High entropy alloy for external components

Abstract

A high entropy alloy with a composition containing between 4 and 9 major alloying elements chosen from the list including Cr, Fe, V, Al, Si, Mn, Mo, Ti and Ni with: 3 major alloying elements which are Cr, Fe and V, each having an atomic concentration include between 20 and 40%, 1 or 2 major alloying elements chosen from Al and Si each having an atomic concentration higher than or equal to 5% with a total concentration of these 2 major alloying elements of less than or equal to 25%, 0, 1, 2, 3 or 4 major alloying elements chosen from Mn, Mo, Ti and Ni, each having an atomic concentration higher than or equal to 5% with a total atomic concentration of these 4 major alloying elements of less than or equal to 35%, the total atomic concentration of the 4 to 9 major alloying elements being higher than or equal to 80%, the remainder being made up of any impurities and/or one or more minor alloying elements, each in an atomic concentration of less than 5%.

1 . A high entropy alloy with a composition containing between 4 and 9 major alloying elements chosen from the list comprising Cr, Fe, V, Al, Si, Mn, Mo, Ti and Ni with:
 3 major alloying elements which are Cr, Fe and V, each having an atomic concentration comprised between 20 and 40%,   1 or 2 major alloying elements chosen from Al and Si each having an atomic concentration higher than or equal to 5% with a total concentration of these 2 major alloying elements of less than or equal to 25%,   0, 1, 2, 3 or 4 major alloying elements chosen from Mn, Mo, Ti and Ni, each having an atomic concentration higher than or equal to 5% with a total atomic concentration of these 4 major alloying elements of less than or equal to 35%,   
       the total atomic concentration of all of the 4 to 9 major alloying elements being higher than or equal to 80% and the remainder being made up of impurities and/or one or more minor alloying elements each having an atomic concentration of less than 5%. 
     
     
         2 . The alloy according to  claim 1 , wherein the minor elements are chosen from the list including Si, Mn, Mo, Al, Nb, H, B, C, N, O, Mg, Sc, Ti, Cu, Ni, Zn, Ga, Ge, Sr, Y, Zr, Rh, Pd, Ag, Sn, Sb, Hf, Ta, W, Pt and Au. 
     
     
         3 . The alloy according to  claim 1 , wherein the alloy contains between 0.00.5 and 0.1% atomic concentration of B as minor alloying element. 
     
     
         4 . The alloy according to  claim 1 , wherein the alloy contains between 7 and 15% atomic concentration of Ni as major alloying element. 
     
     
         5 . The alloy according to  claim 1 , wherein the alloy meets one of the following formulae expressed in atomic fractions: Al10Fe25Cr40V25, Al10Fe40Cr25V25, Al10Fe25Cr25V40, Al10Fe30Cr30V30, Al5Cr30Fe30Mo5V30, Al6Cr30Fe30Mo5V29, Al5Cr30Fe30Si5V30, Al5Cr30Fe30Mn5V30, Al13Cr25Fe25Ni12V25 Cr31Fe31V31Si7 or Fe25Cr25V25Al10Ni10Ti5. 
     
     
         6 . The alloy according to  claim 1 , wherein the alloy includes a single-phase, body-centred cubic solid solution. 
     
     
         7 . The alloy according to  claim 1 , wherein the alloy has a two-phase structure including a body-centred cubic matrix and nanoprecipitates. 
     
     
         8 . The alloy according to  claim 1 , wherein the alloy exhibits non-ferromagnetic behaviour and does not exhibit signs of corrosion after being subjected to the salt spray test according to ISO standard 9227. 
     
     
         9 . The alloy according to  claim 1 , wherein the alloy has a hardness HV10 higher than or equal to 400. 
     
     
         10 . An external component for horology or jewellery, wherein the component is made from an high entropy alloy with a composition containing between 4 and 9 major alloying elements chosen from the list comprising Cr, Fe, V, Al, Si, Mn, Mo, Ti and Ni with:
 3 major alloying elements which are Cr, Fe and V, each having an atomic concentration comprised between 20 and 40%,   1 or 2 major alloying elements chosen from Al and Si each having an atomic concentration higher than or equal to 5% with a total concentration of these 2 major alloying elements of less than or equal to 25%,   0, 1, 2, 3 or 4 major alloying elements chosen from Mn, Mo, Ti and Ni, each having an atomic concentration higher than or equal to 5% with a total atomic concentration of these 4 major alloying elements of less than or equal to 35%.   
     
     
         11 . A component according to  claim 10 , wherein the component is chosen from the list including a case middle, a case back, a bezel, a pusher, a crown, a bracelet link, a clasp, a buckle, a prong, a dial, a hand and a how symbol.