(北京有色金屬研究總院 有色金屬材料制備加工國家重點實驗室，北京 100088)
摘 要: 采用室溫水和濃度為20%的PAG水溶液 (聚烷撐二醇聚合物)作為淬火介質(zhì)進行Jominy末端淬火實驗，用于評價7050鋁合金淬透性；監(jiān)測合金固溶和淬火過程中的升溫速率和冷卻速率，測定距淬火端不同距離的合金的淬火態(tài)電導(dǎo)率和時效態(tài)硬度，觀察室溫水淬火試樣不同位置晶內(nèi)淬火析出相。結(jié)果表明：采用室溫水和20%PAG進行末端淬火時，合金的淬透深度分別約為65和40 mm；采用PAG淬火可使合金溫度快速通過淬火敏感區(qū)間，同時在淬火敏感區(qū)間外降低合金的冷卻速率，使試樣淬火端和中間部位合金的溫度差減小。隨著距淬火端距離的增加，淬火誘發(fā)析出的η平衡相的尺寸和體積分?jǐn)?shù)增加，無析出區(qū)寬化。
關(guān)鍵字: 7050鋁合金；Jominy 末端淬火; 淬火介質(zhì); 淬透性
Jominy end quench behavior of 7050 Al alloy
（State Key Laboratory of Nonferrous Metals and Processes,
General Research Institute for Nonferrous Metals, Beijing 100088, China）
Abstract:The Jominy end quench test was used to evaluate the hardenability of 7050 Al alloys. The room-temperature water and 20%PAG were adopted as quenching media respectively in this test. The heating and cooling rates of the 7050 bar were monitored. The as-aged hardness and as-quenched electrical conductivity of alloys at different distances from the quenched end were collected, and the intragranular precipitates at different locations of samples quenched by room-temperature water were observed. The results indicate that the quenched depths of the alloy are 65 and 40 mm for the alloy quenched by room-temperature water and 20%PAG, respectively. The alloy can pass through the quench sensitive temperature range rapidly when quenched by 20%PAG, the cooling rate can be reduced outside that range, and the temperature difference between the quenched end and center parts of the quenched bar is decreased. The size and volume fraction of the quench induced equilibrium η phase as well as the width of the PFZs increase with the distance from the quenched end increasing.
Key words: 7050 Al alloy; Jominy end quench; quenching media; hardenability
