A method of manufacturing a dissolvable article comprises forming a liquid-solid mixture comprising secondary particles homogeneously dispersed in a molten metallic matrix material; disposing the liquid-solid mixture in a mold; agitating the liquid-solid mixture in the mold; and molding the liquid-solid mixture under agitation to form a dissolvable article, wherein the secondary particles and the metallic matrix material form a plurality of micro- or nano-sized galvanic cells in the dissolvable article.