Slip bands in metals

Slip bands or stretcher-strain marks are localized bands of <a href="/facts/Plastic_deformation/z1LEmkQX">plastic deformation</a> in metals experiencing stresses. Formation of slip bands indicates a concentrated unidirectional <a href="/facts/Slip_(materials_science)/P29xbKBu">slip</a> on certain planes causing a stress concentration. Typically, slip bands induce surface steps (e.g., roughness due <a href="/facts/Persistent_slip_bands/65QKqxzL">persistent slip bands</a> during <a href="/facts/Fatigue_(material)/zmJY8hMt">fatigue</a>) and a stress concentration which can be a crack nucleation site. Slip bands extend until impinged by a <a href="/facts/Grain_boundary/3r6klMTy">boundary</a>, and the generated stress from <a href="/facts/Dislocation/m1tkJYIq">dislocations</a> pile-up against that boundary will either stop or transmit the operating slip depending on its (mis)orientation.
Formation of slip bands under cyclic conditions is addressed as <a href="/facts/Slip_bands/65QKqxzL">persistent slip bands</a> (PSBs) where formation under monotonic condition is addressed as dislocation planar arrays (or simply slip-bands, see <a href="/facts/Slip_bands/65QKqxzL">Slip bands in the absence of cyclic loading</a> section). Slip-bands can be simply viewed as boundary sliding due to dislocation glide that lacks (the complexity of ) PSBs high plastic deformation localisation manifested by tongue- and ribbon-like extrusion. And, where <a href="/facts/Persistent_slip_bands/65QKqxzL">PSBs</a> normally studied with (effective) <a href="/facts/Burgers_vector/ACoBg3r9">Burgers vector</a> aligned with the extrusion plane because a PSB extends across the grain and exacerbates during fatigue; a monotonic slip-band has a Burger’s vector for propagation and another for plane extrusions both controlled by the conditions at the tip.

Slip bands in metals open-in-new

Slip bands in metals