Shots made from zinc-based alloy

Abstract

Shots made from a zinc-based alloy is provided, wherein no risk for explosion caused by powder dusts exists. They achieve a high performance in deflashing and grinding and cleaning by shot blasting and a high ability to create a high compressive residual stress. The lost amounts of them by shooting are small. The shots are made from a zinc-based alloy that contains three components that include A1 of 0.5 to 6.5 mass % and Cu of 0.5 to 4.5 mass % as additional elements, or that contains four components that further include Mg of 0.01 to 0.2 mass % as additional elements, wherein the ratio of the mass of A1 to Cu (A1/Cu) is 1.0 to 13.0, wherein the total amount of A1 and Cu (A1+Cu) is 1.5 to 10.5 mass %, and wherein the Vickers hardness of the shots is 90 to 190 HV.

1 . Shots made from a zinc-based alloy that contains three components that include Al of 0.5 to 6.5 mass % and Cu of 0.5 to 4.5 mass % as additive elements,
 wherein a ratio of the mass of the Al to Cu (Al/Cu) is 1.0 to 13.0, wherein a total amount of the Al and Cu is 1.5 to 10.5 mass %, and wherein a Vickers hardness of the shots is 90 to 190 HV0.05.   
     
     
         2 . The shots made from a zinc-based alloy of  claim 1 , wherein a total amount of elements other than the three components (non-essential elements) is 0.5 mass % or less, and wherein an amount of Fe is 0.3 mass % or less. 
     
     
         3 . The shots made from a zinc-based alloy of  claim 1  or  2 , wherein a purity of both the Al and Cu is 99.9 mass % or more, and wherein the total amount of the non-essential elements is 0.02 mass % or less. 
     
     
         4 . The shots made from a zinc-based alloy of  claim 1 , wherein the shots are used for a surface treatment of a workpiece that is made from a nonferrous material that is selected from a group of an aluminum-based alloy, a zinc-based alloy, and a magnesium-based alloy. 
     
     
         5 . The shots made from a zinc-based alloy of  claim 4 , wherein the alloy contains three components that include Al of 3.0 to 6.0 mass % and Cu of 1.0 to 3.0 mass % as additive elements. 
     
     
         6 . The shots made from a zinc-based alloy of  claim 1 , wherein the shots are used for a surface treatment for deflashing of a workpiece that is made from a nonferrous material that is selected from a group of an aluminum-based alloy, a zinc-based alloy, and a magnesium-based alloy, and wherein a Vickers hardness of the shots is 130 to 154 HV0.05. 
     
     
         7 . Shots made from a zinc-based alloy that contains four components that include Al of 0.5 to 6.5 mass %, Cu of 0.5 to 4.5 mass %, and Mg of 0.01 to 0.2 mass % as additive elements,
 wherein a ratio of the mass of the Al to Cu (Al/Cu) is 1.0 to 13.0, wherein a total amount of the Al and Cu is 1.5 to 8.0 mass %, and wherein a Vickers hardness of the shots is 90 to 190 HV0.05.   
     
     
         8 . The shots made from a zinc-based alloy of  claim 7 , wherein a total amount of non-essential elements that are other than the four components is 0.5 mass % or less, and wherein an amount of Fe is 0.3 mass % or less. 
     
     
         9 . The shots made from a zinc-based alloy of  claim 7  or  8 , wherein a purity of the Al, Cu, and Mg is 99.9 mass % or more, and wherein the total amount of the non-essential elements is 0.02 mass % or less. 
     
     
         10 . The shots made from a zinc-based alloy of  claim 7 , wherein the shots are used for a surface treatment of a workpiece that is made from a nonferrous material that is selected from a group of an aluminum-based alloy, a zinc-based alloy, and a magnesium-based alloy. 
     
     
         11 . The shots made from a zinc-based alloy of  claim 10 , wherein the alloy contains four components that include Al of 3.0 to 5.0 mass %, Cu of 1.0 to 3.0 mass %, and Mg of 0.01 to 0.2 mass % as additive elements. 
     
     
         12 . The shots made from a zinc-based alloy of  claim 7 , wherein the shots are used for a surface treatment for deflashing of a workpiece that is made from a nonferrous material that is selected from a group of an aluminum-based alloy, a zinc-based alloy, and a magnesium-based alloy, and wherein a Vickers hardness of the shots is 140 to 150 HV0.05. 
     
     
         13 . The shots made from a zinc-based alloy of  claim 7 , wherein the shots are used for a surface treatment as shot peening for a workpiece that is made from a nonferrous material that is selected from a group of an aluminum-based alloy, a zinc-based alloy, and a magnesium-based alloy, and wherein a Vickers hardness of the shots is 140 to 150 HV0.05. 
     
     
         14 . The shots made from a zinc-based alloy of  claim 1  or  7 , wherein a mean diameter of the shots is 0.1 to 3 mm. 
     
     
         15 . A method of manufacturing the shots made from a zinc-based alloy of  claim 1  or  7 , the method comprising the steps of:
 dropping molten metal into a cooling medium such as water; 
 solidifying and depositing the molten metal in the cooling medium; 
 drying spherical bodies that have been solidified and deposited; and 
 classifying the spherical bodies. 
 
     
     
         16 . A method of manufacturing the shots made from a zinc-based alloy of  claim 14 , the method comprising the steps of:
 dropping metal into a cooling medium such as water;   solidifying and depositing the molten metal in the cooling medium;   drying spherical bodies that have been solidified and deposited; and   classifying the spherical bodies.   
     
     
         17 . Shots made from a zinc-based alloy that are manufactured by the method of  claim 15 , wherein 60% of the shots have a/b at a range of 1.0 to 1.2, where “a” is a length of the spherical body in a longitudinal direction and “b” is a maximum diameter in a direction perpendicular to the longitudinal direction. 
     
     
         18 . Shots made from a zinc-based alloy that are manufactured by the method of  claim 16 , wherein 60% of the shots have a/b at a range of 1.0 to 1.2, where “a” is a length of the spherical body in a longitudinal direction and “b” is a maximum diameter in a direction perpendicular to the longitudinal direction. 
     
     
         19 . The shots made from a zinc-based alloy of  claim 7  or  12 , wherein a mean diameter of the shots is 0.3 to 2.0 mm. 
     
     
         20 . The shots made from a zinc-based alloy of  claim 14 , wherein a mean diameter of the shots is 0.3 to 2.0 mm. 
     
     
         21 . The shots made from a zinc-based alloy of  claim 17 , wherein a mean diameter of the shots is 0.3 to 2.0 mm. 
     
     
         22 . The shots made from a zinc-based alloy of  claim 18 , wherein a mean diameter of the shots is 0.3 to 2.0 mm. 
     
     
         23 . The shots made from a zinc-based alloy of  claim 19 , wherein a mean diameter of the shots is 0.3 to 0.6 mm. 
     
     
         24 . The shots made from a zinc-based alloy of  claim 20 , wherein a mean diameter of the shots is 0.3 to 0.6 mm. 
     
     
         25 . The shots made from a zinc-based alloy of  claim 21 , wherein a mean diameter of the shots is 0.3 to 0.6 mm. 
     
     
         26 . The shots made from a zinc-based alloy of  claim 22 , wherein a mean diameter of the shots is 0.3 to 0.6 mm.