加工对新型锆合金板材均匀腐蚀和拉伸性能的影响

Effect of Working on Uniform Corrosion and Tensile Properties of Sheets of a New Zirconium Alloy

新型锆合金板材在750℃~800℃热轧3或4道次后再冷轧,冷轧后在540℃~600℃退火1.5~50 h。本实验研究了加工引起的微观组织改变,分析了微观组织改变对均匀腐蚀性能和拉伸性能的影响。结果表明:原板材和加工板材均为部分再结晶态,加工没有显著影响织构。在冷轧和退火过程中有细小的第二相析出,但加工板材基体中细小第二相比原板材少。加工之后板材的均匀腐蚀性能得到了改善。基体缺陷密度是影响均匀腐蚀性能的主要因素。选取原板材和580℃短时退火的加工板材对比分析了室温和375℃下的拉伸性能。总体而言,加工之后强度降低,塑性有所提高;不同加工工艺获得的板材力学性能差距不大。第二相是影响力学性能的主要因素。

Sheets of a new zirconium alloy were undergone hot-rolling at 750˚C~800˚C for 3 or 4 passes, sub-sequent cold-rolling and final annealing at 540˚C~600˚C for 1.5~50 h. In this study, the change in the microstructure caused by the working was investigated, and the effect of the microstructure change on uniform corrosion and the tensile properties was analyzed. The results showed that both original and worked sheets are partially recrystallized and working did not influence the texture. In the process of cold-working and followed annealing, fine particles were precipitated. However, the quantities of the fine particles in the matrixes of worked sheets were less than that of the original. The resistance of uniform corrosion is improved after the working. The defect concentration in the matrix is the dominant factor influencing the uniform corrosion. The original sheets and worked sheets annealed at 580˚C for a short time were selected to compare tensile properties at room temperature and 375˚C. In general, strengths decrease but the plasticity slightly increases after the working. Tensile properties of sheets with various working processes show little difference. The quantity of secondary phase is the principal factor affecting the mechanical properties.