Experimental study of binding copper powders by electrochemical deposition

Abstract

Binding of metal powders using electrochemically deposited binders provides a novel approach to achieve metal additive manufacturing at ambient temperature. In this study, using an in-house built experimental setup, a single layer of copper powders were electrochemically bound together with the help of nickel binder and the deposits were studied by scanning electron microscope and energy-dispersive X-ray spectroscopy. Mechanical characterization performed on the deposits reveals that the yield strength of the deposit is comparable to that of laser-sintered parts made from Cu/Ni powder. Furthermore, Taguchi studies have been conducted to investigate the optimal process parameters required for minimum diameter of electrochemically bound spot, layer thickness and yield strength. Analysis of variance and signal-tonoise ratio were used to determine the important levels of process parameters and the results were then experimentally verified.

A mathematical model for the estimation of hardness of electrochemical deposits

“…The in-house built experimental setup used for the electrochemical binding process is shown in Figure 2. 10 The electrolyte tank houses the cathode (brass, aluminum). The substrate is clamped by a metallic device which is in turn connected to the negative terminal of a pulsed power supply.…”

“…8,9 Binding of metal powders using electrochemically deposited binder enables additive manufacturing of metal parts without thermal defects. 10 In this method, a layer of copper powder is bound together by using Nickel from the electrolyte as a binder. Knowing the hardness of the bound part is an important prerequisite to assess the commercialization potential of ECAM.…”

“…The hardness value can be approximated to get a yield strength value of the part. 10 Since the thickness of the deposit is very less, substrate effects come into play when measuring the hardness values of the part through nanoindentation. Due to the small thickness, directly measured hardness values are usually influenced by the substrate.…”