阅读说明：本技术 一种s31254超级奥氏体不锈钢的生产工艺 (Production process of S31254 super austenitic stainless steel ) 是由 史咏鑫 钟庆元 才丽娟 冯文静 葛书可 于 2019-09-20 设计创作，主要内容包括：本发明公开了一种S31254超级奥氏体不锈钢的生产工艺,包括以下步骤：A、向坩埚中投入原料,坩埚内抽真空,升温至1550～1570℃进行熔化；B、向熔融原料中注入氮气,进行搅拌熔炼；C、提高坩埚内氮气含量,使气压保持在0.07～0.08MPa,原料温度降低至1430～1490℃,进行浇铸；D、对浇铸后的原料进行冷却成型,温度降低至850～900℃,进行锻造,锻造比为4.3～4.8；E、对原料钢锭进行加热,升温至1100～1150℃,保温30min后以低于70℃/min的速度降低至室温。本发明能够改进现有技术的不足,提高了氮气注入方式的超级奥氏体不锈钢的含氮量。(the invention discloses a production process of S31254 super austenitic stainless steel, which comprises the following steps: A. putting raw materials into a crucible, vacuumizing the crucible, and heating to 1550-1570 ℃ for melting; B. injecting nitrogen into the molten raw materials, and stirring and smelting; C. increasing the nitrogen content in the crucible to keep the air pressure at 0.07-0.08 MPa, and reducing the temperature of the raw materials to 1430-1490 ℃ for casting; D. cooling and forming the cast raw materials, reducing the temperature to 850-900 ℃, and forging, wherein the forging ratio is 4.3-4.8; E. and heating the raw material steel ingot to 1100-1150 ℃, preserving the temperature for 30min, and then reducing the temperature to room temperature at a speed of less than 70 ℃/min. The invention can improve the defects of the prior art and improve the nitrogen content of the super austenitic stainless steel in a nitrogen injection mode.)

1. A production process of S31254 super austenitic stainless steel is characterized by comprising the following steps:

A. Putting raw materials into a crucible, vacuumizing the crucible, heating to 1550-1570 ℃ for melting, wherein the raw materials comprise,

less than or equal to 0.05 wt% of carbon, less than or equal to 1.00 wt% of manganese, 17.0-18.1 wt% of nickel, less than or equal to 0.2 wt% of silicon, less than or equal to 0.03 wt% of phosphorus, less than or equal to 0.01 wt% of sulfur, 20.0-21.0 wt% of chromium, 0.2-0.7 wt% of copper, 6.0-6.5 wt% of molybdenum, 0.05-0.1 wt% of zirconium, 0.02-0.05 wt% of tungsten and the balance of iron;

B. Injecting nitrogen into the molten raw materials, stirring and smelting, wherein the injection amount of the nitrogen is 0.3-0.5 m³Keeping the air pressure in the crucible within 100Pa for 20-30 min;

C. Increasing the nitrogen content in the crucible to keep the air pressure at 0.07-0.08 MPa, and reducing the temperature of the raw materials to 1430-1490 ℃ for casting;

D. Cooling and forming the cast raw materials, reducing the temperature to 850-900 ℃, and forging, wherein the forging ratio is 4.3-4.8;

E. and heating the raw material steel ingot to 1100-1150 ℃, preserving the temperature for 30min, and then reducing the temperature to room temperature at a speed of less than 70 ℃/min.

2. The process for producing S31254 super austenitic stainless steel according to claim 1, characterized in that: in the step A, the raw material also comprises 0.01-0.02 wt% of cerium.

3. The process for producing S31254 super austenitic stainless steel according to claim 2, characterized in that: and in the step B, nitrogen is injected by simultaneously injecting nitrogen into the top and the bottom, wherein the injection amount of the nitrogen at the top is 30-50% of that at the bottom.

4. a process of producing S31254 super austenitic stainless steel according to claim 3, characterized in that: in the step D, the forging pressure is 600-650 MPa.

