SLH Armco Iron: Enabling Precision in Medical Sensor Technology

Medical sensors—used for everything from MRI machines to blood pressure monitors—require extreme precision. Even a tiny error in measurement can have life-threatening consequences, which is why the magnetic cores in these sensors must be made from a material that delivers consistent, reliable performance. SLH Armco Iron has become the gold standard for medical sensor manufacturers, thanks to its ultra-low magnetic loss, high consistency, and biocompatibility.

Medical sensors like MRI gradient coils and pressure transducers rely on magnetic cores to detect or generate precise magnetic fields. Any variation in the core’s magnetic properties can throw off measurements. SLH Armco Iron is made from 99.9% pure iron with carbon content ≤0.01%, which minimizes magnetic loss and ensures uniform performance. At 50Hz (the frequency used in many medical devices), SLH Armco Iron has a magnetic permeability variation of just 3% between batches—far below the industry average of 10%.

A manufacturer of MRI pressure sensors tested SLH Armco Iron against a generic magnetic steel. The SLH-equipped sensors had a measurement error of ±0.08%, compared to ±0.5% for the generic steel sensors. This precision was critical for MRI machines, which need to measure pressure changes in blood vessels with sub-millimeter accuracy. The manufacturer’s sensors now meet the strict ISO 13485 medical device standard, opening up new markets in Europe and Asia.

SLH Armco Iron also offers excellent surface finish, which is essential for micro-sensors. The material is cold-rolled to achieve a surface roughness (Ra) of ≤0.4μm, eliminating burrs or irregularities that could interfere with magnetic field uniformity. The sensor manufacturer reported that they used to spend 2 hours per core polishing burrs; with SLH Armco Iron, they can use the cores straight from the package, cutting production time by 25%.

Biocompatibility is another key requirement for medical devices. SLH Armco Iron is tested for heavy metals (like lead, cadmium, and mercury) in every batch, with all levels kept below 0.0001%. This ensures the material won’t leach toxic substances into the body, even when used in implantable sensors. The manufacturer used SLH Armco Iron in a new implantable pressure sensor for heart patients, which received FDA approval in 2024.

For medical sensor manufacturers, SLH Armco Iron isn’t just a material—it’s a guarantee of quality and safety. In an industry where precision is a matter of life and death, SLH’s commitment to consistency and purity helps manufacturers create devices that healthcare providers can trust. As medical technology advances, SLH Armco Iron will continue to play a vital role in enabling the next generation of life-saving sensors.