Electrodeposition of Aluminum‐Tin Alloys from Organic Electrolytes

Abstract

Aluminum‐tin alloys were electrodeposited onto steel from alkyl benzene, AlBr3‐normalHBr electrolytes. Bright, adherent, and coherent aluminum‐tin coatings were obtained at cathode efficiencies approaching 100%. The composition of the cathode deposit can be readily controlled by using Al‐Sn anodes of specified tin content. If the current density, agitation, and specific conductance are maintained constant, the electrolyte tin concentration acquires a constant value after a working up period. With electrolytes having conductivities of 3–6×10−3 Ω−1 cm−1 , 100% of the tin dissolved from the anodes is transferred to the cathode, whereas, with electrolytes having conductivities of 2–3×10−3 Ω−1 cm−1 , only about half the tin content from the anodes is actually electroplated. The codeposition of tin in the electrodeposition of aluminum‐tin alloys was found to be a diffusion rate controlling process.

Promoting the high load-carrying capability of Al–20 wt%Sn bearing alloys through creating nanocomposite structure by mechanical alloying

“…To overcome those drawbacks, different preparing methods, including stircast [5], rapid solidification [6][7][8], physical vapor deposition [9][10][11], electrodeposition [12], powder metallurgy (P/M) [13,14], and severe plastic deformation [15], have been used to improve microstructure homogeneity and refine the size of Sn and Al phase in Al-Sn alloys. Many previous works demonstrate that refinement of microstructure is usually beneficial to mechanical and tribological properties of Al-Sn alloy [16][17][18].…”

The Electrodeposition of Aluminum and Aluminum Alloys from Alkylbenzene ‐ HBr Electrolytes: Theoretical Considerations and Applications

“…A process for the electrodeposition of aluminum and aluminum alloys has been extensively studied in our laboratory in the last decade (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). The plating solution consists of a mixture of ethylbenzene and toluene saturated with A1Br3.…”

“…It has been observed experimentally (9) that at a fixed potential an increase in the conductivity of the electrolyte produces a higher current density. Equation [4] has been very useful in explaining certain phenomena in the electrodeposition of aluminum alloys (12,13) whereby the minor constituent concentration of the alloy coating varies with the specific conductance and hence with the addition of HBr (Fig. 1).…”

“…The aluminum alloy coatings studied in our laboratory are: aluminum-copper ( 6), aluminum-zinc (12), and aluminum-tin (13) in which copper, zinc, and tin were the minor constituents.…”

“…This assumes that~ in the absence of the metal deposition, the potential applied to the electrode remained constant. Equation [13] also shows that the time of formation of a nucleus is a function of the overvoltage.…”