Non-ferromagnetic amorphous steel alloys containing large-atom metals

Abstract

The present invention relates to novel non-ferromagnetic amorphous steel alloys represented by the general formula: Fe—Mn-(Q)-B-M, wherein Q represents one or more elements selected from the group consisting of Sc, Y, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, and M represents one or more elements selected from the group consisting of Cr, Co, Mo, C and Si. Typically the atomic percentage of the Q constituent is 10 or less. An aspect is to utilize these amorphous steels as coatings, rather than strictly bulk structural applications. In this fashion any structural metal alloy can be coated by various technologies by these alloys for protection from the environment. The resultant structures can utilize surface and bulk properties of the amorphous alloy.

We claim: 
     
       1. An amorphous alloy represented by the formula:
   Fe 48 Cr 15 Mo 14 Er 2 C 15 B 6    
 and wherein for a test duration said alloy is exposed to an environment having a designated pH level, said alloy is determined to have a differential voltage, V, wherein differential voltage, V, equals E pit −E oc , wherein E pit  is pitting potential and E oc  is open circuit potential, wherein: 
 said alloy has a voltage differential, V, that is determined to have at least one of the following magnitudes: 
 if said PH level is equal to about 1.0, then V is equal to about 0.710 if said PH level is equal to about 6.5, then V is equal to about 0.883 and if said PH level is equal to about 11.0, then V is equal to about 1.129. 
 
     
     
       2. The alloy of  claim 1 , wherein said alloy is processable into bulk amorphous samples of less than about 0.1 mm in thickness in its minimum dimension. 
     
     
       3. The alloy of  claim 1 , wherein said alloy is processable into bulk amorphous samples of at least about 0.1 mm in thickness in its minimum dimension. 
     
     
       4. The alloy of  claim 1 , wherein said alloy is processable into bulk amorphous samples of at least about 0.5 mm in thickness in its minimum dimension. 
     
     
       5. The alloy of  claim 1 , wherein said alloy is processable into bulk amorphous samples of at least about 1 mm in thickness in its minimum dimension. 
     
     
       6. The alloy of  claim 1 , wherein said alloy is processable into bulk amorphous samples of at least about 5 mm in thickness in its minimum dimension. 
     
     
       7. The alloy of  claim 1 , wherein said alloy is processable into bulk amorphous samples of at least about 10 mm in thickness in its minimum dimension. 
     
     
       8. The alloy of  claim 1 , wherein said alloy is processable into bulk amorphous samples of at least about 12 mm in thickness in its minimum dimension. 
     
     
       9. The alloy of  claim 1 , wherein said alloy is processable into an article. 
     
     
       10. The alloy of  claim 9 , wherein said processed article is provided by at least one of the following processing methods: melt spinning, atomization, spray forming, scanning-beam forming, plastic forming, casting, and compaction. 
     
     
       11. The alloy of  claim 1 , wherein said alloy is processable into a coating. 
     
     
       12. The alloy of  claim 11 , wherein said processed coating is provided by at least one of the following processing methods: melt spinning, atomization, spray forming, scanning-beam forming, plastic forming, casting, and compaction. 
     
     
       13. The alloy of  claim 11 , wherein said coating comprises corrosion resistant type coating and/or wear-resistant type coating. 
     
     
       14. The alloy of  claim 11 , wherein said coating is disposed on a structure selected from the group consisting of ship frames, submarine frames, vehicle frames, airplane walls and frames, ship walls, submarine walls, vehicle walls, armor penetrators, projectiles, protection armors, rods, train rails, cable armor, power shaft, and actuators, hand tools and medical implants and devices, cell phone and PDA casings, housings, and interior components, electronics and computer casings, housings and interior components. 
     
     
       15. The alloy of  claim 1 , wherein said alloy is processable into a structure selected from the group consisting of ship frames, submarine frames, vehicle frames, ship walls, submarine walls, vehicle walls, armor penetrators, projectiles, protection armors, rods, train rails, cable armor, power shaft, and actuators, hand tools and medical implants and devices, cell phone and PDA casings, housings, and interior components, electronics and computer casings, housings and interior components. 
     
     
       16. The alloy of  claim 1 , wherein said test duration is less than about 1 hour. 
     
     
       17. The alloy of  claim 1 , wherein said test duration is about 1 hour. 
     
     
       18. The alloy of  claim 1 , wherein said test duration is greater than about 1 hour. 
     
     
       19. An amorphous alloy represented by the formula:
   Fe 50 Cr 15 Mo 14 C 15 B 6    
 and wherein for a test duration said alloy is exposed to an environment having a designated pH level, said alloy is determined to have a differential voltage, V, wherein differential voltage, V, equals E pit −E oc , wherein E pit  is pitting potential and E oc  is open circuit potential, wherein: 
 said alloy has a voltage differential, V, that is determined to have at least one of the following magnitudes:
 if said PH level is equal to about 1.0, then V is equal to about 0.087; 
 if said PH level is equal to about 6.5, then V is equal to about 0.244; and 
 if said PH level is equal to about 11.0, then V is equal to about 0.777. 
 
