Simultaneous achievement of high electromagnetic shielding effectiveness (X-band) and strength in Mg-Li-Zn-Gd/MWCNTs composite

•Mg-9Li-3Zn-0.5Gd/MWCNTs composite was prepared by the method of heat treatment+EPD+ARB.•The high density dislocations introduced by ARB process promoted the dynamic precipitation of the nano-scale MgZn2 phases.•The added MWCNTs could induce the precipitation of fine and dense ultrafine nanoparticle W-phases.•Simultaneous achievement of high EMI SE (X-band) and strength in Mg-9Li-3Zn-0.5Gd/MWCNTs composite.