Method of refining alloy crystal grain by hydrogen treatment

Abstract

A technology for refining the crystal grains of alloy whose main constituents are elements exhibiting weak affinity with hydrogen. With respect to the alloy whose main constituents are elements exhibiting weak affinity with hydrogen in which an element exhibiting strong affinity with hydrogen is contained, resulting from attaining of presence of an element exhibiting strong affinity with hydrogen in an alloy whose main constituents are elements exhibiting weak affinity with hydrogen, any crystal grains of the alloy can be super-atomized by subjecting the alloy to heat treatment involving hydrogen absorption and release, thereby realizing super-high strength thereof. Thus, the properties of the alloy can be improved and enhanced.

1 . A method of refining crystal grains of an alloy whose main constituent(s) is(are) an element(s) weak in affinity for hydrogen and which contains an element strong in affinity for hydrogen which method is characterized in that the alloy is subjected to hydrogen absorption/desorption heat treatment involving causing the alloy to occlude hydrogen within a temperature range of 0° C. to 0.8 T M  (T M  being the melting point of the metal or alloy as expressed in terms of absolute temperature) and then allowing the hydrogen to be released within a temperature range of 0° C. to 0.8 T M .  
   
   
       2 . A method of refining crystal grains of an alloy as set forth in  claim 1  which is characterized in that the alloy system to which the hydrogen absorption/desorption heat treatment is applicable is mainly an alloy comprising, as an element(s) weak in affinity for hydrogen, an element or a range of elements selected from elements of the groups 6-10 of the periodic table of the elements (except for Pd), typically Cr, Mn, Fe, Co and Ni, and elements of the groups 11-15 of the periodic table of the elements, typically Cu, Ag, Au, Zn and Al.  
   
   
       3 . A method of refining crystal grains of an alloy as set forth in  claim 1  which is characterized in that the alloy system to which the hydrogen absorption/desorption heat treatment is applicable contains at least one metal strong in affinity for hydrogen as selected from the group consisting of alkali metals such as Li and Na, alkaline earth metals such as Mg and Ca, rare earth metals such as La and Ce, transition metals of the groups 3-5 of the periodic table of the elements, typically Ti and V, and Pd.  
   
   
       4 . A crystal grain refined alloy characterized in that it is an alloy whose main constituent(s) is(are) an element(s) weak in affinity for hydrogen and which contains an element strong in affinity for hydrogen and is obtained by subjecting said alloy to hydrogen absorption/desorption heat treatment involving causing the alloy to occlude hydrogen within a temperature range of 0° C. to 0.8 T M  (T M  being the melting point of the metal or alloy as expressed in terms of absolute temperature) and then allowing the hydrogen to be released within a temperature range of 0° C. to 0.8 T M , said alloy consisting of alloy crystal grains refined by said heat treatment.  
   
   
       5 . An alloy as set forth in  claim 4  characterized in that the alloy system to which the hydrogen absorption/desorption heat treatment is applicable is mainly an alloy comprising, as an element(s) weak in affinity for hydrogen, an element or a range of elements selected from elements of the groups 6-10 of the periodic table of the elements (except for Pd), typically Cr, Mn, Fe, Co and Ni, and elements of the groups 11-15 of the periodic table of the elements, typically Cu, Ag, Au, Zn and Al.  
   
   
       6 . An alloy as set forth in  claim 4  characterized in that the alloy system to which the hydrogen absorption/desorption heat treatment is applicable contains at least one metal strong in affinity for hydrogen as selected from the group consisting of alkali metals such as Li and Na, alkaline earth metals such as Mg and Ca, rare earth metals such as La and Ce, transition metals of the groups 3-5 of the periodic table of the elements, typically Ti and V, and Pd.  
   
   
       7 . An alloy as set forth in  claim 4  characterized in that the refined crystal grain diameter is 10 nm to 10 μm.  
   
   
       8 . A method of refining crystal grains of an alloy as set forth in  claim 2  which is characterized in that the alloy system to which the hydrogen absorption/desorption heat treatment is applicable contains at least one metal strong in affinity for hydrogen as selected from the group consisting of alkali metals such as Li and Na, alkaline earth metals such as Mg and Ca, rare earth metals such as La and Ce, transition metals of the groups 3-5 of the periodic table of the elements, typically Ti and V, and Pd.  
   
   
       9 . An alloy as set forth in  claim 5  characterized in that the refined crystal grain diameter is 10 nm to 10 μm.  
   
   
       10 . An alloy as set forth in  claim 6  characterized in that the refined crystal grain diameter is 10 nm to 10 μm.