1. Introduction
2. Experimental Method
2.1 CRB and Annealing
Table 1
Si | Fe | Cu | Mn | Mg | Cr | Zn | Ti | Each | Al | |
---|---|---|---|---|---|---|---|---|---|---|
AA5052 | 0.25 | 0.40 | 0.10 | 0.10 | 2.5 | 0.2 | 0.1 | - | 0.03 | RE |
2.2 Characterization
3. Results and Discussion
3.1 Microstructure
Fig. 2

Fig. 3

3.2 Mechanical Properties
Fig. 6

Fig. 7

Fig. 8

4. Conclusion
1) Both the 2-layer and 4-layer overlapped CRB AA5052 materials exhibited a typical deformed microstructure with grains significantly elongated in the rolling direction. The 200 and 250°C annealed materials also showed a slight increase in grain thickness due to recovery, but still exhibited a deformed microstructure. In annealing materials at 300°C or higher, complete recrystallization occurred, resulting in an equiaxed grain structure.
2) Both the 2-layer and 4-layer overlapped materials exhibited coarse and uneven microstructures in the central region compared to the surface region. Under the same annealing conditions, the grain diameter of the 4-layer overlapped material was smaller than that of the 2-layer overlapped material.
3) The CRB material in both the 2-layer and 4-layer overlap showed higher hardness at the surface compared to the central region, resulting in an uneven hardness distribution in the thickness direction. However, the annealing material at 250°C or higher showed a highly uniform hardness distribution. Furthermore, the average hardness gradually decreased up to 250°C, and then significantly decreased at 300°C or higher where complete recrystallization occurred.
4) The 2-layer and 4-layer overlapped materials displayed a characteristic softening curve, indicating a reduction in tensile strength and an increase in elongation with rising annealing temperatures. The 4-layer overlapped material exhibited enhanced strength and elongation properties relative to the 2-layer overlapped material.
5) From the above results, it can be concluded that it is possible to manufacture laminated AA5052 sheets with various strength-ductility combinations using 2- layer and 4-layer overlapped CRB. Furthermore, differences in the number of layers and annealing temperature significantly affected the mechanical properties of the laminated AA5052 sheets.