Thread: castting
View Single Post
  #9   Report Post  
Posted to rec.crafts.metalworking
[email protected] edhuntress2@gmail.com is offline
external usenet poster
 
Posts: 556
Default castting

On Thursday, April 20, 2017 at 4:35:22 PM UTC-4, Jim Wilkins wrote:
wrote in message
...
On Thursday, April 20, 2017 at 4:01:48 PM UTC-4, Tim Wescott wrote:
On Thu, 20 Apr 2017 17:33:33 +0100, David Billington wrote:

On 20/04/17 06:29, wrote:
I am research student I need any one interest in casting of
copper base
alloy or high copper alloy with chrome in different ratios
(0.46 - 5)%
chrome and copper base alloy with aluminum in different ratios
(3 -9)%
Al ,I need know how can cast of chrome in molten copper that has
1907 C
temp whereas the copper 1085 C, can I add chrome to molten copper
as
powder? Did the chrome dissolved in molten copper.
then I will try to make solution treatment to these alloy for
strengthening (quenching and aging) to ...then I will to compare
between these alloy with mechanical properties, corrosion and
wear
resistance. Please if you any one can help me to achieved these
requirements. Did the copper chrome alloy has more than
properties from
copper aluminum alloy with the ratios above Thank with my regards
You would need to know the solubility of chrome in copper to know
how
much you can add but modern pewter (Britannia metal) is made by
melting
tin and then adding the copper and stirring to dissolve the
copper.
Copper has a much higher melting temperature than tin but will
readily
dissolve up to a point.


I did a bit of searching and based on the little bits I found it
seems
they're imiscible.

I was hoping to find a master chart of the solubilities of all
metals in
all metals -- I was disappointed.

--
Tim Wescott
Control systems, embedded software and circuit design
I'm looking for work! See my website if you're interested
http://www.wescottdesign.com


Copper and chromium are not miscable, but they are somewhat soluble,
and there is a whole class of copper/chromium alloys:

https://www.copper.org/resources/pro.../chrom_cu.html

When the alloy is cooled, the chromium either goes into solid solution
(fast quench) or it precipitates out (slow quench). The usefulness of
the alloy depends upon further heat treatment, which allows a fine
matrix of chromium to precipitate out of the alpha copper, resulting
in a very strong, precipitation-hardened alloy.

You probably can find more by looking up the individual Copper Assn.
alloy numbers, which are listed in the article linked to above.

Corrosion resistance of precipitation-hardened alloys typically is not
very good, but I have no idea about this pair.

As for the aluminum, I'd start with the big handbooks from the
American Society for Metals. I can look it up but it's worthwhile for
the OP to make himself familiar with the resources. This is pretty
obscure stuff and you have to find your way around the basic
references if you're going to get anywhere with complex and obscure
questions such as these.

--
Ed Huntress

================

The copper-aluminum alloy is called a Bronze:
https://en.wikipedia.org/wiki/Aluminium_bronze
-jsw


I think he said chromium/copper/aluminum, but yeah, plain aluminum bronze is quite common -- and very strong.

With the chromiun/copper, the question is whether he wants a solid solution or the precipitation-hardened version. The precipitation process is commonly called "aging," but I don't know if this alloy will age naturally, like 6061 aluminum.

--
Ed Huntress