Magnetic tests tell you what a magnet does. Chemical analysis tells you what it is. When a supplier certifies a batch — or a customer rejects one for "wrong composition" — the evidence usually comes from one machine: an ICP-OES analyzer.
What ICP does
A magnet's performance is set by its recipe: how much neodymium, praseodymium, dysprosium, boron, plus small additions like copper, aluminium or niobium. ICP measures exactly that — the amount of each element inside the magnet, down to very small traces. It is how manufacturers prove the recipe was followed, and how buyers verify what they paid for.
How it works, simply
A tiny sample is dissolved in acid, turned into a fine mist, and sprayed into a super-hot plasma — a gas heated to several thousand degrees. The heat makes every element glow, and each element glows with its own signature colour. The brighter the colour, the more of that element is present. Measure the colours, and you know the composition.
What ICP cannot see
ICP measures metals — and that is it. Gases like oxygen, hydrogen, carbon and nitrogen are invisible to it, yet they strongly affect magnet quality. They need a separate test of their own.
Sampling decides the result
The result is only as good as the sample: dirty or corroded parts give wrong numbers, and recycled material varies from lot to lot, which is why standards prescribe exactly how to sample scrap. For buyers, the practical rule is simple — write the critical elements on the drawing, for example "dysprosium 1.5–2.5%", and agree the test method with the supplier before delivery, not after.
Read on: raw material ingredients → · hydrogen and oxygen analysis →