On Monday, February 13, 2012 02:24:49 PM Roland Jollivet did opine: > ..snip > > I would imagine... that the oxide layer is way way thinner than a micron > in thickness, and while tough as you say, in climb milling the cutter > tip will hit the metal and with the eggshell effect, simply push past > the oxide layer.
In electronics, my specialty, we have a tendency to rate this oxide film by its voltage withstand capability, which in the above mentioned .001 seconds is about 40 volts. This insulation BTW is perfect, and is considered to be degraded if a single electron succeeds in penetrating it. Leave it out in the 19% oxygen air for a few weeks, or help it along with a hydroxide bath and it can exceed 400 volts. That is quite a bit more than a micron although I don't have a thickness/voltage conversion table handy ATM. > I think that if this was a general problem, it would receive more alerts > in industry, although some shopfitting sections which are already > anodized, do take their toll on the saw blades. That has been noted, I've nicely rounded the teeth of several Starret hacksaw blades on the stuff myself, on one particular piece even breaking the teeth completely off! So I tend to steer clear of colored alu as raw material. :) > Regards > Roland Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> Flattery is like cologne -- to be smelled, but not swallowed. -- Josh Billings ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
