Guozhen Chen

Effect of Zr addition on microstructure and properties of Al–Mn–Si–Zn-based alloy

Abstract Effects of Zr addition on the microstructure, mechanical and electrochemical properties of Al–Mn–Si–Zn alloy were investigated. Transmission electron microscopy (TEM) observations reveal that, in as-annealled state, the precipitates in the Zr-containing alloy are finer and more dispersive than those in the Zr-free alloy. Whereas, in simulated brazing state, a weaker precipitation is found in the Zr-containing alloy. Tensile testing results indicate that, with Zr additon, comprehensive mechanical properties of the as-annealed alloys could be significantly improved but weakened for the simulated brazing alloy. Electrochemical testing results reveal that, with Zr addition, the corrosion resistance of the as-annealed alloy decreases. However, after the simulated brazing treatment, such a negative effect of Zr element on the corrosion behavior of the alloy could be negligible.

Effect of Zn content on tensile and electrochemical properties of 3003 Al alloy

The effect of Zn addition on the microstructure, tensile properties and electrochemical properties of as-annealed 3003 Al alloy was investigated through TEM observations, tensile tests and Tafel polarization analysis. High density precipitates are observed in the Zn-containing alloys and the alloy with 1.8% Zn addition also has rod-like precipitates. Tensile test results indicate that Zn has a great effect on tensile strength of 3003 Al alloy. The alloy with 1.5% Zn addition has the highest ultimate tensile strength. The electrochemical results indicate that Zn addition to 3003 Al alloy also has great impact on the corrosion potential of the 3003 Al alloy in 0.5% NaCl solution and ethylene glycol-water solution. The corrosion potential varies with the Zn content and shifts negatively.

Effect of CeLa addition on the mechanical properties of Al–Cu–Mn–Mg–Fe alloy

The rapid development of new energy automobiles leads to an increasing demand for high-strength lithium battery shell alloy. The microstructures, electrical conductivity and mechanical properties of CeLa-containing Al–Cu–Mn–Mg–Fe alloys were investigated with scanning electron microscopy (SEM), X-ray diffraction, Eddy Current conductivity tester, tensile testing and Erichsen cup testing. Experiment results indicate that Al6(Mn, Fe) particles could be refined by CeLa alloying and AlCuCeLa phase nucleates and grew up at the surface of Al6(Mn, Fe) particle. Major texture of the CeLa-containing alloys was different from that of the CeLa-free alloy. The electrical conductivity decreased with increase of the CeLa content. CeLa addition could greatly enhance the tensile strength of the alloy at temperatures ranging from –40°C to 300°C.

Effect of Zn Addition on the Microstructure and Properties of Simulated-Brazing 7072Al Alloy

7072Al is widely used as cladding layer for heat-transfer components. In this paper, the microstructure, mechanical properties and electrochemical properties of simulated-brazing 7072Al alloy with Zn addition were investigated. Transmission electron microscopy (TEM) observations revealed that, in the simulated-brazing state, Zn-addition could promote the precipitation in the 7072Al alloy. Tensile testing results indicated that, in comparison with 7072Al alloy, the mechanical properties were improved after Zn-addition. Electrochemical testing results revealed that the simulated-brazing alloy showed a negative shift of the corrosion potential with the addition of Zn element.

Microstructure and Electrochemical Properties of Ce-Containing 7072 Al Alloy

The microstructure and electrochemical properties of Ce-containing 7072 Al alloy were investigated through transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Tafel polarization analysis. It was found that Ce alloying could result in a formation of finer grains in the simulated brazing alloys. The 7072 Al alloy with 0.15% Ce had desirable distribution of precipitates. The electrochemical testing results indicated that Ce element had a great impact on the corrosion potential of the alloy tested in 0.5% NaCl solution. Alloying with 0.15% Ce element could make the corrosion potential shift to inert direction and reduce the corrosion current density. An excessive Ce addition could weaken its positive effect on the corrosion resistance of the Ce-containing alloy.