Metal Testing

Chemical Analysis by GDS provides a fast and relatively inexpensive method for analyzing most aluminum, brass, carbon steel, low alloy steel, cast iron, superalloy, and stainless steel materials. XRF Analysis or EDS Analysis can also be used if there is limited sample size or if elements not covered by GDS are required. We sub-contract for inductively coupled plasma (ICP) analysis on samples that don’t work well with our other methods.

Plating composition can be measured using EDS Analysis or XRF Analysis. Jewelry is often plated with 18k gold or platinum which is regulated by the FTC to ensure the correct jewelry composition.

Tensile properties (ASTM E8) provide useful information about the strength and ductility of a metal. Hardness testing is also useful as it can often be correlated with tensile strength and can be done on smaller samples. There are many hardness scales to choose from depending on sample size, uniformity, and industry practice. Brinell Hardness (ASTM E10) uses the largest sample but is useful for materials which are non-uniform such as cast iron. Rockwell Hardness (ASTM E18) has a range of scales covering a large hardness range and uses less material than Brinell Hardness (ASTM E10). Knoop Microhardness and Vickers Microhardness (ASTM E384) testing can be used when little sample is available or a specific area is to be measured. Plating hardness (ASTM B578), and case depth (SAE J423) measurements are examples of microhardness applications.

Our decades of experience and wide range of testing instruments provide a unique advantage for finding the probable root cause of a failure. Scanning Electron Microscopy (SEM) of a fracture surface can often identify the fracture initiation point, mode of propagation, and speed of propagation. A complete picture can be obtained with the addition of EDS Analysis for corrosive elements, microstructural analysis (ASTM E407), base material composition (GDS), mechanical properties, and a service history provided by the client. A detailed report with full documentation of results along with pictures illustrating defective areas is included with every failure analysis project.

Material specifications list specific performance requirements for different grades of metal. Material specifications differ from test methods because test methods only specify how to test for a property but do not include acceptable ranges for the test results. ASTM, SAE, and the military all publish metal certification standards.