Electron microscopy study of chemically deposited Ni-P films

Abstract

The structure ofele~troless thin films of NiP has been studied. The microstructare and the selected area diffraction pattern of the samples reveal that certain samples transform to crystalline Ni with P in solid solution by nucleation and growth, whereas others transform to crystalline state by growth alone. The former set of thin films having a P-content of 19-21 at. To is character~ed as amorphous. Films with a P-content of 13-15 at. ~o fall in the latler category and are characterized as microcrystalline. Those with a P-content of 16-18 at ~/o contain both amorphous and microcrystalline regions.

Surface characterization of zincated aluminium and selected alloys at the early stage of the autocatalytic electroless nickel immersion process

“…On the other hand, high phosphorus deposits seemed continuous and amorphous. Kreye et al [8] and Zhang et al [9] described electroless nickel coatings with very low phosphorus content as equiaxed and nanocrystalline, while Yamasaki et al [10], Tyagi et al [11] and Hur et al [12], concluded that low phosphorus deposits are crystalline, containing a supersaturated solid solution of phosphorus in the nickel lattice. X-ray diffraction patterns obtained from electroless nickel deposits are known to change with heat treatment as it involves change in microstructure of the nickel matrix [13].…”

Strategy to Improve the High-Temperature Mechanical Properties of Cr-Alloy Coatings

“…Additionally, the hardness level attained after annealing at these temperatures (~13.0 GPa) is substantially above that reported for other metal-metalloid deposits such as electroless and electroplated Ni-P coatings, which generally exhibit maximum hardness values of at most~8.8 GPa at substantially lower annealing temperatures (T < 500°C). [16][17][18][19][20][21][22] This strength enhancement after annealing suggests that ternary Cr-C-P coatings may find use in applications Fig. 4.-Effect of annealing temperature and phosphorus content on hardness of electrodeposited Cr-C-P coatings.…”