Structure and properties of Zn–Al–Cu alloys with alloying additives

In the present work the investigations concerning the influence of the modification with cerium on the microstructure and properties of the Zn–Al–Cu alloy was shown. The investigations were realized for Zn–Al–Cu samples with approximately 0.1% Ce in the form of Al–Ce master alloys added. The heat treatment was performed in a resistance furnace with a chamotte-graphite crucible. For the remelting, with cerium as an alloying element, an argon protective atmosphere was used. The treated alloy was cast into the metal casting dies. To determine the influence of the modification on the structure and properties of those alloys, the following investigations were carried out: transmission and scanning microscopy, EDSX-ray analysis, and hardness analysis. The modification of the chemical composition, properly realized, leads to the improvement of mechanical properties of the produced castings. That is why, it is important to recognize the dependencies between the structure of the casts and chemical composition changes connected with the addition of modifiers. Investigations concerning both the optimal chemical composition and production method of Zn–Al–Cu alloys modified by chosen rare-earth metals as well as the improved properties in comparison with traditional alloys and methods contribute to better understanding the mechanisms influencing the improvement of mechanical properties of the new developed alloys.