I am working on high temperature process (around 700 -900 degree centigrade) where Iron debris particles enter into the copper alloy. I would like to know how iron debris particles can affect the properties of copper alloy.
Iron as an impurity in copper will increase the electrical resistivity of the copper. Also iron impurity increases the recrystrallization temperature and reduces grain growth in copper but I doubt this is an issue as you are well above normal recrystallization temperatures. I am trying to undersrtand or visulaize your meaning of iron debris entering into the copper alloy, ( what alloy?) -- is this a duffusion process? iron can form some corrosion products depending on the atmosphere
for refence on the diffusion and solubility of iron in copper , you may find the following reference useful:
http://scitation.aip.org/content/aip/journal/jap/49/1/10.1063/1.324336
Dear Thomas,
I am working on two different copper alloys. One is commercial alloy with 99 % copper 0.4 % Fe and other alloy is CuCrZr alloy with 1 %Cr and .1% Zr. I am rubbing tool steel rod with these alloys at high temperature. during rubbing at high temperature steel is getting wear out and wear particle enters or mixed with copper alloys. I would like to know how wear particle of iron can affect copper alloy properties ?.
Let me know if you have some questions ?
In the solid state is possible the diffusion of iron in the alloys , the extent of diffusion depends on the temperature and duration.
Dear Petru
I agree with you there is a chance of diffusion of iron in the copper. I would like to know how diffusion of iron can affect the properties of above given copper alloys..
iN MY OPINION...
1) With the high temperature abrasion described, there will considerable oxidation of both the iron and the copper alloy and less likely to be any effective amout of Fe diffusion into the copper alloy with the oxide surface barriers.
2) Certainly in the case of Cu-Fe, the incremental increase in Fe content would be negligible compared to the oxidation of the iron component of the alloy at the surface.
3) In the case of CuCrZr, I am quite familiar with high temperature effects of this alloy. Unless the atmosphere is very reducing, oxidation of the Cr and Zr content in the alloy at the surface will occur and with time, this layer may grow to 2 or 3 mm. The copper rich surface with oxidized Cr and Zr will effectively reduce the hardness to that of pure copper, and the resistance to further softening wilo be negligible. so it is likely the CuCr Zr alloy will begin to wear severly by galling. Any small amount of Fe difussion into the copper alloy would be minimal, but would have the effect of decreasing thermal and electrical condictivity
A microprobe scan of a surface cross section would certainly show if tere is any diffusion of iron.
Now if this is carried out in vacuum or non oxidizing atmosphere, nearly everything above is negated.. in that case Fe in copper increases hardness somewhat and definitely reduces conductivity, both electrical and thermal.
Interesting discussion....thanks for posting
Further comment about operating temperature ...at 700 -900 C , both of these alloys wil lose any strength property gained from the age hardening or cold working . at 700 -900 C CuCr Zr will become overaged and quite soft..any other effect of Fe diffusing by couple with the coppermay be overshadowed
Dear Thomas,
I would like to appreciate your support and level of understanding of this discussion. I can understand you have much deep knowledge related to this interaction of copper and steel.
Please let me know at high temperature what will be the wear mechanism (adhesion or abrasion or any other) of steel during rubbing interaction of steel with copper. Please remember the steel is getting wear out during the interaction with copper.
As per your suggestion i will do the microprobe analysis of surface cross section of copper and steel. I will discuss with you the outcomes.
I beleive the wear mechanism could be either depoendent on the environment. If there is condierable oxide scale present, then some abrasion would seem likely.In the absence of heavy oxide scale , then adhesion ( or galling) is likely although I would think the copper would suffer in this case..I do not have specific expereince related to wear of copper alloy and steel at these temepratures.
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering
- Annealing
- Metallurgy