Oxidation protection of copper foam in sintering furnaces

The reason why copper foam does not oxidize
Copper foam is a porous material made from a mixture of metallic copper and a surface foaming agent, which is baked and expanded at high temperatures. In the sintering furnace, copper foam is easy to oxidize in the air because oxygen molecules can enter inside the foam through the foam pores and react with the copper to produce copper oxide. However, there are a large number of gas pores within the copper foam, and these gas pores can expel the oxygen molecules from the foam interior, thus realizing the effect of non-oxidation.
Protective Measures
Although there are a large number of gas pores inside the copper foam, if the atmosphere inside the furnace is not suitable it will still lead to oxidation. Therefore, in the sintering furnace, in order to protect the copper foam from oxidation, the following measures need to be taken:
1. Flow atmosphere control: Control the redox atmosphere in the sintering furnace by adjusting the thermal redox potential. Among them, the oxidizing atmosphere will accelerate the oxidation of copper foam, so it is necessary to reduce the content of oxygen and increase the content of reducing gas.
2. Surface coating protective agent: coating a layer of protective agent on the surface of copper foam can effectively resist oxidation. Commonly used protective agents are silicon oil, sintered carbon powder, aluminum oxide and so on. Among them, alumina can form a layer of stable alumina film to prevent further oxygen reaction.
The reason why copper foam does not oxidize in the sintering furnace is that there are a large number of gas pores inside it, which can expel oxygen molecules out of the foam interior. In order to protect the copper foam, it is necessary to control the flow atmosphere in the sintering furnace and to coat its surface with protective agents and other measures.