摘要
针对不同热轧工艺制备的7B50-T7751铝合金厚板,通过金相显微镜、EBSD等方法对合金的组织特征进行了表征与分析,并对比分析了不同热轧工艺制备的板材的室温拉伸性能和断裂韧性。结果表明,轧制过程使板材织构呈不均匀分布,板材1/4厚度位置主要是变形织构;1/2厚度位置主要是再结晶织构,织构强度较1/4厚度位置的弱。通过较少轧制道次、提高道次变形量、提高终轧温度可以使板材在热轧过程中充分回复,释放变形储能,在后续热处理后不同厚度位置均保留变形织构。变形织构可以有效提高合金的断裂韧性和拉伸性能,同时也增加了厚板的各向异性。
The microstructure characteristics of 7 B50-T7751 thick plate after different hot rolling processes has been investigated by optical microscopy( OM) and electron back scatter diffraction( EBSD). The fracture toughness and tensile properties at room temperature have also been tested. The results indicate that the plate texture is unevenly distributed due to the rolling processes,1/4 thick position is mainly deformation texture and 1/2 thick position is primarily recrystallized texture. The texture strength of 1/2 is weaker than that of1/4. By reducing rolling passes,improving pass deformation and finishing rolling temperature,the plate can fully recover,release deformation storage energy and reserve deformation texture at different thickness positions in the rolling processes. The deformation texture can improve the fracture toughness and tensile properties effectively,and increase different directions of anisotropy.
引文
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