鎳基高溫合金端淬梯度冷卻過(guò)程中γ′相演化規(guī)律鎳基高溫合金端淬梯度冷卻過(guò)程中γ′相演化規(guī)律Gamma prime phase evolution rule during end quench cooling in nickel-based superalloy 研究熱處理過(guò)程中不同冷卻速率對(duì)鎳基高溫合金中γ′相析出的影響；采用Thermal-calc熱力學(xué)計(jì)算、差熱分析技術(shù)，確定新型鎳基高溫合金的γ′相完全固溶溫度；采用有限元模擬、掃描電鏡分析等方法，研究端淬梯度冷卻過(guò)程中合金的溫度場(chǎng)分布及γ′相析出和演化規(guī)律。結(jié)果表明：該合金γ′相完全固溶溫度為1140 ℃，在端淬梯度冷卻過(guò)程中，距離噴水端越遠(yuǎn)，冷卻速度越低；隨著冷卻速度的逐漸減小，γ′析出相的體積分?jǐn)?shù)逐漸增加，γ′析出相的形貌由球形向方形逐漸轉(zhuǎn)變，平均尺寸逐漸增大；時(shí)效后合金中析出大量細(xì)小三次γ′相，合金硬度增加。 The effect of cooling rate during the heat treatment on the gamma prime phase precipitated in the nickel-based superalloy was studied. The solution temperature of the new type nickel-based superalloy was obtained by the thermal-calc software and differential thermal analysis (DTA) test, respectively. Based on end-quenching cooling, the effect of cooling rate on the microstructure of the nickel-based superalloy was studied. The finite element was used to simulate the temperature filed distribution. The results show that with the increase of cooling rate, gamma prime phase volume fraction increases gradually, and the morphology of gamma prime phase changes from spherical to square, the size of the precipitate phase always decreases with the increase of the cooling rate. After aging, there are a large number of 3rd gamma prime phase precipitate, inducing the increase of Vickers hardness.
|
