Investigation of Micromechanical Properties and Tribological Behavior of WE43 Magnesium Alloy after Deep Cryogenic Treatment Combined with Precipitation Hardening

Abstract

This study investigated the micromechanical and tribological properties of WE43 alloy (Mg-Y-Nd-Zr) alloy subjected to cryogenic treatment and precipitation hardening. Microindentation tests were carried out in the range of load from 100 to 1000 mN. The introduction of deep cryogenic treatment (DCT) was shown to increase hardness and Young’s modulus, and reduce the total indentation work. As the load set during the tests increased, a gradual decrease in the measured values was observed, indicating a significant relationship between the indent size and the value of the measured parameters. Cryogenic treatment used in conjunction with precipitation hardening (after solutioning and after aging) reduces the tribological wear of the alloy. Tests have shown an almost twofold reduction in the area of the wear trace and in the volumetric wear of the alloy, as well as a more than twofold reduction in linear wear, with relatively small fluctuations in the coefficient of friction. Abrasion was the main mechanism of wear. Areas where microcutting, adhesion and plastic deformation occurred were also observed. The results indicate the significant effectiveness of the applied heat treatment in improving the service life of the WE43 alloy containing rare earth metals.

Microstructural and Mechanical Properties of a Heat-Treated EV31A Magnesium Alloy Fabricated Using the Stir-Casting Process

“…REE-Mg has been found to have superior mechanical and corrosion resistance compared to other Mg alloys, according to [20]. The service life of a Mg alloy can be extended through additional heat treatment by varying the temperature and holding time [21]. It has also been reported that alloying Nd and Gd increases Mg castability and precipitate strengthening.…”

The Effect of Changes in the Aging Temperature Combined with Deep Cryogenic Treatment on the Structure, Phase Composition, and Micromechanical Properties of the WE43 Magnesium Alloy

“…and Fe and Ni in amounts exceeding 0.005% wt. are the most harmful impurities affecting the corrosion resistance and plasticity of the alloy) [11], optimization of its chemical composition [12][13][14], preparation methods [2], heat treatment [15][16][17][18][19][20], plastic forming [21,22], and surface modification, including chromium plating, TiN, CrN, AlN aluminum, and titanium coatings; and coatings made of calciumphosphate compounds (Ca-P) to obtain better mechanical, corrosion, and tribological properties [23].…”