5. The process for producing S31254 super austenitic stainless steel according to claim 4, wherein: and E, cooling at the speed of 65 ℃/min when the cooling is started, stopping cooling when the temperature is reduced to 500 ℃, keeping the temperature for 10min, and then reducing to the room temperature at the speed of 30 ℃/min.

Technical Field

the invention relates to the technical field of metallurgy, in particular to a production process of S31254 super austenitic stainless steel.

Background

The super austenitic stainless steel has the characteristics of corrosion resistance and excellent cold and hot processing performance, and is widely applied to the production and processing of various products. The toughness and yield strength of the super austenitic stainless steel can be further improved by increasing the nitrogen content of the super austenitic stainless steel. However, how to increase the nitrogen content by a low-cost nitrogen injection method on the basis of keeping the original crystal structure is always a technical problem in the field.

Disclosure of Invention

The invention aims to solve the technical problem of providing a production process of S31254 super austenitic stainless steel, which can solve the defects of the prior art and improve the nitrogen content of the super austenitic stainless steel in a nitrogen injection mode.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows.

A production process of S31254 super austenitic stainless steel comprises the following steps:

A. Putting raw materials into a crucible, vacuumizing the crucible, heating to 1550-1570 ℃ for melting, wherein the raw materials comprise,

Less than or equal to 0.05 wt% of carbon, less than or equal to 1.00 wt% of manganese, 17.0-18.1 wt% of nickel, less than or equal to 0.2 wt% of silicon, less than or equal to 0.03 wt% of phosphorus, less than or equal to 0.01 wt% of sulfur, 20.0-21.0 wt% of chromium, 0.2-0.7 wt% of copper, 6.0-6.5 wt% of molybdenum, 0.05-0.1 wt% of zirconium, 0.02-0.05 wt% of tungsten and the balance of iron;

B. injecting nitrogen into the molten raw materials, stirring and smelting, wherein the injection amount of the nitrogen is 0.3-0.5 m³h, the pressure in the crucible is maintained at 100Pa toContinuously keeping for 20-30 min;

C. Increasing the nitrogen content in the crucible to keep the air pressure at 0.07-0.08 MPa, and reducing the temperature of the raw materials to 1430-1490 ℃ for casting;

D. Cooling and forming the cast raw materials, reducing the temperature to 850-900 ℃, and forging, wherein the forging ratio is 4.3-4.8;

E. and heating the raw material steel ingot to 1100-1150 ℃, preserving the temperature for 30min, and then reducing the temperature to room temperature at a speed of less than 70 ℃/min.

Preferably, in the step A, the raw material further comprises 0.01-0.02 wt% of cerium.

preferably, in the step B, nitrogen is injected in a mode of simultaneously injecting nitrogen at the top and the bottom, and the injection amount of the nitrogen at the top is 30-50% of that at the bottom.

preferably, in the step D, the forging pressure is 600 to 650 MPa.

Preferably, in step E, the temperature is reduced at a rate of 65 ℃/min when the temperature is reduced to 500 ℃, the temperature is stopped, the temperature is kept for 10min, and then the temperature is reduced to room temperature at a rate of 30 ℃/min.

adopt the beneficial effect that above-mentioned technical scheme brought to lie in: according to the invention, the forging processing with high forging ratio is realized by improving the raw material ratio and increasing the nitrogen injection amount, and the toughness and yield strength of the super austenitic stainless steel are effectively improved.

Drawings

FIG. 1 is a microcrystalline structure of a super austenitic stainless steel according to example 1.

FIG. 2 is a microcrystalline structure of a super austenitic stainless steel according to example 2.

FIG. 3 is a microcrystalline structure of a super austenitic stainless steel according to example 3.

FIG. 4 is a microcrystalline structure of a super austenitic stainless steel of example 4.

FIG. 5 is a microcrystalline structure of a superaustenitic stainless steel of the comparative example.

Detailed Description