Conformal cooling insert

Abstract

A cooling insert for a die, such as a distributor for a high pressure die casting assembly, and a method of manufacturing the cooling insert, is provided. The cooling insert can be formed of H13 tool steel and is manufactured using an investment casting process, for example, a process which uses a printed investment casting shell. The cooling insert includes complex cooling channels to improve cooling and reduce the duration of the casting process.

What is claimed is: 
     
         1 . A cooling insert for a die, comprising:
 a steel material presenting a surface and including at least one cooling channel; and   one cooling channel of said at least one cooling channel has a diameter and is located a distance from said surface equal to 1.5 times to 1.8 times said diameter of said cooling channel.   
     
     
         2 . The cooling insert of  claim 1 , wherein said at least one cooling channel includes a plurality of curves. 
     
     
         3 . The cooling insert of  claim 2 , wherein said at least one cooling channel includes at least ten curves. 
     
     
         4 . The cooling insert of  claim 1 , wherein said steel material presents a surface, one cooling channel of said at least one cooling channel includes a plurality of curves and a plurality of segments, and said segments are disposed parallel to one another and are located an equal distance from said surface. 
     
     
         5 . The cooling insert of  claim 1 , wherein said steel material includes chromium (Cr) in an amount of 4.75-5.50 weight percent (wt. %), molybdenum (Mo) in an amount of 1.10-1.75 wt. %, silicon (Si) in an amount of 0.80-1.20 wt. %, vanadium (V) in an amount of 0.80-1.20 wt. %, carbon (C) in an amount of 0.32-0.45 wt. %, manganese (Mn) in an amount of 0.20-0.50 wt. %, phosphorous in an amount up to 0.03 wt. %, sulfur in an amount up to 0.03 wt. %, and possibility impurities in an amount up to 0.2 wt. %, based on the total weight of said steel material. 
     
     
         6 . The cooling inset of  claim 5 , wherein said steel material includes the chromium (Cr) in an amount of 5.25 weight percent (wt. %), the molybdenum (Mo) in an amount of 1.35 wt. %, the silicon (Si) in an amount of 1.00 wt. %, the vanadium (V) in an amount of 1.00 wt. %, the carbon (C) in an amount of 0.40 wt. %, and the manganese (Mn) in an amount of 0.40 wt. %, based on the total weight of said steel material. 
     
     
         7 . The cooling inset of  claim 5 , wherein said steel material has a hardness of 380 to 480 HV10 and a yield strength of 900 to 1300 MPa. 
     
     
         8 . The cooling insert of  claim 5 , wherein said steel material has a density of 7.80 g/cm 3  to 7.0 g/cm 3  at 20° C.; ultimate tensile strength (UTS) of 1000 MPa to 1590 MPa; elongation of 15 to 40%; yield strength of 900 to 1300 MPa; Young's Modulus of 206 GPa to 190 GPa from 70° C. to 800° C.; thermal expansion at 20° C. to 100° C. of 10.4 to 12.5*10 −6 /K; and heat conductivity from 80 to 800° C. of 17.6 to 25.0 W/mK. 
     
     
         9 . The cooling insert of  claim 8 , wherein said density is 17.3 g/cm 3  at 20° C.; said elongation is 40%; said yield strength is 1200 MPa; said Young's Modulus is 210 GPa from 70° C. to 800° C.; said thermal expansion is 11*10 −6 /K at 20° C. to 100° C.; and said heat conductivity from 80 to 800° C. is 23 W/mK. 
     
     
         10 . An apparatus for high pressure die casting (HPDC) parts formed of aluminum or aluminum alloy, comprising:
 a die including a surface presenting cavity for containing molten aluminum or aluminum alloy; and   said cooling insert of  claim 1  disposed along said surface.   
     
     
         11 . A method of high pressure die casting a part comprising the steps of: disposing the cooling insert of  claim 1  along a surface of a casting assembly, the surface and the cooling insert presenting a cavity for containing molten metal; and conveying cooling fluid through the at least one cooling channel of the cooling insert while molten metal is disposed in the cavity. 
     
     
         12 . A method of manufacturing a cooling insert for use in a high pressure die casting assembly, comprising the steps of:
 investment casting an iron-based material to form a cooling insert having at least one cooling channel.   
     
     
         13 . The method of  claim 12 , wherein the investment casting step includes forming a wax pattern by injecting wax into a prefabricated die;
 immersing the wax pattern a ceramic slurry;   drying the ceramic slurry on the wax pattern;   repeating the immersing and drying steps until a solid ceramic shell is formed on the wax pattern;   heating the wax and ceramic shell to melt the wax off of the ceramic shell;   disposing the ceramic shell in a container of heated sand;   filling the container and surrounding the ceramic shell with the iron-based material, the iron-based material being molten;   solidifying and cooling the molten iron-based material on the ceramic shell to form the cooling insert of the iron-based material; and   removing the ceramic shell from the cooling insert.   
     
     
         14 . The method of  claim 13 , wherein the ceramic shell has a thickness of 6 mm to 9 mm and the cooling insert includes a plurality of curves. 
     
     
         15 . The method of  claim 12 , wherein the at least one cooling channel includes a plurality of curves, the iron-based material presents a surface, and one cooling channel of the at least one cooling channel has a diameter and is located a distance from the surface equal to 1.5 times to 1.8 times the diameter of the cooling channel. 
     
     
         16 . The method of  claim 12 , wherein the iron-based material is a steel material, the steel material includes chromium (Cr) in an amount of 4.75-5.50 weight percent (wt. %), molybdenum (Mo) in an amount of 1.10-1.75 wt. %, silicon (Si) in an amount of 0.80-1.20 wt. %, vanadium (V) in an amount of 0.80-1.20 wt. %, carbon (C) in an amount of 0.32-0.45 wt. %, manganese (Mn) in an amount of 0.20-0.50 wt. %, phosphorous in an amount up to 0.03 wt. %, sulfur in an amount up to 0.03 wt. %, and possibility impurities in an amount up to 0.2 wt. %, based on the total weight of the steel material; and the steel material has a hardness of 380 to 480 HV10 and a yield strength of 900 to 1300 MPa after the investment casting step.