An investigation of the structure of amorphous Co-P alloys. 1: X-ray and neutron diffraction

Amorphous Co-P alloys with different phosphorous concentrations were produc ed by melt-spinning, sputtering, and electrodeposition. From the combinatio n of X-ray and neutron diffraction the atomic distances and coordination nu mbers for the Co-Co- and the Co-P correlations were determined. The short r ange structure, in dependence of the P-concentration, 9 at% P less than or equal to c(p) less than or equal to 26 at% P, exhibits rather abrupt change s at the eutectic composition, c(p,e) = 19.9 at% P. It is suggested that at P-contents above c(p,e) the short range order is more pronounced than at l ower P-contents. The coordination of nine Co atoms around P, as established previously for many transition metal-metalloid glasses, is found only at t he eutectic composition. There is almost no dependence of the structure of the amorphous alloys on the specific production method. It is indicated tha t the melt-spun and the sputtered glasses are in a slightly more relaxed st ate than the electrodeposited glasses.