PURITY OF STEEL AND ALUMINUM

Fast automated SEM-EDX analysis of non-metallic inclusions

Non-metallic inclusions

Production of steel & aluminium

Non-metallic inclusions are microscopically small deposits in steels and other metals (particularly aluminum), which often consist of oxides or sulfides. Inclusions are deliberately introduced to adjust certain material properties or they arise as impurities during the manufacturing process. Non-metallic inclusions cause a localized interruption of the structure. They therefore have a negative impact on the strength properties. 

Purity of steel

The purity can be determined relatively easily by optically counting the inclusions in the micrograph (DIN EN 10247, ASTM E45, JIS G 0555, ISO 4967). To do this, a lollipop sample is taken from the melt and prepared using a rapid method.

For the detailed analysis of non-metallic inclusions, SEM-EDX systems with automatic particle analysis are particularly suitable, allowing precise characterization of the number, size, shape and chemistry of the inclusions (ASTM E2142).

Inclusions lead to failure

Catastrophic material defects, such as fatigue fractures or delamination cracks, often arise from larger inclusions.

Additives in steel production

During steel production, additives are also added to the melt. Aluminium and silicon are added to bind and remove oxygen (“deoxidation”), and calcium is used to remove sulphur. Residues of the additives remain in the melt as unwanted inclusions. Other additives are used to specifically improve properties such as strength or corrosion resistance. Manganese sulphide, for example, significantly improves the machinability of steels.

Clogging of the pouring pipe ("Nozzle Clogging")

A well-known problem in steel production is the clogging of the pouring tube due to the gradual accumulation of oxide inclusions. By controlling the oxide inclusions in the melt, this mechanism can be prevented and expensive downtimes are minimized.

Phenom ParticleX

One system, two areas of application

The ParticleX combines two application areas of SEM-EDX analysis in one device. Beam generation with a CeB6 cathode ensures excellent brilliance and resolution. Magnifications of over 50k times are achievable even for beginners. This makes the analysis of defects and fractures in metals (fractography) child's play.

On the other hand, the Phenom ParticleX is equipped with the powerful Perception software for particle analysis and a reporting system specifically for non-metallic inclusions.

Special sample recordings

Meaningful reporting

The Perception Reporter automatically creates reports, the template can be freely configured according to customer requirements. Image galleries, ternary diagrams, histograms and much more are available.