Abstract
Microtwins produced by mechanical finishing in thin film of 18-8 stainless steel and α-brass of (110) orientation were observed by transmission electron microscopy. Secondary microtwins were sometimes produced from primary twins by small angle rotation round the primary twin axis. The mechanism of the microtwins are considered to be deformation twinning, leading to the conclusion that abrasion even under light load produces heavy plastic deformation in a superficial layer disturbed mechanically, which causes superficial work hardening.
