a method and apparatus for coldworking holes using rotational mandrel . the apparatus uses a tubular seamless sleeve made of shape memory alloys having a superelasticity property , a mandrel having major and minor diameter portions , an end - cap to seat and restrain axial and rotational motion of said sleeve . the preferred coldworking operation includes the steps of placing the sleeve firmly between the end - cap and the adapting - spacer which are carried on a mandrel pulling means , passing forward the major diameter portion of the mandrel through the sleeve whose diameter is therefore elastically expanded and thereafter shrinks , inserting the sleeve together with the mandrel into said hole , placing the end - cap against the workpiece , retracting while rotating the mandrel backward through and out of the sleeve ; thereby expanding the sleeve wall against the hole bore and exerting radial outward force on the sleeve which in turn transmits the coldworking force to the hole bore and plastically expand said hole ; thereafter the sleeve diameter shrinking to a smaller size to ease the removal of the sleeve out of the hole . the sleeve is reusable due to the superelasticity property of shape memory alloys .