Message:

<p>[QUOTE=&quot;-jeffB, post: 26026629, member: 27832&quot;]Getting big crystal grains like that requires fairly pure metal, but I think the more important factor is <i>very slow cooling</i>. Makes me want to try making some myself.</p><p><br /></p><p>(I did have to laugh at the bit about 99.99 being &quot;the purest copper commercially obtainable&quot; - especially coming from a company that claims to sell to the semiconductor industry, where 99.9999 sometimes isn&#039;t quite pure enough!)</p><p><br /></p><p>I&#039;m remembering a tale from a materials-science friend, about a group that had ordered in a block of specially-annealed copper for some specialized use, at great expense. One of the lab workers dipped it in a solvent to remove any surface residue, then removed it and gave it a good shake to get rid of most of the liquid - and the block <i>wrapped around his hand</i>. And, of course, bending it work-hardened it, so it was ruined.[/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