:
For welded materials, impact testing can be used to provide information about the strengths and behavior properties of the weld. The test itself is performed at a variety of temperatures to replicate the environment of the material when it is used in service.
Analysis of a material’s microstructure in order to determine chemical composition and technological properties. Offers insight into determining failure mechanisms and asset lifespan expectations.
In Nick Break testing, a sample is cut from a welded butt joint to split the component in two. Each surface area is then analyzed to ensure that any present internal defects – such as inclusions, incomplete penetration, or porosity – are within established discontinuity limits.
Forced are applied parallel to the contact surface to determine strength, durability, and other properties under extreme shear stress, which is stress being applied along a parallel plane. This differs from tension testing, in which forces are applied perpendicular to the contact surface. This type of testing is important for components like bolts or screws, which experience shear forces if the surfaces that they are fastening together move side-to-side.
MISTRAS technicians apply controlled tension to metallic and polymer materials until failure, with the objective of gauging its ultimate tensile strength, maximum elongation, yield strength, elasticity, ductility, stiffness, and other material characteristics. Also called a ‘tension test’, the test can be performed under a variety of conditions, tailored specifically to each experiment depending on the environment of the material being observed.
Tensile testing is often performed on castings, welds, wires, and rebar and tubular products.
Questions? Speak to our Destructive Testing experts today.Contact a MISTRAS expert