Microstructures and electrochemical behaviors of as-cast magnesium alloys with enhanced compressive strengths and corrosion decomposition

Rapidly disintegrating alloys with enhanced compressive strengths and corrosion rates are prepared for fracturing parts in petroleum extraction. Extrusion casting is used to prepare Mg-xZn-Zr alloys by adjusting zinc content. Mechanical and electrochemical behaviors are investigated to evaluate the practicability as decomposable materials. Superficial topographies, compositions, phases, and distributions are also characterized to determine the dissociative mechanism. The results make clear that matrixes and secondary structures with reticulate shapes arise on surfaces. The material also possesses enhanced compressive strength to guarantee stabilization and pressure-holding ability among decomposition. Concurrently, with the increase of zinc content and decomposition time, galvanic corrosion aggravates resulting in gradually reduced corrosion potentials and accelerated decomposition rates. Rapid material dissolution mainly attributes to anode corrosion of matrixes, peeling of microparticles, and inferior tolerance of corrosive products to dissolution. Such work highlights potential applications of fracturing materials for ensuring rapid decomposition and guaranteeing stable stress tolerance.