(中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙410083)
摘 要: 利用高溫拉伸力學(xué)性能測試、掃描電鏡與透射電鏡等分析手段對2519A鋁合金在不同溫度與保溫時間下的高溫力學(xué)性能進行研究。結(jié)果表明：合金在保溫10 min后進行拉伸，從室溫至400 ℃，隨著溫度的升高，抗拉強度從471 MPa下降至55.5 MPa，屈服強度從440.3 MPa降至50.3 MPa，延伸率由11.6%提高至21.3%。300 ℃時，隨保溫時間的延長，合金的抗拉強度先由171.6 MPa下降至151.4 MPa，屈服強度由139.4 MPa降至130.5 MPa，１ h后基本上穩(wěn)定不變。高溫條件下，該合金力學(xué)性能的下降主要是由于析出相的粗化與轉(zhuǎn)變引起的。
關(guān)鍵字: 2519A鋁合金；高溫力學(xué)性能；顯微組織
（School of Materials Science and Engineering,Central South University, Changsha 410083, China）
Abstract:The elevated-temperature mechanical properties of aluminum alloy 2519A annealed at different temperatures and different holding times were investigated by tensile test, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that for the holding time of 10 min, with increasing of temperature from room temperature to 400 ℃, the ultimate tensile strength descended from 471 MPa to 55.5 MPa, the yield strength from 440.3 MPa to 50.3 MPa, and the elongation rised from 11.6% to 21.3%. At 300 ℃, with the prolongation of holding time, the ultimate tensile strength descended from 171.6 MPa to 151.4 MPa and the yield strength from 139.4 MPa to 130.5 MPa, and then they had no remarkable changes after 1 h. At high temperatures, the decrease of the mechanical properties of the studied alloy was due to coarsening and transformation of the precipitates.
Key words: aluminum alloy 2519A; elevated-temperature mechanical properties; microstructure
