阅读说明：本技术 船舶泵阀用抗微生物黏附耐海水腐蚀双相不锈钢及其制备方法和应用 (Antimicrobial adhesion seawater corrosion resistant duplex stainless steel for ship pump valve and preparation method and application thereof ) 是由 肖学山 黄周远 李钧 于 2020-05-26 设计创作，主要内容包括：本发明公开了一种船舶泵阀用抗微生物黏附耐海水腐蚀双相不锈钢及其制备方法和应用。本发明泵阀材料通过热处理工艺控制,分别在高温两相区进行固溶处理后,再在低温进行一次时效和二次时效处理,保证铁素体-奥氏体双相组织提高硬度到30-40HRC,从而改善材料的切削加工性能；同时在保温时效的过程中,以确保材料中添加的合金元素Cu以ε-Cu相从基体中析出,尺寸约在80～150nm,进一步改善了加工性能,同时获得抗菌防微生物黏附的能力。本发明在保证耐海水腐蚀和防海洋微生物黏附的前提下解决了目前市场上使用铜合金船舶泵阀材料成本高昂、以及使用奥氏体不锈钢难于切削和不耐海水腐蚀的难题,可以广泛使用在船舶泵阀上。(The invention discloses an antimicrobial adhesion seawater corrosion resistant duplex stainless steel for a ship pump valve, and a preparation method and application thereof. The pump valve material is controlled by a heat treatment process, and after solid solution treatment is respectively carried out in a high-temperature two-phase region, primary aging treatment and secondary aging treatment are carried out at a low temperature, so that the hardness of a ferrite-austenite two-phase structure is improved to 30-40HRC, and the cutting processability of the material is improved; meanwhile, in the process of heat preservation and aging, the alloy element Cu added in the material is ensured to be separated out from the matrix in a-Cu phase, the size is about 80-150 nm, the processing performance is further improved, and the capability of resisting bacteria and preventing microorganism adhesion is obtained. The invention solves the problems of high cost of the copper alloy ship pump valve material, difficult cutting and seawater corrosion resistance by using austenitic stainless steel in the current market on the premise of ensuring seawater corrosion resistance and marine microorganism adhesion prevention, and can be widely used on the ship pump valve.)

1. An antimicrobial adhesion seawater corrosion resistant duplex stainless steel for ship pump valves is characterized in that: the alloy comprises the following components in percentage by mass: less than or equal to 0.03 percent of C, less than or equal to 0.03 percent of S, less than or equal to 0.04 percent of P, less than or equal to 0.20 percent of N, 19.00 to 24.00 percent of Cr, 2.0 to 4.00 percent of Cu, Ni: 3.00-4.50%, Mo: 0.3-1.0%, and the balance of iron and inevitable other impurities.

2. The marine pump valve anti-microbial adhesion seawater corrosion resistant duplex stainless steel according to claim 1, wherein: the weight percentages of the components are as follows: c: 0.010-0.02%, S is less than or equal to 0.008%, P is less than or equal to 0.04%, N: 0.002 to 0.15%, 19.50 to 22.60% of Cr, 2.50 to 3.5% of Cu, Ni: 3.00-3.50%, Mo: 0.4-0.8%, and the balance of iron and inevitable impurities.

3. The marine pump valve anti-microbial adhesion seawater corrosion resistant duplex stainless steel according to claim 2, wherein: the weight percentages of the components are as follows: c: 0.010-0.012%, S: 0.005-0.006%, P is less than or equal to 0.04%, N: 0.002-0.131%, 19.54-19.57% of Cr, 2.63-2.78% of Cu, Ni: 3.18-3.24%, Mo: 0.41-0.45%, and the balance of iron and inevitable impurities.

4. The marine pump valve anti-microbial adhesion seawater corrosion resistant duplex stainless steel according to claim 1, wherein: wherein the alloy element Cu is dispersed and precipitated from the material matrix in a-Cu phase and is uniformly distributed, the size of the-Cu phase is 80-150 nm, and the hardness value of the material is 30-40 HRC.

