Patent ID: 7378622

Claim:
A method for electromagnetic pulse surface treatment of a work piece ( 20 ) supported by a fixture ( 10 ), wherein the work piece ( 20 ) has a bearing surface ( 22 ), a working surface ( 24 ), and a thickness ( 28 ), separating the bearing surface ( 22 ) and the working surface ( 24 ), the method comprising the steps of: (A) mounting the work piece ( 20 ) to the fixture ( 10 ); (B) placing an electromagnetic pulse tool ( 100 ), having a tool face ( 110 ) and a tool axis ( 120 ), at a working distance ( 130 ) from the working surface ( 24 ), wherein the tool face ( 110 ) has a tool face perimeter ( 112 ); and (C) energizing an electromagnetic pulse generator ( 200 ) to generate a current pulse, such that the current pulse propagates through the electromagnetic pulse tool ( 100 ) and the electromagnetic pulse tool ( 100 ) forms an electromagnetic pulse, the electromagnetic pulse strikes the working surface ( 24 ) forming both an indentation ( 300 ) and a residual compressive stress layer ( 600 ) in the working surface ( 24 ), wherein the electromagnetic pulse produces substantially no stress change in the bearing surface ( 22 ), and wherein the indentation ( 300 ) has: (i) an indentation perimeter ( 310 ); (ii) an indentation sidewall ( 330 ); (iii) an indentation transition region ( 320 ) that extends from the indentation perimeter ( 310 ) to the indentation sidewall ( 330 ), wherein the indentation transition region ( 320 ) is described by an indentation transition radius ( 322 ); (iv) an impact region ( 350 ) formed at an indentation depth ( 360 ) from an untreated surface ( 26 ) of the work piece ( 20 ), wherein the thickness ( 28 ) is greater than a compressed thickness ( 34 ), measured from the impact region ( 350 ) to the bearing surface ( 22 ); and (v) an impact transition region ( 340 ) that extends from the indentation sidewall ( 330 ) to the impact region ( 350 ), wherein the impact transition region ( 340 ) is described by an impact transition region radius ( 342 ), and wherein the indentation transition region ( 320 ), the indentation sidewall ( 330 ), and the impact transition region ( 340 ) are curvilinear.