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积分854最后登录1970-1-1阅读权限255积分854帖子精华 
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| 抄一段话。<br/>Iridium is one of the platinim series elements, and some time ago was the prefered tipping material once a method was discovered to weld it
 to other metals -- it occurs in Central Asia, I think, as free granular
 material. It is quite hard, and provides a long wearing contact point.<br/><br/>However,
 it is both much to expensive and much to difficult to form to make a
 whole nib out of -- nibs were typically steel or iron until tippng
 material became available (several were used, including diamonds
 shellaced to tourtise shell!) because gold, while it is very corrosion
 resistant, quite flexible in copper alloys, and looks nice, wears off
 rather quickly, and is much to expensive to use if it won't last.<br/><br/>
  ure natural iridium has not been used for nib tips for some time, probably
 since the 1930s, when metallurgy improved to the point where pure
 material could be refined from ore rather than just used as found, and
 electric arc welding replaced white phosphorus ignition as a means off
 attaching it tp steel, gold, or whatever.<br/><br/>Gold alloy works very
 well for pen nibs -- corrosion resistant, fairly to very flexible and
 nicely malleable without being easily deformed, and pretty. However,
 it's never been inexpensive. <br/><br/>
  lain steel works just fine, but corrodes in the presence of water, let alone some of the inks used over
 the last couple hundred years, some of which are quite acidic or
 caustic. Stainless steel (high nickel and chromium content) is much
 more corrosion resistant, and can have a range of tensile
 characteristis, from quite hard to fairly soft. Works very well for pen
 nibs, although it is not as corrosion resistant as gold. I've seen
 quite a few vintage nibs badly corroded by ink, even up to the 1950s
 when Superchrome ink was sold by Parker -- that stuff ate stainless
 pretty quickly. Modern inks won't touch modern stainless nibs so far as
 I know, and a stainless nib works fine. In fact some of my favorite
 pens are Wearever's from the '40's with stainless nibs.<br/><br/>To make
 a stainless nib look like a gold one, many makers plated them with
 gold. This does provide some corrosion protection (the plating is 14kt
 gold, after all), but it wears off easily and once scratched loses it's
 corrosion resistance.<br/><br/>Other materials are also used to plate
 nibs, sometimes for functional reasons, sometimes just for looks.
 Sheaffer used platinum or palladium (I think palladium, not sure) on
 their two-tone nibs for many years, including the nib slit, partially
 for the look and partially for better ink flow down the slit. Parker
 plated their "arrow" nibs with palladium for a two-tone effect, but not
 the slit. Some modern nibs are plated with rhodium, don't know whether
 for looks or for function -- occasionally, the plating will cause rough
 spots on the nib tipping and require wearing off to get a smooth pen,
 as the nib is plated after the tipping is applied and rhodium won't
 stick all that well, I don't think. <br/><br/>As far as the "best" nib
 material, all things are a compromise. Gold works very well, but it's
 expensive (figure $80 difference in price these days, maybe more).
 Stainless is much less expensive, but not as good. Tipping materials
 are proprietary, and who knows what they are now -- Parker used
 ruthenium for some time, but it's softer than whatever alloy Sheaffer
 used at the same time. It's fairly common to find Parker pens from the
 40's through the 60's with worn tipping, while Sheaffer nibs very
 rarely show such wear. <br/><br/>
  eter<br/> | 
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