 
     
     
       20. The alloy of  claim 19 , wherein said alloy is processable into bulk amorphous samples of less than about 0.1 mm in thickness in its minimum dimension. 
     
     
       21. The alloy of  claim 19 , wherein said alloy is processable into bulk amorphous samples of at least about 0.1 mm in thickness in its minimum dimension. 
     
     
       22. The alloy of  claim 19 , wherein said alloy is processable into bulk amorphous samples of at least about 0.5 mm in thickness in its minimum dimension. 
     
     
       23. The alloy of  claim 19 , wherein said alloy is processable into bulk amorphous samples of at least about 1 mm in thickness in its minimum dimension. 
     
     
       24. The alloy of  claim 19 , wherein said alloy is processable into hulk bulk amorphous samples of at least about 5 mm in thickness in its minimum dimension. 
     
     
       25. The alloy of  claim 19 , wherein said alloy is processable into bulk amorphous samples of at least about 10 mm in thickness in its minimum dimension. 
     
     
       26. The alloy of  claim 19 , wherein said alloy is processable into bulk amorphous samples of at least about 12 mm in thickness in its minimum dimension. 
     
     
       27. The alloy of  claim 19 , wherein said alloy is processable into an article. 
     
     
       28. The alloy of  claim 27 , wherein said processed article is provided by at least one of the following processing methods: melt spinning, atomization, spray forming, scanning-beam forming, plastic forming, casting, and compaction. 
     
     
       29. The alloy of  claim 19 , wherein said alloy is processable into a coating. 
     
     
       30. The alloy of  claim 29 , wherein said processed coating is provided by at least one of the following processing methods: melt spinning, atomization, spray forming, scanning-beam forming, plastic forming, casting, and compaction. 
     
     
       31. The alloy of  claim 29 , wherein said coating comprises corrosion resistant type coating and/or wear-resistant type coating. 
     
     
       32. The alloy of  claim 29 , wherein said coating is disposed on a structure selected from the group consisting of ship frames, submarine frames, vehicle frames, airplane walls and frames, ship walls, submarine walls, vehicle walls, armor penetrators, projectiles, protection armors, rods, train rails, cable armor, power shaft, and actuators, hand tools and medical implants and devices, cell phone and PDA casings, housings, and interior components, electronics and computer casings, housings and interior components. 
     
     
       33. The alloy of  claim 19 , wherein said alloy is processable into a structure selected from the group consisting of ship frames, submarine frames, vehicle frames, ship walls, submarine walls, vehicle walls, armor penetrators, projectiles, protection armors, rods, train rails, cable armor, power shaft, and actuators, hand tools and medical implants and devices, cell phone and PDA casings, housings, and interior components, electronics and computer casings, housings and interior components. 
     
     
       34. The alloy of  claim 19 , wherein said test duration is less than about 1 hour. 
     
     
       35. The alloy of  claim 19 , wherein said test duration is about 1 hour. 
     
     
       36. The alloy of  claim 19 , wherein said test duration is greater than about 1 hour. 
     
     
       37. An iron-based bulk-solidifying amorphous alloy comprising at least four elements including Fe, and having the formula Fe—Mn—Cr—Mo—(C, B)-Q, where Q is a large-atom element selected from the group consisting of Sc, Y, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, an amount of Mn is from 10 to 12 atomic %, an amount of chromium is from 0 to 16 atomic %, an amount of Mo is from 8 to 16 atomic %, an amount of (C, B) is greater than 18 atomic %, with an amount of C being at least 13 atomic % and an amount of B being at least 5 atomic %, and an amount of Q is greater than zero and less than or equal to 3 atomic %, and the bulk-solidifying amorphous alloy is non-ferromagnetic at ambient temperature. 
     
     
       38. The bulk-solidifying amorphous alloy of claim 37, wherein an amount of Fe is at least 45 atomic %. 
     
     
       39. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a magnetic transition temperature below ambient temperature. 
     
     
       40. The bulk-solidifying amorphous alloy of claim 37, wherein the large-atom element is Y, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu or combinations thereof. 
     
     
       41. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a microhardness in the range of about 1000-1300 DPN. 
     
     
       42. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a fracture toughness in a range of about 3 to 4 GPa. 
     
     
       43. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a Young's modulus in a range of about 180-210 GPa. 
     
     
       44. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a bulk modulus in a range of about 140-190 GPa. 
     
     
       45. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a glass transition temperature of about 530° C. or greater. 
     
     
       46. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a reduced glass temperature of about 0.58 or greater. 
     
     
       47. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a supercooled liquid region of about 30° C. or greater. 
     
     
       48. The bulk-solidifying amorphous alloy of claim 37, wherein the bulk-solidifying amorphous alloy has a liquidus onset temperature in a range from about 1065° C. to 1105° C. 
     
     
       49. The bulk-solidifying amorphous alloy of claim 37, wherein the alloy further comprises 2 atomic % or less of one or elements selected from Ti, Zr, Hf, Nb, V, Ta, W, Al, Ga, In, Sn, Si, Ge, and Sb.