5. Use of an anti-microbial adhesion seawater corrosion resistant duplex stainless steel for marine pump valves according to claim 1, wherein: the marine pump valve casting resistant to seawater corrosion and microbial adhesion is manufactured by adopting the marine pump valve antimicrobial adhesion seawater corrosion resistant duplex stainless steel.

6. A method for preparing the marine pump valve marine corrosion resistant marine pump valve marine pump:

a. preparing raw materials:

weighing the following raw materials in percentage by mass:

c is less than or equal to 0.03 percent, S is less than or equal to 0.03 percent, P is less than or equal to 0.04 percent, N: 0.00-0.20%, 19.00-24.00% of Cr, 2.00-4.00% of Cu, and Ni: 3.00-4.50%, Mo: 0.30-1.00% of iron for later use;

b. the casting processing casting process comprises the following steps:

smelting the raw materials taken in the step a by a medium-frequency induction furnace or an electric furnace, and then preparing pump valve castings for marine ships by a series of processes such as AOD smelting, casting, heat treatment, turning forming, welding and the like;

c. the post-treatment process for heat treatment strengthening comprises the following steps:

and c, carrying out solution treatment on the pump valve casting prepared in the step b in a high-temperature two-phase region, then carrying out primary aging treatment and secondary aging treatment at a low temperature, obtaining a material with a ferrite-austenite duplex structure through a heat preservation solution treatment process, and simultaneously precipitating alloy element Cu added in the material from a matrix in a Cu phase in the heat preservation aging treatment process so as to obtain the antimicrobial adhesion seawater corrosion resistant duplex stainless steel for the pump valve of the ship.

7. The method for preparing the marine pump valve marine corrosion resistant duplex stainless steel according to claim 6, wherein: in the step a, the raw materials are weighed according to the following mass percentages: c: 0.010-0.02%, S is less than or equal to 0.008%, P is less than or equal to 0.04%, N: 0.002 to 0.15%, 19.50 to 22.60% of Cr, 2.50 to 3.5% of Cu, Ni: 3.00-3.50%, Mo: 0.4-0.8% and the balance of iron.

8. The method for preparing the marine pump valve marine corrosion resistant marine pump valve antimicrobial adherence duplex stainless steel according to claim 5, wherein: in the step c, when the solution treatment is carried out in the high-temperature two-phase region, the temperature is controlled to be 1000-1200 ℃, and the solution treatment time is 0.5-2 h.

9. The method for preparing the marine pump valve marine corrosion resistant duplex stainless steel according to claim 6, wherein: and c, performing heat preservation and aging treatment, wherein the primary aging heat preservation time is not more than 2 hours, the secondary aging time is 2-8 hours, and the temperature for performing the heat preservation and aging treatment is controlled to be 300-800 ℃, so that the hardness of the aged material is about 30-40 HRC.

Technical Field

The invention relates to a duplex stainless steel, a preparation method and application thereof, in particular to a seawater corrosion resistant duplex stainless steel, a preparation method and application thereof, which are applied to the technical field of new stainless steel materials and preparation processes thereof.

