Ferrosilicon - reaction mass of iron and iron disilicide and iron silicide and silicon

Additional physico-chemical information

Administrative data

Endpoint:

other: surface composition

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented publicationlstudy report which meets basic scientific principles

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Analysis was performed by using x‐ray photoelectron spectroscopy (XPS) with a monochromatic Al x‐ray source (150 W) on areas approximately sized 700 x 300 μm. Wide spectra were run to detect elements present in the outermost surface oxide (information depth of a few nanometer) at five different surface area locations. Detailed high resolution spectra (20 eV pass energy) were acquired for the main compositional elements of each test item.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ferrosilicon

EC Number:

912-631-7

Cas Number:

12022-95-6

Molecular formula:

FeSi; FeSi2; Fe2Si

IUPAC Name:

Ferrosilicon

Details on test material:

- Test material identity in study report: ferrosilicon alloys (EINECS n° 234-670-2, CAS n° 12022-95-6; EINECS n° 234-671-8, CAS n° 12022-99-0; EINECS n° --- --- -, CAS n° 8049-17-0). Test material identity given here (EINECS n° 912-631-7) includes these materials.
- Name of test material (as cited in study report): FeSi-std; FeSi-Ba; FeSi-Sr; FeSi-Zr, FeSi-15
- Composition of test material, percentage of components: FeSi-std: Si 75.4% (w/w), Fe 23.8% (w/w); FeSiBa: Si 70.8% (w/w), Fe 22.4% (w/w); FeSiSr: Si 75.9% (w/w), Fe 21.6% (w/w); FeSiZr: Si 69.3% (w/w), Fe 20.0% (w/w); FeSi15: Si 15.0% (w/w), Fe 84.2% (w/w)

Results and discussion

Results:

The surface of each FeSi alloy is composed of silicon and iron rich oxide phases combined with other metal or metalloidal oxides specific for the alloy. These other elements in the surface oxide layer include calcium (FeSi-Ba, FeSi-Zr), barium (FeSi-Ba, FeSi-Zr), strontium (FeSi-Sr), manganese (FeSi-Zr), aluminium (FeSi-std, FeSi-Ba, FeSi-Sr, FeSi-Zr) and tungsten (FeSi-Sr). The thicness of the surface oxide layer is only few nanometers.

Applicant's summary and conclusion

Conclusions:

A thin nanometer thick surface oxide layer composed of silicon and iron rich oxide phases and other metal or metalloidal oxides specific for the alloy is present on the surface of silicon.

Executive summary:

Surface composition analysis of FeSi alloys was performed by using x‐ray photoelectron spectroscopy (XPS). The surface of each FeSi alloy is composed of silicon and iron rich oxide phases combined with other metal or metalloidal oxides specific for the alloy. These other elements in the surface oxide layer include calcium (FeSi-Ba, FeSi-Zr), barium (FeSi-Ba, FeSi-Zr), strontium (FeSi-Sr), manganese (FeSi-Zr), aluminium (FeSi-std, FeSi-Ba, FeSi-Sr, FeSi-Zr) and tungsten (FeSi-Sr). The thickness of the surface oxide layer is only few nanometers.