What are the differences between malleable and ductile metals??
Most metals that are ductile are also malleable, and vice versa, although there are some that would be considered exceptions to this. Ductility, as it is typically defined and reported as a property, refers to a metal’s capacity for elongation and/or reduction of cross-sectional area under uniaxial tension, i.e., pulling in one direction. (As a side note, “formability” is the capacity for plastic deformation under biaxial tension, i.e., pulling in two directions at once.) It should be noted that this so-called “property” is not independent of specimen geometry, mainly because of a tensile instability known as “necking,” which localizes plastic deformation over a small portion of the specified gage length. Malleability, on the other hand, refers to a metal’s capacity for thinning and lateral expansion under uniaxial compression, i.e., “flattening.” This property is even less rigorously defined than ductility, and is probably more accurately described as a fabrication characteristic. Bot
