Industrial Applications Materials & Components

Composition of stainless steel bolts assessed using neutrons

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Bumax is a Swedish manufacturer of premium-brand high strength stainless steel fasteners, designed for extreme environments. A number of different materials are used to produce A4-grade stainless steel, including Bumax-88.

The challenge

Bumax was looking to enhance its quality assurance programme with extremely precise measurement techniques that could be used to benchmark their methods for assessing the elemental composition of the raw materials required for the manufacture of Bumax-88.

The experiment

Bumax was advised on the advantages of Neutron Activation Analysis (NAA), which is a technique that uses nuclear processes to determine multi-element concentrations.While extreme forces were applied to the sample, changes in the alloy were studied using neutrons. In addition, neutrons were used to study the structure of the sample before and after loading to identify pores and cracks.

The results

The concentrations of manganese, nickel, molybdenum, cobalt and copper could be quickly determined for each sample. Measurements revealed that the composition of Bumax-88 is significantly different from the standard material A4-grade material tested for comparison.

The analysis performed by the people at Delft is really great and shows that Neutron Activation Analysis technology can help us with particularly precise characterisation of our products.

Camille Feuillet

Field Application Engineer,
BUMAX France