Method of Heat Treatment of a Metal Material

Abstract

A method of heat treatment of a metal material is disclosed. The method of heat treatment includes heating the metal material to a first temperature through a heating fixture, and reducing the first temperature of the metal material to a second temperature through a cooling apparatus performing a fast cooling operation. The fast cooling operation has a high cooling speed of 80° C./sec to 200° C./sec. As such, the processed metal material can have the required mechanical properties.

What is claimed is: 
     
         1 . A method of heat treatment of a metal material, comprising:
 heating the metal material to a first temperature through a heating fixture; and   reducing the first temperature of the metal material to a second temperature through a cooling apparatus performing a fast cooling operation, wherein the fast cooling operation has a high cooling speed of 80° C./sec to 200° C./sec.   
     
     
         2 . The method of heat treatment of the metal material as claimed in  claim 1 , wherein the fast cooling operation comprises spraying a coolant to the metal material through a spraying unit of the cooling apparatus. 
     
     
         3 . The method of heat treatment of the metal material as claimed in  claim 2 , wherein the fast cooling operation comprises spraying the coolant to the metal material with a high speed ejection flow of 60 L/min to 1000 L/min. 
     
     
         4 . The method of heat treatment of the metal material as claimed in  claim 2 , wherein the coolant applies a high speed ejection pressure to the metal material at the instant the coolant hits the metal material, and wherein the high speed ejection pressure is 70-300 bars. 
     
     
         5 . The method of heat treatment of the metal material as claimed in  claim 1 , further comprising reducing the second temperature of the metal material to a third temperature through the cooling apparatus performing a slow cooling operation, wherein the slow cooling operation has a slow cooling speed of 50° C./sec to 80° C./sec. 
     
     
         6 . The method of heat treatment of the metal material as claimed in  claim 5 , wherein the slow cooling operation comprises spraying a coolant to the metal material through a spraying unit of the cooling apparatus. 
     
     
         7 . The method of heat treatment of the metal material as claimed in  claim 6 , wherein the slow cooling operation comprises spraying the coolant to the metal material with a low speed ejection flow of 20 L/min to 60 L/min. 
     
     
         8 . The method of heat treatment of the metal material as claimed in  claim 6 , wherein the coolant applies a low speed ejection pressure to the metal material at the instant the coolant hits the metal material, and wherein the low speed ejection pressure is 30-70 bars. 
     
     
         9 . The method of heat treatment of the metal material as claimed in  claim 1 , further comprising convoying the metal material in a convoying direction through a convoying unit of the cooling apparatus. 
     
     
         10 . The method of heat treatment of the metal material as claimed in  claim 9 , wherein the cooling apparatus comprises a spraying unit spraying a coolant to the metal material in a spraying direction, and wherein an angle between the convoying direction and the spraying direction is between 15° and 90°. 
     
     
         11 . The method of heat treatment of the metal material as claimed in  claim 10 , wherein the angle is 45°. 
     
     
         12 . The method of heat treatment of the metal material as claimed in  claim 9 , further comprising rotating the metal material about an axle parallel to the convoying direction during the convoying of the metal material.