Message:

<p>[QUOTE=&quot;Pete Apple, post: 26134651, member: 103982&quot;]<b>There are two primary areas still to be addressed. One is the applicability of studies (as discussed in the paper) of copper deposition at the crystalline level to the corrugation features easily and commonly seen on many CPZ cents. The other is the mechanism by which the ridges and valleys are oriented in approximately the same direction on both sides of the planchet/coin.</b></p><p><br /></p><p><b>In addition to crystal behavior at the atomic level Current Density and Electrolyte Flow influence the formation, direction and orientation of the ridges and valleys of a corrugated surface. In research carried out by the Bureau of Mines to develop new technology for electrorefining metals, the hydrodynamics of electrolyte flow were studied:</b></p><p><br /></p><p><b>“The cathode deposits are relatively smooth but with striations or grooves running parallel to the electrolyte flow. Many of the striations were continuous along the entire length of the cathodes. Their origin is believed to reflect the hydrodynamic flow conditions close to the surface. It appears that either a ridge or groove, once initiated at the front edge of the cathode, propagates along the entire length.” (<a href="https://www.911metallurgist.com/blog/electrorefining-copper/" target="_blank" class="externalLink ProxyLink" data-proxy-href="https://www.911metallurgist.com/blog/electrorefining-copper/" rel="nofollow">https://www.911metallurgist.com/blog/electrorefining-copper/</a>) </b></p><p><br /></p><p><b>{In barrel electroplating, the object being plated acts as the cathode}</b></p><p><br /></p><p><b>A barrel plating process is used by the supplier of Cent Ready-to-strike (RTS) planchets for the US Mint. Barrel rotation is likely a key factor contributing to the formation of ridges and valleys and in their alignment in the same direction on both sides of the planchet/coin.</b></p><p><br /></p><p><b>►Current density varies, resulting in thicknesses that vary.</b></p><p><br /></p><p><b>►An electrolyte flow pattern is driven by the rotation of the barrel, resulting in striations or grooves running parallel to the electrolyte flow. </b></p><p><br /></p><p><b>►The result of these dynamics builds on the crystal orientation patterns developed at the atomic level.</b></p><p><br /></p><p><b>►The tumbling action of a metal disc in the barrel plating bath, as the barrel rotates, is most likely to be end over end, resulting in electrolyte flow patterns being in approximately the same orientation on both sides of the planchet. </b>[/QUOTE]</p><p><br /></p>

Your name or email address:

Do you already have an account?

• No, create an account now.
• Yes, my password is:
• Forgot your password?

Stay logged in