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对Zr-Sn-Nb合金带材在25、200、400℃下进行拉伸试验,采用背散射电子衍射(EBSD)技术研究了织构对锆合金力学性能的影响。结果表明,带材具有较强的{0001}基面双峰织构,[0002]基轴在TD-ND平面内,并向TD方向倾斜约30°,大晶粒多为{0001}<1010>和{0001}<1120>取向,小晶粒为{0001}<1010>取向。织构造成带材力学性能呈现各向异性,σ_s在TD方向最高,在RD方向最低;σ_b在RD方向最高,在45°方向最低。随着温度的升高,σ_s与σ_b都有所降低,Δσ_s与Δσ_b也随之减小,且Δσ_s较Δσ_b受温度的影响更为明显。带材的延伸率随温度升高而增大,但400℃时的延伸率较200℃时的低,晶界强度的下降以及动态应变时效是造成这种现象的主要原因。
Tensile tests were carried out on Zr-Sn-Nb alloy strip at 25,200,400 ℃. The effect of texture on the mechanical properties of zirconium alloy was studied by backscattered electron diffraction (EBSD). The results show that the strip has a strong {0001} basal plane bimodal texture. The base axis is in the TD-ND plane and is tilted about 30 ° in the TD direction. The large grains are mostly {0001} <1010 > And {0001} <1120> orientations, with small grains oriented {0001} <1010>. The mechanical properties of ribbons are anisotropic. Σ_s is highest in TD and lowest in RD; σ_b is the highest in RD and lowest in 45 °. As temperature increases, σ_s and σ_b decrease, Δσ_s and Δσ_b decrease, and Δσ_s is more affected by temperature than Δσ_b. The elongation of the strip increases with increasing temperature, but the elongation at 400 ℃ is lower than that at 200 ℃. The decrease of the grain boundary strength and the dynamic strain aging are the main causes of this phenomenon.