Method of hot-shaping and hardening a steel workpiece

Abstract

A method of making a shaped and hardened steel part has the steps of sequentially heating a steel plate entirely above the AC 3 temperature, cooling specific regions of the heated plate without hardening the specific regions, and then engaging the heated plate with the cooled regions in a cool deforming tool with the specific regions out of contact with the deforming tool. This cools the plate where it contacts the tool and deforms the plate with the tool at the specific regions and both cooling and hardening the plate by contact with the tool.

1 . A method of making a shaped and hardened steel part, the method comprising the steps of sequentially:
 heating a steel plate entirely above the AC 3  temperature;   cooling specific regions of the heated plate without hardening the specific regions;   engaging the heated plate with the cooled regions in a cool deforming tool with the specific regions out of contact with the deforming tool and cooling the plate where it contacts the tool; and   deforming the plate with the tool at the specific regions and both cooling and hardening the plate by contact with the tool.   
   
   
       2 . The shaping and hardening method defined in  claim 1  wherein the specific regions are cooled by engagement with a cool block. 
   
   
       3 . The shaping and hardening method defined in  claim 1  wherein the specific regions are cooled by blowing cool gas against them. 
   
   
       4 . The shaping and hardening method defined in  claim 3  wherein the deforming tool is one half of a two-part mold and the specific regions are cooled before the other half of the mold is closed over the workpiece. 
   
   
       5 . A press for shaping and hardening a steel-plate workpiece that has been heated above the AC 3  temperature, the press comprising:
 a pair of cool mold halves closable on the workpiece, engageable with regions of the workpiece, and not engageable with specific other regions of the workpiece; and   means for cooling the specific regions without hardening them prior to closing of the workpiece.   
   
   
       6 . The press defined in  claim 5  wherein the means for cooling including cool-gas nozzles directed at the specific regions.