Transactions of Nonferrous Metals Society of China (中国有色金属学报)•2026•DOI: 10.1016/S1003-6326(26)67058-6
Twin-roll casting (TRC) Mg−3Al−1Sn−0.5Ca−0.2Mn (ATXM) alloys exhibit limited deformation resistance and inadequate corrosion performance, constraining their commercial deployment. This study integrates rare earth (RE) microalloying (Sm, Ce, or Y at 0.1 wt.%) with rolling to address the strength–plasticity–corrosion trilemma. Rolling reduces grain size from ~50 μm to below 5 μm and transforms Al8Mn5 secondary phases into Al8Mn4RE, modifying phase composition, dimension, and spatial arrangement. The rolled ATXM-0.1Y alloy achieves a yield strength of 238 MPa, tensile strength of 305 MPa, and elongation of 23%, coupled with a corrosion rate of approximately 1.7 mm/a—an ~80% reduction relative to TRC ATXM. Sm and Ce additions yield strengths of 238 and 232 MPa, elongations of 18% and 17%, and corrosion rates of 3.4 and 2.9 mm/a, respectively. Strengthening mechanisms are attributed to fine-grain and Orowan strengthening, while corrosion mitigation arises from reduced individual galvanic corrosion and enhanced protective corrosion product film quality. The work establishes a screening protocol for RE elements and processing parameters to synergistically improve mechanical and corrosion properties, facilitating commercial adoption of Mg alloys.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.08.016
Chalcopyrite is often intergrown with talc, which, after grinding, forms ultrafine particles (<10 μm) that readily coat chalcopyrite surfaces, hindering flotation and causing significant losses in tailings. This study evaluates polyvinyl acetate (PVAc), a thermoplastic polymer, as a selective flocculant to enhance reverse flotation separation of chalcopyrite from ultrafine talc. Flotation tests showed that at a PVAc dosage of 40 mg/L, talc can be effectively and selectively removed, enabling efficient separation. Laser particle size analysis and scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) confirmed that PVAc promotes selective talc aggregation without affecting chalcopyrite. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that hydrogen bonding between PVAc ester groups and surface hydroxyls on talc drives the flocculation, while chalcopyrite lacks suitable binding sites. PVAc adsorption also enhances talc hydrophobicity. Furthermore, particle-bubble coverage angle measurements and extended Derjaguin-Landau-Verwey-Overbeek (DLVO) theory theoretical calculations demonstrated that PVAc-induced flocculation increases attractive interactions between talc and bubbles, shifting the total interaction energy from repulsive to attractive and promoting bubble-particle attachment. This study clarifies the selective adsorption and flocculation mechanisms of PVAc and reveals the coupling of flocculation and flotation of ultrafine talc from a particle-bubble capture perspective, while expanding the potential of ester-based polymers for ultrafine mineral recovery.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.08.016
Chalcopyrite is often intergrown with talc, which, after grinding, forms ultrafine particles (<10 lm) that readily coat chalcopyrite surfaces, hindering flotation and causing significant losses in tailings. This study evaluates polyvinyl acetate (PVAc), a thermoplastic polymer, as a selective flocculant to enhance reverse flotation separation of chalcopyrite from ultrafine talc. Flotation tests showed that at a PVAc dosage of 40 mg/L, talc can be effectively and selectively removed, enabling efficient separation. Laser particle size analysis and scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) confirmed that PVAc promotes selective talc aggregation without affecting chalcopyrite. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that hydrogen bonding between PVAc ester groups and surface hydroxyls on talc drives the flocculation, while chalcopyrite lacks suitable binding sites. PVAc adsorption also enhances talc hydrophobicity. Furthermore, particle-bubble coverage angle measurements and extended Derjaguin-Landau-Verwey-Overbeek (DLVO) theory theoretical calculations demonstrated that PVAc-induced flocculation increases attractive interactions between talc and bubbles, shifting the total interaction energy from repulsive to attractive and promoting bubble-particle attachment. This study clarifies the selective adsorption and flocculation mechanisms of PVAc and reveals the coupling of flocculation and flotation of ultrafine talc from a particle-bubble capture perspective, while expanding the potential of ester-based polymers for ultrafine mineral recovery.