Background

No matter natural gas, tap water, petroleum and the like are transported without leaving pipelines, and especially the performance requirements of pump valves at pipeline joints are higher and higher. Nowadays, alloy materials such as copper alloy, austenitic stainless steel, cast iron and the like are mostly applied to ship pump valve materials, and the materials have great limitations in terms of cost and use environment. On one hand, the part of the current market uses 316L austenitic stainless steel to replace Cu alloy, but the 316L austenitic stainless steel has small hardness and poor processing performance, and is easy to stick a cutter in the cutting process, so that the advantages brought by the cost price of raw materials are greatly offset by the increase of the processing cost, and meanwhile, the 316L austenitic stainless steel is not resistant to seawater corrosion; on the other hand, on the alloy material of the pump valve of the marine vessel, the adhesion problem of marine microorganisms after the pump valve is used for a long time is generally not considered in the market, so on the basis of considering seawater corrosion resistance, the problems of pump valve blockage possibly caused by the long-time adhesion of the marine organisms and service life reduction caused by microbial corrosion should be considered. In view of the defects of the alloy material for the ship pump valve in the current market, the copper alloy material for the pump valve in the current market has the problems of high price, poor cutting processability of 316L stainless steel and the like, the invention provides a brand-new alloy material for the ship pump valve, meets the requirements on comprehensive performances such as seawater corrosion resistance, easy cutting, marine organism adhesion prevention and the like through the control of alloy components and the design of a heat treatment process, and becomes a technical problem to be solved urgently.

Disclosure of Invention

The invention aims to solve the problems in the prior art and provide an antimicrobial adhesion seawater corrosion resistant duplex stainless steel for a ship pump valve, and a preparation method and application thereof.

In order to achieve the purpose of the invention, the invention adopts the following technical scheme:

an antimicrobial adhesion seawater corrosion resistant duplex stainless steel for a ship pump valve comprises the following alloy components in percentage by mass: less than or equal to 0.03 percent of C, less than or equal to 0.03 percent of S, less than or equal to 0.04 percent of P, less than or equal to 0.20 percent of N, 19.00 to 24.00 percent of Cr, 2.0 to 4.00 percent of Cu, Ni: 3.00-4.50%, Mo: 0.3-1.0%, and the balance of iron and inevitable other impurities.

As the preferred technical scheme of the invention, the marine pump valve antimicrobial adhesion seawater corrosion resistant duplex stainless steel comprises the following components in percentage by mass: c: 0.010-0.02%, S is less than or equal to 0.008%, P is less than or equal to 0.04%, N: 0.002 to 0.15%, 19.50 to 22.60% of Cr, 2.50 to 3.5% of Cu, Ni: 3.00-3.50%, Mo: 0.4-0.8%, and the balance of iron and inevitable impurities.

As a further preferred technical scheme of the invention, the marine pump valve antimicrobial adhesion seawater corrosion resistant duplex stainless steel comprises the following components in percentage by mass: c: 0.010-0.012%, S: 0.005-0.006%, P is less than or equal to 0.04%, N: 0.002-0.131%, 19.54-19.57% of Cr, 2.63-2.78% of Cu, Ni: 3.18-3.24%, Mo: 0.41-0.45%, and the balance of iron and inevitable impurities.

As a preferred technical scheme of the invention, the alloy element Cu in the antimicrobial adhesion seawater corrosion resistant duplex stainless steel for the ship pump valve is dispersed and separated out from a material matrix in a-Cu phase and is uniformly distributed, wherein the-Cu phase size is 80-150 nm, and the material hardness value is 30-40 HRC.

The invention relates to application of an antimicrobial adhesion seawater corrosion resistant duplex stainless steel for a marine pump valve.

The invention discloses a preparation method of an antimicrobial adhesion seawater corrosion resistant duplex stainless steel for a marine pump valve, which comprises the following steps:

a. preparing raw materials:

weighing the following raw materials in percentage by mass:

c is less than or equal to 0.03 percent, S is less than or equal to 0.03 percent, P is less than or equal to 0.04 percent, N: 0.00-0.20%, 19.00-24.00% of Cr, 2.00-4.00% of Cu, and Ni: 3.00-4.50%, Mo: 0.30-1.00% of iron for later use;

b. the casting processing casting process comprises the following steps:

smelting the raw materials taken in the step a by a medium-frequency induction furnace or an electric furnace, and then preparing pump valve castings for marine ships by a series of processes such as AOD smelting, casting, heat treatment, turning forming, welding and the like;

c. the post-treatment process for heat treatment strengthening comprises the following steps:

