Study On Effect Of Annealing Condition On High Temperature Oxidation Resistance Of CuSi Microalloy

Copper?Cu?,as an important metal in human production and life,is widely used because of its good electrical and thermal conductivity.With the rapid development of modern industrial society,Cu is not only widely used in ultra-large-scale integrated circuits and power lines,but also plays an important role in many aspects,such as aerospace and bridge construction.For example,in the aerospace field,high temperature,pressure and atmospheric friction all put forward higher requirements for the high temperature oxidation resistance of Cu.In the existing methods for improving the oxidation resistance of Cu,Cu alloying,painting,and passivation are usually adopted.However,while improving the oxidation resistance of Cu,it is inevitable to sacrifice its mechanical properties or environment.Working-life may also be shortened.Therefore,under the condition of ensuring good mechanical properties of Cu,it is very important to improve its oxidation resistance under high temperature condition.Based on the alloying theory and the many advantages of element Si?rich content,low cost,strong oxygen affinity and not easy to acid-base reaction,etc.?,this article mainly studies the alloy element Si content and different heat treatment schemes on the high temperature oxidation of Cu alloys.The effect of performance and its mechanism of action provide reliable data support for expanding the application range of Cu under the premise of environmental protection.For this reason,this paper takes Cu-xSi?x:0.2,0.5,1.0 and 2.0 wt.%?microalloys as the research object to study the influence of Si content on the oxidation resistance of CuSi alloys.On this basis,the effect of annealing process?annealing temperature,cooling method and holding time?on the oxidation resistance of CuSi alloy and its mechanism will be studied further.The research results show that,with the increasing of the annealing temperature and the content of alloying elements,CuSi alloy exhibits better oxidation resistance under high temperature conditions.During the high temperature annealing process at 900oC,the alloying element Si fully diffuse to the surface of the alloys owing to its good oxygen affinity,and subsequently react with the remnant O₂ in the annealing atmosphere.Therefore,a protective SiO₂ film was formed on the surface of the alloys.Combined with the background of industrial applications,we also examined the influence of cooling method and annealing time on the oxidation resistance of CuSi alloys.It is found that the quality of the protecitive layer basically reached the optimal value when the annealing temperature was above 800oC or the annealing time was reduced to 18 h.In this case,the SiO₂ protective film formed on the surface of the CuSi alloys can protect the alloy matrix from oxidation.