Low-density high-toughness alloy and the fabrication method thereof

Abstract

The present invention discloses a low-density high-toughness alloy and the fabrication method thereof. The alloy of the present invention consists essentially of: by weight percent, equal to or greater than 23% but lower than or equal to 33% manganese, equal to or greater than 8.1% but lower than or equal to 9.8% aluminum, equal to or greater than 3% but lower than or equal to 5.0% chromium, equal to or greater than 0.6% but lower than or equal to 1.2% carbon, equal to or greater than 0.1% but lower than or equal to 0.24% silicon and the balance of iron. The golf-club head made from the abovementioned alloy can obtain superior elongation, strength, damping capacity, and corrosion resistance even without any heat treatment, or any hot/cold working, such as forging and rolling; therefore, the fabrication cost thereof can be obviously reduced.

1 . A low-density high-toughness alloy, comprising: equal to or greater than 23 wt. % but lower than or equal to 33 wt. % manganese, equal to or greater than 8.1 wt. % but lower than or equal to 9.8 wt. % aluminum, equal to or greater than 3 wt. % but lower than or equal to 5.0 wt. % chromium, equal to or greater than 0.6 wt. % but lower than or equal to 1.2 wt. % carbon, equal to or greater than 0.1 wt. % but lower than or equal to 0.24 wt. % silicon, and the balance of iron. 
   
   
       2 . The low-density high-toughness alloy according to  claim 1 , further comprising up to 1.5 wt. % molybdenum. 
   
   
       3 . The low-density high-toughness alloy according to  claim 1 , having a density ranging from 6.6 to 6.9 g/cm 3 , an elongation ranging from 30 to 60%, and a tensile strength ranging from 100 to 135 ksi. 
   
   
       4 . A fabrication method of a low-density high-toughness alloy, comprising melting a raw material, which comprises: equal to or greater than 23 wt. % but lower than or equal to 33 wt. % manganese, equal to or greater than 8.1 wt. % but lower than or equal to 9.8 wt. % aluminum, equal to or greater than 3 wt. % but lower than or equal to 5.0 wt. % chromium, equal to or greater than 0.6 wt. % but lower than or equal to 1.2 wt. % carbon, equal to or greater than 0.1 wt. % but lower than or equal to 0.24 wt. % silicon, and the balance of iron;
 pouring said raw material into shell molds having spiral runner and pre-heated; and   de-casting said raw material from said shell molds.   
   
   
       5 . The fabrication method of a low-density high-toughness alloy according to  claim 4 , wherein said raw material further comprises up to 1.5 wt. % molybdenum. 
   
   
       6 . The fabrication method of a low-density high-toughness alloy according to  claim 4 , further comprising a step of heat-treating said alloy at the temperature ranging from 950 to 1200° C. for the duration ranging from 1 to 3 hours. 
   
   
       7 . The fabrication method of a low-density high-toughness alloy according to  claim 4 , wherein said raw material is melted at the atmosphere, at vacuum, or at a reducing atmosphere. 
   
   
       8 . The fabrication method of a low-density high-toughness alloy according to  claim 4 , wherein said alloy has a density ranging from 6.6 to 6.9 g/cm 3 , an elongation ranging from 30 to 60%, and a tensile strength ranging from 100 to 135 ksi.