US2026049385A1PendingUtilityA1

Low thermal expansion alloy

Assignee: DAIDO STEEL CO LTDPriority: Aug 14, 2024Filed: Jul 14, 2025Published: Feb 19, 2026
Est. expiryAug 14, 2044(~18.1 yrs left)· nominal 20-yr term from priority
C22C 38/52C22C 38/50C22C 38/48C22C 38/46C22C 38/44C22C 38/42C22C 38/06C22C 38/04C22C 38/02C22C 38/005C22C 38/002C22C 38/001C21D 8/06C21D 8/10C21D 1/26C21D 8/0273C21D 2211/004C21D 9/46C21D 9/08C21D 8/021C21D 8/0226C21D 2261/00C21D 9/0068C22C 38/14C22C 38/58C22C 38/54C22C 38/08C21D 6/001C22C 38/16C22C 38/12C22C 38/105
59
PatentIndex Score
0
Cited by
0
References
0
Claims

Abstract

The present invention relates to a low thermal expansion alloy, consisting of: 0.10 to 0.40 mass % of C; up to 1.00 mass % of Si; 0.10 to 2.00 mass % of Mn; up to 0.050 mass % of P; up to 0.015 mass % of S; 0.10 to 4.00 mass % of Cu; 35.0 to 45.0 mass % of Ni; 0.10 to 1.00 mass % of V; up to 4.00 mass % of Mo; each up to 0.50 mass % of Cr, Co, Al, Ti, Nb, W, Zr, Hf, and Ta; and each up to 0.050 mass % of B, Mg, Ca, and REM, with the balance being Fe and unavoidable impurities. The low thermal expansion alloy satisfies A≥38.0 and 40.6<B≤44.5. Here, A and B are defined in the description.

Claims

exact text as granted — not AI-modified
What is claimed is: 
     
         1 . A low thermal expansion alloy consisting of:
 0.10 mass %≤C≤0.40 mass %;   Si≤1.00 mass %;   0.10 mass %≤Mn≤2.00 mass %;   P≤0.050 mass %;   S≤0.015 mass %;   0.10 mass %≤Cu≤4.00 mass %;   35.0 mass %≤Ni≤45.0 mass %;   0.10 mass %≤V≤1.00 mass %;   0 mass %≤Cr≤0.50 mass %;   0 mass %≤Mo≤4.00 mass %;   0 mass %≤Co≤0.50 mass %;   0 mass %≤Al≤0.50 mass %;   0 mass %≤Ti≤0.50 mass %;   0 mass %≤Nb≤0.50 mass %;   0 mass %≤W≤0.50 mass %;   0 mass %≤Zr≤0.50 mass %;   0 mass %≤Hf≤0.50 mass %;   0 mass %≤Ta≤0.50 mass %;   0 mass %≤B≤0.050 mass %;   0 mass %≤Mg≤0.050 mass %;   0 mass %≤Ca≤0.050 mass %; and   0 mass %≤REM≤0.050 mass %,   with the balance being Fe and unavoidable impurities,   wherein the low thermal expansion alloy satisfies the following formulas (1) and (2):   
       
         
           
             
               
                 
                   
                     
                       A 
                       ≥ 
                       38. 
                     
                     , 
                     and 
                   
                 
                 
                   
                     ( 
                     1 
                     ) 
                   
                 
               
             
           
         
         
           
             
               
                 
                   
                     
                       40.6 
                       < 
                       B 
                       ≤ 
                       
                         4 
                         4.5 
                       
                     
                     , 
                   
                 
                 
                   
                     ( 
                     2 
                     ) 
                   
                 
               
             
           
         
         
           
             wherein 
           
         
         
           
             
               
                 A 
                 = 
                 
                   
                     [ 
                     Ni 
                     ] 
                   
                   + 
                   
                     [ 
                     Co 
                     ] 
                   
                   + 
                   
                     0.7 
                     * 
                     
                       [ 
                       Cu 
                       ] 
                     
                   
                   - 
                   
                     [ 
                     Si 
                     ] 
                   
                   - 
                   
                     [ 
                     Mn 
                     ] 
                   
                   - 
                   
                     [ 
                     Cr 
                     ] 
                   
                   - 
                   
                     0.5 
                     * 
                     
                       [ 
                       Mo 
                       ] 
                     
                   
                   - 
                   
                     0.5 
                     * 
                     
                       [ 
                       V 
                       ] 
                     
                   
                 
               
               , 
             
           
         
         
           
             and 
           
         
         
           
             
               B 
               = 
               
                 
                   [ 
                   Ni 
                   ] 
                 
                 + 
                 
                   0.8 
                   * 
                   
                     [ 
                     Co 
                     ] 
                   
                 
                 + 
                 
                   [ 
                   Cu 
                   ] 
                 
                 + 
                 
                   6 
                   * 
                   
                     [ 
                     C 
                     ] 
                   
                 
                 + 
                 
                   1.1 
                   * 
                   
                     [ 
                     Si 
                     ] 
                   
                 
                 + 
                 
                   [ 
                   Mn 
                   ] 
                 
                 + 
                 
                   1.2 
                   * 
                   
                     [ 
                     Cr 
                     ] 
                   
                 
                 + 
                 
                   0.2 
                   * 
                   
                     [ 
                     Mo 
                     ] 
                   
                 
                 - 
                 
                   0.5 
                   * 
                   
                     
                       [ 
                       V 
                       ] 
                     
                     . 
                   
                 
               
             
           
         
       
     
     
         2 . The low thermal expansion alloy according to  claim 1 , having a tensile strength of 500 MPa or more,
 wherein the “tensile strength” refers to a value obtained by performing a tensile test at room temperature (25° C.) in an atmosphere using a round bar-shaped No. 3 test piece having a parallel portion with a diameter of 6 mm in accordance with ASTM A370-17.   
     
     
         3 . The low thermal expansion alloy according to  claim 1 , having a thermal expansion coefficient of 3.5×10 −6 /° C. or more and 6.0×10 −6 /° C. or less,
 wherein the “thermal expansion coefficient” refers to an average linear thermal expansion coefficient from 30° C. to 100° C., measured in accordance with ASTM E228-17. 
 
     
     
         4 . The low thermal expansion alloy according to  claim 1 , having a magnetic transformation point of 280° C. or higher. 
     
     
         5 . The low thermal expansion alloy according to  claim 1 , wherein the unavoidable impurities include at least one selected from the group consisting of:
 Sn≤0.010 mass %;   Zn≤0.010 mass %;   As≤0.010 mass %;   Se≤0.010 mass %;   Sb≤0.010 mass %;   Ag≤0.010 mass %;   Bi≤0.0010 mass %;   O≤0.050 mass %, and   N≤0.050 mass %.

Join the waitlist — get patent alerts

Track US2026049385A1 — get alerts on status changes and closely related new filings.

We store only your email — no account needed. See our privacy policy.