What is the difference between PMI and Chemical Analysis?


When faced with a decision to choose between PMI or Chemical Analysis to determine the chemistry of a sample, how do both methods stack up against each other? This article will explain the main differences between them and explore the advantages and disadvantages of both.

Positive Material Identification (otherwise known as PMI) is a rapid, non-destructive method of verifying the chemical composition of a metal or alloy. As a highly portable tool, it offers the quickest and most cost-effective solution to determining the chemical composition of a component or batch material. Its applications are wide ranging from being able to quickly identify large batches of finished product to re-certifying materials. Different techniques such as X-Ray fluorescence (XRF) allow a fast identification of the key elements whereas Optical Emission Spectroscopy (OES) can analyse for carbon and lighter elements.

Chemical Analysis is a more time-consuming and complex solution to determining a materials chemical composition. The versatility of chemical analysis means it can be used in a wide variety of industries such as biological, metallurgical, and chemical uses. For example, ICP-OES (Inductively Coupled Plasma Optical Emission Spectroscopy) involves a trace level analytical technique by introducing a plasma beam to the surface of the material which in turn emits a spectrum of emission lines that characterise each element within the sample.

To choose the right solution, it is important to weigh the pros and cons for each method as highlighted below.

The main advantages and disadvantages of PMI are:

The main advantages and disadvantages of Chemical Analysis are:

In conclusion, both methods offer a unique solution for material identification, depending on the applications and cost considerations.

For more information regarding these two methods that ASAMS is happy to subcontract to its long-standing suppliers, contact the team at This email address is being protected from spambots. You need JavaScript enabled to view it. or call 01493653535 for quotations and further details.