High-silicon stainless

Abstract

A high-Si stainless steel excellent in various characteristics, inclusive of strength, corrosion resistance, workability and castability, consists of, on the mass % basis, Si: 2 to 5%, Cr: 8 to 25%, Ni: 4 to 16%, Mn: not more than 5%, Cu: not more than 4%, Co: not more than 8%, Mo: not more than 4%, Nb: not more than 3%, Ta: not more than 3%, Ti: not more than 3%, W: not more than 4%, V: not more than 4%, B: not more than 0.01%, Mg: not more than 0.01%, Ca: not more than 0.01%, rare earth elements: not more than 0.01%, the balance being Fe. Impurities in this steel are as follows: C: not more than 0.04%, P: not more than 0.03%, S: not more than 0.02%, Al: not more than 0.03%, N (nitrogen): not more than 0.05%, O (oxygen): not more than 0.005%, and H (hydrogen): not more than 0.0003%.

1 . A high-silicon stainless steel consisting of, on the mass % basis, Si: 2 to 5%, Cr: 8 to 25%, Ni: 4 to 16%, Mn: not more than 5%, Cu: not more than 4%, Co: not more than 8%, Mo: not more than 4%, Nb: not more than 3%, Ta: not more than 3%, Ti: not more than 3%, W: not more than 4%, V: not more than 4%, B: not more than 0.01%, Mg: not more than 0.01%, Ca: not more than 0.01%, and rare earth elements: not more than 0.01%, the balance being Fe, wherein the contents of impurities are as follows: C: not more than 0.04%, P: not more than 0.03%, S: not more than 0.02%, Al: not more than 0.03%, N (nitrogen): not more than 0.05%, O (oxygen): not more than 0.005%, and H (hydrogen): not more than 0.0003%.  
     
     
         2 . A high-silicon stainless steel consisting of, on the mass % basis, 2.5 to 4.5% of Si, 9 to 20% of Cr, 5 to 15% of Ni, 0.05 to 5% of Mn, 0 to 6% of Co, 0.2 to 4% of Mo, 0 to 1.5% of W, 0 to 1.5% of V, and 0 to 0.006% of B, the balance being Fe and impurities, wherein the contents of impurities are as follows: C: not more than 0.04%, P: not more than 0.015%, S: not more than 0.01%, Al: not more than 0.01%, N (nitrogen): not more than 0.03%, O (oxygen): not more than 0.002%, and H (hydrogen): not more than 0.0002%.  
     
     
         3 . A high-silicon stainless steel consisting of, on the mass % basis, 2.5 to 4.5% of Si, 9 to 20% of Cr, 5 to 15% of Ni, 0.05 to 5% of Mn, 0 to 6% of Co, 0.2 to 4% of Mo, 0 to 1.5% of W, 0 to 1.5% of V, 0 to 0.006% of B, and at least one element selected from the group consisting of 0.5 to 4% of Cu, 0.1 to 1.5% of Nb, 0.1 to 1.5% of Ta and 0.1 to 1.5% of Ti, the balance being Fe and impurities, wherein the contents of impurities are as follows: C: not more than 0.04%, P: not more than 0.015%, S: not more than 0.01%, Al: not more than 0.01%, N (nitrogen): not more than 0.03%, O (oxygen): not more than 0.002%, and H (hydrogen): not more than 0.0002%.  
     
     
         4 . A high-silicon stainless steel according to  claim 1 ,  2  or  3 , wherein the Cr equivalent (X) defined by the formula (1) given below and the Ni equivalent (Y) defined by the formula (2) given below satisfy the relations (3), (4) and (5) given below: 
         X  ( Cr  equivalent, %)= Cr  (%)+0.3 ×Mo  (%)+1.5× Si  (%)+0.5× Nb  (%)  (1) Y  ( Ni  equivalent, %)= Ni  (%)+30 ×C  (%)+0.5× Mn  (%)+0.1× Co  (%)  (2) Y≧ 19.20−0.81  X   (3) Y≦ −8.48+1.03  X   (4) Y≧ −5.00+0.50  X   (5) 
     
     
         5 . A high-silicon stainless steel as claimed in  claim 1 ,  2  or  3 , wherein the Cr equivalent (X) defined by the formula (1) given below and the Ni equivalent (Y) defined by the formula (2) given below satisfy the relations (3), (4), (5) and (6) given below: 
         X  ( Cr  equivalent, %)= Cr  (%)+0.3 ×Mo  (%)+1.5× Si  (%)+0.5 ×Nb  (%)  (1) Y  ( Ni  equivalent, %)= Ni  (%)+30× C  (%)+0.5× Mn  (%)+0.1 ×Co  (%)  (2) Y≧ 19.20−0.81  X   (3) Y≦ −8.48+1.03  X   (4) Y≧− 5.00+0.50  X   (5) Y≦ 25.40−0.80  X   (6) 
     
     
         6 . A steel wire having a diameter of not greater than 40 μm produced from the steel according to any of  claims 1  to  5 .  
     
     
         7 . A part for bearing or supporting equipment or quake-absorbing equipment produced from the steel according to any of  claims 1  to  5 .  
     
     
         8 . A part for semiconductor production apparatus produced from the steel according to any of  claims 1  to  5 .