Fig. 1 Inverse pole figure (IPF) coloring maps, {0001} pole figures and distribution histograms of the grain size for a as-rolled AZ31, b as-extruded Mg3Y sheets

Fig. 2 Schematic illustration on the fabrication of AZ31/Mg3Y composite by ARB

Fig. 3 Tensile engineering stress-strain curves of the AZ31 sheet and the extruded Mg3Y sheet

Fig. 4 a Microstructure and chemical composition distribution in the as-rolled AZ31/Mg3Y composite, b high magnification BSE images for the interface layer

Fig. 5 Microstructure evolution in the interface layer of the AZ31/Mg3Y composite after annealing for different time: a 1 h, b 2 h, c 4 h, d 8 h, e 16 h, f 32 h

Fig. 6 a Thickness of the interface layer, volume percent of the interface layer in AZ31/Mg3Y composite and precipitates in interface layer after annealing at 300 °C for various time, b XRD pattern of the interface layer

Fig. 7 EBSD coloring maps and corresponding pole figures of AZ31/AZ31 sheets annealing at 300 °C for a 1 h, b 2 h, and AZ31/Mg3Y composite annealing at 300 °C for c 8 h, d 16 h, e 32 h

Fig. 8 Average grain size of AZ31/AZ31 sheet, the AZ31 layer and the Mg3Y layer in the AZ31/Mg3Y composite after annealing at 300 °C for 0-32 h (The recrystallization degree of the Mg3Y layer is too low to calculate its grain size when holding time is less than 8 h)

Fig. 9 Effect of the annealing time at 300 °C on the micro-hardness of different layers in AZ31/AZ31 and AZ31/Mg3Y composites

Fig. 10 Tensile properties of the AZ31/AZ31sheets and AZ31/Mg3Y LMCs after annealing at 300 °C for different time a, b engineering stress-strain curves, c yield strength, d fracture elongation

Fig. 11 Comparison of the tensile property of AZ31/Mg3Y composites in this work with other Mg-RE alloys (Mg-7Li-3Y [34], Mg3Y [35], LAZ832-0.5Nd-3RE [36], LAZ532-1.5RE [37], Mg-2Gd-0.5Mn [38], Mg-3Sm-0.5Zn-0.5Zr [39], Mg-2Gd [40], Mg1.6La1Ce0.5Gd [41])

Fig. 12 Morphologies near the fracture of the annealed AZ31/Mg3Y composites after tensile test: a A1, b A2, c A4, d A8, e A16, f A32

Fig. 13 a Fitting curve between the microhardness and the yield strength, b experimental and calculated yield strengths of the AZ31/Mg3Y composite

Fig. 14 GND distribution maps in the AZ31 layer of a, c AZ31/Mg3Y composite, b, d AZ31/AZ31 sheet before and after tension

Fig. 15 Histogram of GNDs density in the AZ31 layer of a, c AZ31/Mg3Y composite, b, d AZ31/AZ31 sheet before and after tension

Fig. 16 GNDs density distribution from the interface to the center of the AZ31 layer in a AZ31 layer of AZ31/Mg3Y composite, b AZ31/AZ31 sheet