US 11,951,530 B2
High-strength stainless steel rotor and method for preparing the same
Zhenbao Liu, Beijing (CN); Jianxiong Liang, Beijing (CN); Xiaohui Wang, Beijing (CN); Yongqing Sun, Beijing (CN); Changjun Wang, Beijing (CN); and Zhiyong Yang, Beijing (CN)
Assigned to CENTRAL IRON AND STEEL RESEARCH INSTITUTE, Beijing (CN)
Appl. No. 17/638,179
Filed by CENTRAL IRON AND STEEL RESEARCH INSTITUTE, Beijing (CN)
PCT Filed Apr. 29, 2021, PCT No. PCT/CN2021/090831
§ 371(c)(1), (2) Date Feb. 24, 2022,
PCT Pub. No. WO2021/219056, PCT Pub. Date Nov. 4, 2021.
Claims priority of application No. 202010357799.5 (CN), filed on Apr. 29, 2020.
Prior Publication US 2022/0331856 A1, Oct. 20, 2022
Int. Cl. B21J 5/00 (2006.01); B21J 5/02 (2006.01); C21D 9/00 (2006.01); C22C 38/04 (2006.01); C22C 38/42 (2006.01); C22C 38/44 (2006.01); C22C 38/46 (2006.01); C22C 38/48 (2006.01); G01C 19/06 (2006.01)
CPC B21J 5/002 (2013.01) [B21J 5/02 (2013.01); C21D 9/0081 (2013.01); C22C 38/04 (2013.01); C22C 38/42 (2013.01); C22C 38/44 (2013.01); C22C 38/46 (2013.01); C22C 38/48 (2013.01); G01C 19/06 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A method for preparing a high-strength stainless steel rotor, the high-strength stainless steel rotor comprising the following element components by mass percentage: C: 0.03-0.050%, Cr: 14.90-15.80%, Ni: 5.00-5.70%, Cu: 2.20-2.80%, (Nb+Ta): 0.35-0.44%, Mo: 0.45-0.54%, V: 0.06-0.10%, Si: 0.20-0.60%, Mn: 0.40-0.80%, P≤0.010%, S≤0.010%, O≤0.003%, and the balance of iron and inevitable impurities, and the method comprising the following steps:
step 1: preparing a rotor stainless steel billet;
step 2: subjecting the rotor stainless steel billet to a first heating and a free forging, and then a first annealing and a surface treatment to obtain a forged billet;
step 3: subjecting the forged billet to a second heating, a die forging, and then a second annealing and a solution treatment to obtain a forging; and
step 4: subjecting the forging to a rough machining, an aging treatment and a finish machining to obtain the high-strength stainless steel rotor,
wherein the die forging is conducted by pressing deformation on the forging billet with a lower die for 5 times, and the 5 times of pressing deformation are conducted as follows:
a first pressing deformation is conducted by pressing the forged billet using an upper die with a pressure of 2,000-3,000 tons;
a second pressing deformation and a third pressing deformation are conducted by pressing the forged billet using the upper die with a pressure of not less than 5,000 tons;
a fourth pressing deformation is conducted by pressing the forged billet with a pressure of 4,500 tons; and
a fifth pressing deformation is conducted by pressing the forged billet with a pressure of 4,000 tons for 30-40 s.