an implantable medical device is provided that degrades upon contact with body fluids so as to limit its residence time within the body . the device is formed of a porous corrodible metal to simultaneously provide high strength and an accelerated corrosion rate . the corrosion rate of a device formed of metal subject to self - dissolution or of a combination of metals subject to galvanic corrosion is accelerated by its porous structure . coating the corrodible metallic device with a degradable polymer serves to delay the onset of corrosion of the underlying metallic structure .