Electrodeposited Iron Group Thin-Film Alloys: Structure-Property Relationships

Abstract

Various iron group alloys have been electrodeposited and evaluated for properties including corrosion resistance, microstructure, electrical resistivity, magnetoresistance and other magnetic properties. Corrosion resistance depends on deposit composition and microstructure, which are controlled by solution composition and deposition variables. Maximum corrosion resistance was observed for 50Ni50Fe and 70Co30Ni binary alloys. The corrosion resistance of electrodeposited CoFe films was an order of magnitude lower than CoNi and NiFe films. Substantially increased corrosion resistance was obtained by adding Ni to CoFe alloys. However, addition of B only slightly increased corrosion resistance. For electrodeposited NiFe and CoNi thin film alloys, three distinct structural regions were observed: for NiFe alloys, fcc, mixed fcc and bcc, and bcc phases as deposit Fe content increased; for CoNi alloys, fcc, mixed fcc and hcp, and hcp as deposit Co content increased. The smallest grain size was obtained in the mixed phase region of both NiFe and CoNi alloys. For CoFe alloys, a mixed phase region was not observed; only fcc and bcc phases were obtained. Electrodeposited NiFe films from sulfate baths show superior soft magnetic properties including both lower coercivity and higher squareness than from chloride baths. Magnetic saturation (M S ) of electrodeposited NiFe films follow bulk alloys where magnetic saturation increased with increased deposit Fe content.

Preparation and characterization of electrodeposited iron + cobalt thin films from a chloride bath

“…Ferromagnetic alloys, e.g., Fe-Co and Fe-Ni have received considerable attention for their practical applicability in modern industries, such as rocketry, computers, space technology, etc. 6,[14][15][16][18][19][20][21][22][23] Myung and Nobe 18 detected that the corrosion resistance of Fe-Co 91 Preparation and Characterization of Electrodeposited Iron + Cobalt Vol. 17, No.…”

“…13 Literature on the electrodeposition of alloys of the iron group metals (Ni, Fe, Co and Zn), is rather extensive, comprising several papers. [14][15][16][17][18] These alloys have many useful properties such as high internal strength, hardness, high corrosion resistance and unusual magnetic properties. Many magnetic alloys with different compositions are widely employed for various purposes.…”

“…Ferromagnetic alloys, e.g., Fe-Co and Fe-Ni have received considerable attention for their practical applicability in modern industries, such as rocketry, computers, space technology, etc. 6,[14][15][16][18][19][20][21][22][23] Myung and Nobe 18 detected that the corrosion resistance of Fe-Co alloys were an order of magnitude lower than Fe-Ni and Co-Ni. On the other hand, the same authors determined the substantial increase in corrosion resistance by addition of Ni to Fe-Co deposits and the slight effect on this parameter with addition of B. Lallemand et al 20 observed that the codeposition of cobalt and iron leads to a reduction of the reaction rate of the more noble component and an increase of the reaction rate of the less noble component even if organic additives are adsorbed on the electrode surface, and affecting the polarization curves of single metals.…”

Characterization of the passive films on electrodeposited Fe-Ni-Cr alloys in borate solution at pH 8.4

“…In the literature, research illustrates the structure-property relationship of electrodeposited iron based alloys of various compositions produced with different deposition variables [35,36]. A number of alloys of amorphous-nanocrystalline structure have been reported to exhibit good corrosion resistance compared to other variants.…”

Micromechanical characterization of electroplated permalloy films for MEMS

“…The permalloy magnetic film can be elaborated by electrodeposition and micromachining (Quemper et al 1999), and the thickness of the film can range from nanometer scale to millimeters scale. The technologies for characterizing the magnetic and electrical properties of permalloy film are fairly well developed (Myung and Nobe 2001;O'handley 2000). However, little research has been conducted on their mechanical properties such as Young's modulus, fracture strength, fracture strain etc.…”