High frequency heat treatment material and method of manufacturing gear using the same

Abstract

The present invention relates to a high frequency heat treatment material and a method for manufacturing a gear using the same. According to the present invention, the high frequency heat treatment material is made of 0.50 to 0.55 wt % of carbon (C), 0.30 to 0.50 wt % of silicon (Si), 0.35 to 0.55 wt % of manganese (Mn), 0.30 wt % or less of copper (Cu), 0.25 wt % or less of nickel (Ni), 0.25 wt % or less of chromium (Cr), 0.35 to 0.45 wt % of molybdenum (Mo), 0.002 to 0.004 wt % of boron (B), 0.025 to 0.045 wt % of aluminum (Al), and the balance of Fe, and has stable deformation and physical properties equivalent to carburization heat treatment. Therefore, according to the present invention, it is possible to obtain a gear having high surface strength and hardness by machining a medium carbon steel.

What is claimed is: 
     
         1 . A high frequency heat treatment material, wherein the high frequency heat treatment material is made of 0.50 to 0.55 wt % of carbon (C), 0.30 to 0.50 wt % of silicon (Si), 0.35 to 0.55 wt % of manganese (Mn), 0.30 wt % or less of copper (Cu), 0.25 wt % or less of nickel (Ni), 0.25 wt % or less of chromium (Cr), 0.35 to 0.45 wt % of molybdenum (Mo), 0.002 to 0.004 wt % of boron (B), 0.025 to 0.045 wt % of aluminum (Al), and the balance of Fe, and has stable deformation and physical properties equivalent to carburization heat treatment. 
     
     
         2 . A method for manufacturing a gear using a high frequency heat treatment material, comprising:
 performing hot forging on a material, which is made of 0.50 to 0.55 wt % of carbon (C), 0.30 to 0.50 wt % of silicon (Si), 0.35 to 0.55 wt % of manganese (Mn), 0.30 wt % or less of copper (Cu), 0.25 wt % or less of nickel (Ni), 0.25 wt % or less of chromium (Cr), 0.35 to 0.45 wt % of molybdenum (Mo), 0.002 to 0.004 wt % of boron (B), 0.025 to 0.045 wt % of aluminum (Al), and the balance of Fe, at 1200° C. (S 100 );   grinding the material in a form meeting gears (S 200 );   performing soft teeth pitch machining to machine a teeth pitch on the ground gears (S 300 );   performing high frequency contour heat treating on the teeth pitch formed on the gears (S 400 ); and   performing hard machining to finish the gears which suffer from the high frequency contour heat treatment (S 500 ).   
     
     
         3 . The method of  claim 2 , wherein in the high frequency contour heat treating (S 400 ), heat treatment is performed at 850 to 940° C. for 15 minutes.