Alloy libraries for handheld XRF analyzers: which ones are available and how to work with them
Nowadays a huge number of different alloys are widely used in various industries, the performance characteristics of products made from them depend on their quality. Therefore, analysis of metals and alloys, as well as their conformity to certain standards, is one of the main tasks of quality control in production. The XRF method is excellent for solving this task because it is non-destructive and allows a large number of samples to be analyzed quickly and reliably. One of the reasons for the popularity of this method is that modern portable XRF analyzers are capable of quantifying the elemental composition in less than a minute, and the built-in alloy libraries make it possible to immediately check whether the measured composition corresponds to any standard.
Alloys libraries are extensive databases that contain information about the chemical composition of alloys, as well as permissible deviations from the standard. International alloy grade libraries such as GOST, AISI, DIN, or UNS are usually used, but custom ones can also be configured. Standard libraries are usually present in the analyzer’s memory at the time of purchase, but custom or missing libraries can also be installed if needed. Custom libraries are created by the instrument operator and may include sets of standards used in a specific enterprise. Thus, they may contain unique alloy grades not present in standard libraries or a limited number of grades used in a specific production process.
There are several modes of operation for alloys libraries in Elvatech handheld XRF analyzers. The main difference between them is how quickly and in what form the analysis results are required.
Alloy Matching Mode
The easiest way to work with alloy grades is the alloy grade matching mode (PASS/FAIL mode). In this mode, the user selects the alloy grade of interest, the matching threshold, and after a measurement, the instrument automatically determines whether the measured alloy matches the given standard. This is very useful for quality control of incoming raw materials because it takes only seconds to measure, allowing large numbers of samples to be checked quickly. The advantage of this method is that the user can set a matching threshold value at which the analyzed sample meets his requirements. This allows you to sort out similar alloy grades with only slight variations in chemical composition.
Alloy Comparison Mode
One alternative way of working with alloy libraries is by comparing with the alloy being measured. To do this, the spectrometer compares the composition obtained during measurement with the composition of a standard alloy available in the library. This can be either an international standard or a custom standard that was manually added to the instrument’s memory by the user. This makes it possible not only to check whether the alloy corresponds to the standard norms, but also to determine how significantly or insignificantly its composition differs from the required one and by which chemical elements.
When an unknown sample is measured, the instrument is able to find the most appropriate alloy grade corresponding to the measured composition. This makes it possible to quickly identify any standard alloy. However, sometimes several grades may differ only in elements that cannot be detected with the XRF method, especially for steels, since carbon is not detected with the XRF method. In this case, the user will be provided with a list of grades that satisfy the measured concentrations of the elements detected.
Thus, portable XRF analyzers are versatile tools for analyzing the elemental composition of materials. They also provide the operator with quick access to standards libraries and the ability to edit them by creating custom sets of standards. Alloy libraries allow users to quickly and reliably verify that a specific part or component of interest meets any established standard, international or custom, or to identify the grade of a standard alloy if it is not known.