Metal testing is a process or procedure used to check composition of an unknown
metal
A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typi ...
lic substance. There are destructive processes and nondestructive processes. Metal testing can also include, determining the properties of newly forged
metal alloys. With many
chemical-property databases readily available, identification of unmarked pure, common metals can be a quick and easy process. Leaving the original sample in complete, re-usable condition. This type of testing is nondestructive. When working with alloys (forged mixtures) of metals however, to determine the exact composition, could result in the original sample being separated into its starting materials, then measured and calculated. After the components are known they can be looked up and matched to known alloys. The original sample would be destroyed in the process. This type of testing is destructive.
Destructive testing (DT)
In this kind of testing, the material undergoes mechanical testing and is discarded thereafter. Test results are compared with specifications. Subtypes include:
* Bend test
* Impact test – Further categorised as
Charpy test
In materials science, the Charpy impact test, also known as the Charpy V-notch test, is a standardized high strain rate test which determines the amount of energy absorbed by a material during fracture. Absorbed energy is a measure of the mater ...
and
Izod test
The Izod impact strength test is an ASTM standard method of determining the impact resistance of materials. A pivoting arm is raised to a specific height (constant potential energy) and then released. The arm swings down hitting a notched sample ...
* Hardness test
*
Tensile test
* Fatigue test
* Corrosion resistance test
* Wear test
Nondestructive testing (NDT)
Raw and finished material undergoes testing according to code specifications such as
ASME
The American Society of Mechanical Engineers (ASME) is an American professional association that, in its own words, "promotes the art, science, and practice of multidisciplinary engineering and allied sciences around the globe" via " continuing ...
Boiler and Pressure Vessel Code Section V. The tested material is not damaged by the test. Subtypes include:
* Visual testing
*
Dye penetrant inspection
*
Magnetic particle inspection
*
Radiographic testing
*
Ultrasonic testing
Ultrasonic testing (UT) is a family of non-destructive testing techniques based on the propagation of ultrasonic waves in the object or material tested. In most common UT applications, very short ultrasonic pulse-waves with center frequencies ...
* Leak testing
* Eddy current testing
* Remote field electromagnetic testing
* LR UT
See also
*
Metallurgical assay
A metallurgical assay is a compositional analysis of an ore, metal, or alloy, usually performed in order to test for purity or quality.
Some assay methods are suitable for raw materials; others are more appropriate for finished goods. Raw pre ...
References
Metalworking
{{science-stub