Microstructure and Mechanical Behaviors of the New LAZ1151 Mg-Li Alloy

Abstract

This research studies a brand new Magnesium Lithium Alloy, LAZ1151, with trace Sc additions. The mechanical properties and microstructures of the as-cast and alloys after three and six month aging were observed and analyzed. Microstructure and XRD confirms the existence of α phase precipitates (Mg rich) in both as-cast and aging specimens of the alloy. Grain growth was observed in the alloy after room temperature aging. The tensile strength of the as-cast LAZ1151 is 147 MPa; the value is decreased to 135 MPa after six month aging, showing typical room temperature softening. Strengthening via the use of cold rolling was tried; a maximum tensile strength of 180 MPa was achieved after 90% rolling reduction, which is mainly due to strain hardening.

Strengthening Mechanisms of Magnesium-Lithium Based Alloys and Composites

“…The yield strength and tensile strength increased by 65.32% and 77.34%, respectively, along with enhanced alloy toughness. Cheng et al [11] in their research study developed a mechanism for strengthening new LAZ1151 Mg-Li alloy by use of cold rolling process (Figure 9). Strengthening effect is initiated through reduction of dislocation movement distance by refining the grain size (227 m→147 m).…”

“…When external energies were induced in to the lattice, the strain energy in the -phase gets eliminated because the magnesium atoms form strong -phase composite. Recent study research by Song et al shows -phase alloys of Mg (11)(12)(13)(14)Li-Al possessing greater capacity for natural or artificial age strength hardening. The maximum hardening takes place only during aging process and correlates with the -phase precipitation taking place at room temperature.…”

Microstructure and mechanical properties of LA51 and LA51–0.5Y alloys with different accumulated strains and rolling temperatures

“…Accumulated strain and rolling temperature are two important factors during the rolling process. As reported by Cheng et al [9], with the rolling reduction of the LAZ1151 alloy changing from 30% to 90%, the average grain size reduces from 227 μm to 147 μm, and the maximum tensile strength increases from 159.57 MPa to 180.17 MPa due to strain hardening. Mackenzie and Pekguleryuz [10] investigated the texture variation of Mg-3Li-3Al-1Zn alloy under different rolling temperatures.…”

Production of Mg-Li alloys by aluminothermic vacuum reduction

“…The effect of aluminum addition on the reduction ratio of MgO and Li 2 O is shown in Figure 5, where zero excess aluminum refers to the stoichiometry quantity given by Eq. (5).…”

“…They are therefore known as superlight alloys [1][2][3]. Because of their specific strength, rigidity, and good damping capacity, Mg-Li alloys have been widely explored in applications in the aircraft, electronics, and communication industries [4,5].…”