【摘要】：鎳基高溫合金因其具有較高的高溫強度、抗氧化性能及抗疲勞和蠕變等性能,在航空發(fā)動機關(guān)鍵熱端部件中有著廣泛的應(yīng)用。但我國高溫合金在航空發(fā)動機中的應(yīng)用技術(shù)還不是很成熟,原因之一是對國產(chǎn)高溫合金微觀結(jié)構(gòu)、組成相與其性能之間的關(guān)聯(lián)還缺乏比較系統(tǒng)的認(rèn)識。基于以上的問題,本文對國產(chǎn)渦輪盤用材料GH4169合金進(jìn)行了不同熱處理,重點研究了δ相含量對拉伸和低周疲勞行為的影響。主要內(nèi)容和結(jié)論如下：(1)采用三種不同的熱處理工藝對GH4169合金進(jìn)行熱處理,合金的顯微組織受熱處理參數(shù)的影響較大。熱處理后,合金的組織中析出了不同含量的δ相。(2)對常溫拉伸試驗的研究表明,合金的拉伸行為明顯受到6相的影響。隨著6相含量的增加,合金的抗拉強度減小而延性增加。拉伸斷口的形貌因6相含量的不同也存在一些差異。(3)GH4169合金的常溫低周疲勞壽命基本不受δ相的影響,不同6相含量的合金具有相近的疲勞壽命。合金Coffin-Manson關(guān)系的塑性線具有雙斜率特征。同時,本文對合金的循環(huán)變形行為、斷裂方式和變形機理進(jìn)行了相應(yīng)的分析。(4)GH4169合金在650℃下的低周疲勞壽命在高應(yīng)變幅(Aεt/20.6%)下基本不受δ相含量的影響；在較小應(yīng)變幅下(△εt/2=0.5%)的疲勞壽命具有一定的分散性,并隨著6相含量的增加而增加。合金Coffin-Manson關(guān)系的塑性線不具有雙斜率特征。
[Abstract]:Nickel-based superalloys have been widely used in aero-engine because of their high temperature strength, oxidation resistance, fatigue resistance and creep resistance. However, the application technology of superalloy in aeroengine in China is not very mature, one of the reasons is the lack of a systematic understanding of the relationship between the microstructure, phase composition and properties of domestic superalloys. Based on the above problems, different heat treatment was carried out on the GH4169 alloy, a domestic material for turbine disk, and the effect of 未 phase content on tensile and low cycle fatigue behavior was studied. The main contents and conclusions are as follows: (1) the microstructure of GH4169 alloy is greatly affected by heat treatment parameters by using three different heat treatment processes. After heat treatment, 未 phases with different contents were precipitated in the microstructure of the alloy. (2) the tensile behavior of the alloy was obviously affected by the 6 phases in the tensile test at room temperature. With the increase of 6 phase content, the tensile strength decreases and the ductility increases. (3) the low cycle fatigue life of GH4169 alloy at room temperature is not affected by 未 phase, and the fatigue life of the alloy with different content of 6 phases is similar. The plastic line of Coffin-Manson relation of alloy has double slope characteristic. At the same time, the cyclic deformation behavior, fracture mode and deformation mechanism of GH4169 alloy are analyzed. (4) the low cycle fatigue life of GH4169 alloy at 650 鈩，

本文編號：2243697