and c, carrying out solution treatment on the pump valve casting prepared in the step b in a high-temperature two-phase region, then carrying out primary aging treatment and secondary aging treatment at a low temperature, obtaining a material with a ferrite-austenite duplex structure through a heat preservation solution treatment process, and simultaneously precipitating alloy element Cu added in the material from a matrix in a Cu phase in the heat preservation aging treatment process so as to obtain the antimicrobial adhesion seawater corrosion resistant duplex stainless steel for the pump valve of the ship. The ferrite-austenite dual-phase structure is obtained through treatment, and the hardness is improved, so that the cutting processing performance of the material is improved; meanwhile, in the process of heat preservation and aging, the alloy element Cu added in the material is precipitated from the matrix in a-Cu phase, so that the processing performance is further improved, and the capability of resisting bacteria and preventing microorganism adhesion is obtained.

As a preferable technical scheme of the invention, in the step a, the raw materials are weighed according to the following mass percentage: c: 0.010-0.02%, S is less than or equal to 0.008%, P is less than or equal to 0.04%, N: 0.002 to 0.15%, 19.50 to 22.60% of Cr, 2.50 to 3.5% of Cu, Ni: 3.00-3.50%, Mo: 0.4-0.8% and the balance of iron.

As a preferable technical scheme of the invention, in the step c, heat preservation and aging treatment is carried out, the primary aging heat preservation time is not more than 2 hours, the secondary aging time is 2-8 hours, and the temperature for carrying out the heat preservation and aging treatment is controlled to be 300-800 ℃.

As a preferable technical scheme of the invention, in the step c, when the solution treatment is carried out in the high-temperature two-phase region, the temperature is controlled to be 1000-1200 ℃, and the solution treatment time is 0.5-2 h. The primary aging temperature and time are completely different from the secondary aging temperature and time so as to ensure that the hardness of the material is about 30-40 HRC. The control on the aging temperature and the heat preservation time is very important, the high temperature and the low temperature can not ensure the precipitation of a good two-phase structure and a copper-rich phase, the heat preservation time directly influences the antimicrobial adhesion performance and the mechanical performance of the copper-rich phase, and the mutual matching of the temperature and the time ensures that the precipitation size of a-Cu phase is about 80-150 nm.

Compared with the prior art, the invention has the following obvious and prominent substantive characteristics and remarkable advantages:

1. after the anti-microbial adhesion seawater corrosion resistant duplex stainless steel for the marine pump valve is subjected to solution treatment in a high-temperature two-phase region, primary aging treatment and secondary aging treatment are carried out at a low temperature, the hardness of the material is ensured to be about 30.0-40.0HRC, the structure and the hardness of the material are controlled to improve the machinability of the material, and meanwhile, the added alloy element Cu is dispersed and precipitated from a matrix in a Cu phase of 80-150 nm to play a role of resisting microbial adhesion on the surface;

2. the ship pump valve casting prepared by the method has higher strength, good seawater corrosion resistance and scouring resistance, and good cold processing performance, and can be widely applied to ship pump valves and other marine environment materials;

3. compared with the copper alloy and 316L pump valve material which are widely used in the market at present, the antimicrobial adhesion seawater corrosion resistant duplex stainless steel has the advantages that the cost is reduced on the premise of improving the performance, and the popularization and the use are easy.

Drawings

FIG. 1 is an electron microscope picture of the precipitation of copper-rich phase (-Cu) of the antimicrobial seawater corrosion resistant duplex stainless steel for pump valves according to the embodiment of the present invention.

FIG. 2 is a comparison of marine microorganism adhesion resistance test pictures of an antimicrobial seawater corrosion resistant duplex stainless steel for a pump valve according to the first embodiment and the second embodiment of the present invention and a duplex stainless steel for a comparative example solid solution state pump valve.

Detailed Description

The above-described scheme is further illustrated below with reference to specific embodiments, which are detailed below: