阅读说明：本技术 一种喷涂材料及基于热喷涂预处理的高氮钢焊接工艺 (Spraying material and high-nitrogen steel welding process based on thermal spraying pretreatment ) 是由 崔博 黄初焕 张龙 冯明佳 罗添文 孙丽娜 吕尤 王莉婷 李享 于 2021-09-02 设计创作，主要内容包括：一种喷涂材料及基于热喷涂预处理的高氮钢焊接工艺,涉及高氮钢焊接工艺领域,该喷涂材料由21％wt Cr、69％wt Mn、3％wt TiN和7％wt Ni组成。焊接工艺包括：配制喷涂材料并雾化处理；对高氮钢焊接坡口处进行打磨、吹砂,利用热喷涂方法将喷涂材料喷涂在高氮钢焊接坡口处；对经热喷涂处理后的高氮钢进行高能束焊接。本发明通过在高氮钢焊接坡口处预置合金涂层,减少焊接时母材熔化量,同时合金涂层的成分可有效提高氮在钢中的溶解度,从而解决焊缝氮含量减少、氮化物析出及析出型气孔缺陷等问题。本发明采用热喷涂预处理的方法在高氮钢焊接坡口处预置合金涂层,提高了工作效率,并且涂层分布均匀,不易脱落。(A spraying material and a high-nitrogen steel welding process based on thermal spraying pretreatment relate to the field of high-nitrogen steel welding processes, and the spraying material is composed of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni. The welding process comprises the following steps: preparing a spraying material and carrying out atomization treatment; polishing and sand blowing are carried out on the high-nitrogen steel welding groove, and a spraying material is sprayed on the high-nitrogen steel welding groove by a thermal spraying method; and carrying out high-energy beam welding on the high-nitrogen steel subjected to the thermal spraying treatment. According to the invention, the alloy coating is preset at the welding groove of the high-nitrogen steel, so that the melting amount of the base metal during welding is reduced, and meanwhile, the components of the alloy coating can effectively improve the solubility of nitrogen in the steel, thereby solving the problems of reduced nitrogen content of a welding seam, nitride precipitation, precipitation type pore defects and the like. The alloy coating is preset at the welding groove of the high-nitrogen steel by adopting a thermal spraying pretreatment method, so that the working efficiency is improved, and the coating is uniformly distributed and is not easy to fall off.)

1. A spray material characterized by consisting of 21% by weight of Cr, 69% by weight of Mn, 3% by weight of TiN and 7% by weight of Ni.

2. The high nitrogen steel welding process based on thermal spraying pretreatment realized by using the spraying material of claim 1, is characterized by comprising the following steps:

step one, preparation of spraying material

The spraying material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni, and the spraying material is atomized;

step two, pretreatment

Polishing and sand blowing are carried out on the high-nitrogen steel welding groove, and a spraying material is sprayed on the high-nitrogen steel welding groove by a thermal spraying method;

step three, high energy beam welding

And carrying out high-energy beam welding on the high-nitrogen steel subjected to the thermal spraying treatment.

3. The high nitrogen steel welding process based on thermal spraying pretreatment according to claim 2, characterized in that in the first step, the spraying material is atomized to control the particle size within 0.1 mm.

4. The high-nitrogen steel welding process based on thermal spraying pretreatment according to claim 2, wherein in the second step, the thermal spraying method is a flame spraying treatment method.

5. The high nitrogen steel welding process based on thermal spraying pretreatment according to claim 2, wherein in the second step, the spraying thickness of the spraying material is 0.3-0.6 mm.

6. The high nitrogen steel welding process based on thermal spray pretreatment according to claim 2, characterized in that in step three, the welding heat source of the high energy beam welding is a laser beam or an electron beam.

Technical Field

The invention relates to the technical field of high-nitrogen steel welding processes, in particular to a spraying material and a high-nitrogen steel welding process based on thermal spraying pretreatment.

Background

High-nitrogen austenitic stainless steel, called high-nitrogen steel for short, is a novel engineering material with the characteristics of high strength, high toughness, large creep resistance, good corrosion resistance and the like, and is concerned in recent years. The content of N in the high-nitrogen steel is generally more than 0.4%, and the welding performance of the high-nitrogen steel is widely concerned by the industry because the nitrogen content is high and the defects of nitrogen loss, nitride precipitation, welding pores and the like are easy to appear in a welding seam.

The Chinese patent with publication number CN105772944A discloses a welding device and a welding method for solving the problem of high-nitrogen steel welding air holes and improving the joint strength, and provides a new method for high-nitrogen steel laser-arc welding, which solves the problem of poor performance of the high-nitrogen steel welding air holes and the weld joint by using a magnetic control and temperature control composite method. Chinese patent publication No. CN106346171A discloses a "high-nitrogen steel pressure welding device and a method for welding high-nitrogen steel by using the same", which provides a welding method for reducing nitrogen content loss in a high-nitrogen steel weld and improving mechanical properties of the high-nitrogen steel weld by controlling the composition of welding shielding gas, welding pressure and cooling parameters during welding. The high-nitrogen steel welding methods have the problems of complicated process, complex welding device and the like, and can not solve the problems of nitrogen holes of welding seams, reduction of nitrogen content and the like. The article "research on weld nitrogen increase and joint structure performance of high-nitrogen steel MIG welding, Liu' on, Harbin industry university, 2015-07-01" provides a high-nitrogen steel MIG welding nitrogen increase method, which utilizes a self-made MnN welding wire to improve the nitrogen content of a weld, but the effect of improving the solubility of nitrogen elements by using Mn alone is limited, and the method is difficult to solve the defect of weld pores, and the MnN welding wire is also difficult to ensure the welding stability.

Disclosure of Invention

The invention provides a spraying material and a high-nitrogen steel welding process based on thermal spraying pretreatment, aiming at solving the problems of reduced nitrogen content of a welding seam, nitride precipitation, precipitation of type pores and the like in the existing high-nitrogen steel welding method.

The technical scheme adopted by the invention for solving the technical problem is as follows:

the spray coating material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni.

The high-nitrogen steel welding process based on thermal spraying pretreatment realized by adopting the spraying material mainly comprises the following steps of:

step one, preparation of spraying material

The spraying material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni, and the spraying material is atomized;

step two, pretreatment

Polishing and sand blowing are carried out on the high-nitrogen steel welding groove, and a spraying material is sprayed on the high-nitrogen steel welding groove by a thermal spraying method;

step three, high energy beam welding

And carrying out high-energy beam welding on the high-nitrogen steel subjected to the thermal spraying treatment.

In a preferred embodiment, in the first step, the spray material is atomized so that the particle diameter thereof is controlled to be within 0.1 mm.

In a preferred embodiment, in the second step, the thermal spraying method is a flame spraying treatment method.

In a preferred embodiment, in the second step, the spraying thickness of the spraying material is 0.3-0.6 mm.

In a preferred embodiment, in step three, the welding heat source for the high energy beam welding is a laser beam or an electron beam.

The invention has the beneficial effects that:

the invention relates to a high-nitrogen steel welding process based on thermal spraying pretreatment, which is characterized in that the thermal spraying pretreatment is carried out on a high-nitrogen steel welding groove in advance before welding, so that an alloy coating is formed at the high-nitrogen steel welding groove, the alloy coating is a special spraying material consisting of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni, and finally the high-nitrogen steel is welded by adopting a high-energy beam welding method such as laser beams or electron beams.

According to the invention, the alloy coating is preset at the welding groove of the high-nitrogen steel, so that the melting amount of the base metal during welding is reduced, and meanwhile, the components of the alloy coating can effectively improve the solubility of nitrogen in the steel, thereby solving the problems of reduced nitrogen content of a welding seam, nitride precipitation, precipitation type pore defects and the like.

The alloy coating is preset at the welding groove of the high-nitrogen steel by adopting a thermal spraying pretreatment method, so that the working efficiency is improved, and the coating is uniformly distributed and is not easy to fall off.

Drawings

Fig. 1 is a flaw detection diagram of a weld joint after welding by the high nitrogen steel welding process based on thermal spray pretreatment in example 1.

FIG. 2 is a flaw detection diagram of a weld seam welded by a conventional laser welding method.

Fig. 3 is a flaw detection diagram of a weld seam after welding by the high nitrogen steel welding process based on thermal spray pretreatment in example 2.

Fig. 4 is a flaw detection diagram of a weld joint welded by a conventional laser welding method.

Fig. 5 is a flaw detection diagram of a weld joint after welding by the high nitrogen steel welding process based on the thermal spray pretreatment in example 3.

FIG. 6 is a flaw detection diagram of a welded joint after welding by a conventional electron beam welding method.

Fig. 7 is a flaw detection diagram of a weld after welding by the high nitrogen steel welding process based on the thermal spray pretreatment in example 4.

FIG. 8 is a flaw detection diagram of a weld bead after welding by a conventional electron beam welding method.

Detailed Description

The spray coating material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni.

The invention relates to a high-nitrogen steel welding process based on thermal spraying pretreatment, which mainly comprises the following steps of:

step one, preparation of spraying material

The spray coating material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni, and is atomized to control the grain diameter within 0.1 mm.

Step two, pretreatment

And (3) polishing and blowing sand at the high-nitrogen steel welding groove, and spraying a spraying material at the high-nitrogen steel welding groove by using a flame spraying treatment method to form a spraying layer with the thickness of 0.3-0.6 mm.

Step three, high energy beam welding

And (3) performing high-energy beam welding on the high-nitrogen steel after the thermal spraying treatment, wherein a welding heat source for the high-energy beam welding can adopt a laser beam or an electron beam, but is not limited to the above.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1 high nitrogen steel welding process based on thermal spray pretreatment

1. Preparation of spray coating material

The spraying material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni, and is atomized, so that the grain size of the abrasive is controlled within 0.1 mm;

2. pretreatment of

2.1 removing surface oxidation films of two high-nitrogen steel plates with the thickness of 8.0mm and the nitrogen content of 0.62 percent by using an angle grinder, and then removing oil stains on the surface by using acetone;

2.2, performing refined sand blasting treatment on the high-nitrogen steel welding groove by adopting a suction sand blasting machine; the pressure of the suction sand blower is set to be 0.45MPa, and the sand blowing angle is set to be 30 degrees;

2.3 spraying a spraying material with the thickness of 0.5mm at the welding groove of the high-nitrogen steel by adopting a flame spraying treatment method.

3. High energy beam welding (laser welding)

3.1 assembling the two high-nitrogen steel plates after the thermal spraying treatment in a butt joint mode, vertically irradiating and welding the two high-nitrogen steel plates above the positions to be welded by using laser beams, wherein the defocusing amount of the laser beams is-2 mm, the laser power is 4.0kw, the welding speed is 0.8m/min, and the protective gas is argon.

As shown in FIG. 1, by using the welding method of the present embodiment, no air holes are formed at the welded seam after welding; and through the detection of a universal material testing machine, the tensile strength of a welding joint reaches 924.7Mpa, and can reach 88.1% of that of a base material; in addition, the weld joint is detected by a nitrogen-oxygen analyzer, and the nitrogen content of the weld joint can reach 0.55% by adopting the welding method of the embodiment.

As shown in figure 2, the existing laser welding method (two high nitrogen steel plates with the thickness of 8.0mm and the nitrogen content of 0.62 percent are used for removing surface oxide films by an angle grinder and then are used for removing oil stains on the surface by acetone, the two high nitrogen steel plates are assembled in a butt joint mode, laser beams are used for vertical irradiation welding above the positions to be welded of the two high nitrogen steel plates, the defocusing amount of the laser beams is-2 mm, the laser power is 4.0kw, the welding speed is 0.8m/min, the protective gas is argon gas), and more air holes are formed in the welding seams after welding; and through the detection of a universal material testing machine, the tensile strength of the welding joint is 820.3Mpa, which is 78.1% of that of the parent metal; in addition, the weld joint is detected by a nitrogen-oxygen analyzer, and the nitrogen content of the weld joint is 0.41 percent in the conventional laser welding method.

Example 2 high nitrogen steel welding process based on thermal spray pretreatment

1. Preparation of spray coating material

The spraying material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni, and is atomized, so that the grain size of the abrasive is controlled within 0.1 mm;

2. pretreatment of

2.1 removing surface oxidation films of two high-nitrogen steel plates with the thickness of 6.0mm and the nitrogen content of 0.62 percent by using an angle grinder, and then removing oil stains on the surface by using acetone;

2.2, performing refined sand blasting treatment on the high-nitrogen steel welding groove by adopting a suction sand blasting machine; the pressure of the suction sand blower is set to be 0.45MPa, and the sand blowing angle is set to be 30 degrees;

2.3 spraying a spraying material with the thickness of 0.4mm at the welding groove of the high-nitrogen steel by adopting a flame spraying treatment method.

3. High energy beam welding (laser welding)

3.1 assembling the two high-nitrogen steel plates after the thermal spraying treatment in a butt joint mode, vertically irradiating and welding the two high-nitrogen steel plates above the positions to be welded by using laser beams, wherein the defocusing amount of the laser beams is-2 mm, the laser power is 3.0kw, the welding speed is 0.8m/min, and the protective gas is argon.

As shown in FIG. 3, by using the welding method of the present embodiment, no air holes are formed at the welded seam after welding; and through the detection of a universal material testing machine, the tensile strength of a welding joint reaches 937.5Mpa, and can reach 89.3% of that of a base material; in addition, the weld joint is detected by a nitrogen-oxygen analyzer, and the nitrogen content of the weld joint can reach 0.57 percent by adopting the welding method of the embodiment.

As shown in FIG. 4, the existing laser welding method (two high nitrogen steel plates with thickness of 6.0mm and nitrogen content of 0.62% are used for removing surface oxide film by an angle grinder and then removing oil stain on the surface by acetone; the two high nitrogen steel plates are assembled in a butt joint mode, laser beams are used for vertical irradiation welding above the to-be-welded parts of the two high nitrogen steel plates, the defocusing amount of the laser beams is-2 mm, the laser power is 3.0kw, the welding speed is 0.8m/min, the protective gas is argon), and more pores are arranged at the welded joints after welding; and through the detection of a universal material testing machine, the tensile strength of the welding joint is 829.5Mpa which is 79 percent of the tensile strength of the parent metal; in addition, the weld joint is detected by a nitrogen-oxygen analyzer, and the nitrogen content of the weld joint is 0.43 percent in the conventional laser welding method.

Example 3 high nitrogen steel welding Process based on thermal spray pretreatment

1. Preparation of spray coating material

The spraying material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni, and is atomized, so that the grain size of the abrasive is controlled within 0.1 mm;

2. pretreatment of

2.1 removing surface oxidation films of two high-nitrogen steel plates with the thickness of 4.0mm and the nitrogen content of 0.62 percent by using an angle grinder, and then removing oil stains on the surface by using acetone;

2.2, performing refined sand blasting treatment on the high-nitrogen steel welding groove by adopting a suction sand blasting machine; the pressure of the suction sand blower is set to be 0.45MPa, and the sand blowing angle is set to be 30 degrees;

2.3 spraying a spraying material with the thickness of 0.3mm at the welding groove of the high-nitrogen steel by adopting a flame spraying treatment method.

3. High energy beam welding (Electron Beam welding)

3.1 assembling the two high-nitrogen steel plates subjected to thermal spraying treatment in a butt joint mode, performing electron beam welding by adopting electron beam welding equipment, wherein the acceleration voltage is 60kv, the working distance is 238mm, the welding beam current is 20mA, the focusing current is 715mA, and the welding speed is 6.5mm/s, and then taking out the workpiece to complete the electron beam welding of the high-nitrogen steel.

As shown in FIG. 5, by using the welding method of the present embodiment, no air holes are formed at the welded seam after welding; and through the detection of a universal material testing machine, the tensile strength of a welding joint reaches 945.3Mpa, and can reach 90% of that of a base material; in addition, the weld joint is detected by a nitrogen-oxygen analyzer, and the nitrogen content of the weld joint can reach 0.59 percent by adopting the welding method of the embodiment.

As shown in FIG. 6, the conventional electron beam welding method (two high nitrogen steel plates with thickness of 4.0mm and nitrogen content of 0.62% are assembled in a butt joint mode, electron beam welding is carried out by adopting electron beam welding equipment, the acceleration voltage is 60kv, the working distance is 238mm, the welding beam current is 20mA, the focusing current is 715mA, the welding speed is 6.5mm/s, then the workpiece is taken out, namely the electron beam welding of the high nitrogen steel is completed), and the air holes are more at the welding seam after welding; and through the detection of a universal material testing machine, the tensile strength of the welding joint is 836.9Mpa, which is 79.7% of that of the parent metal; in addition, the weld joint is detected by a nitrogen-oxygen analyzer, and the nitrogen content of the weld joint is 0.45 percent in the existing electron beam welding method.

Example 4 high nitrogen steel welding Process based on thermal spray pretreatment

1. Preparation of spray coating material

The spraying material consists of 21 wt% of Cr, 69 wt% of Mn, 3 wt% of TiN and 7 wt% of Ni, and is atomized, so that the grain size of the abrasive is controlled within 0.1 mm;

2. pretreatment of

2.1 removing surface oxidation films of two high-nitrogen steel plates with the thickness of 10.0mm and the nitrogen content of 0.62 percent by using an angle grinder, and then removing oil stains on the surface by using acetone;

2.2, performing refined sand blasting treatment on the high-nitrogen steel welding groove by adopting a suction sand blasting machine; the pressure of the suction sand blower is set to be 0.45MPa, and the sand blowing angle is set to be 30 degrees;

2.3 spraying a spraying material with the thickness of 0.6mm at the welding groove of the high-nitrogen steel by adopting a flame spraying treatment method.

3. High energy beam welding (Electron Beam welding)

3.1 assembling the two high-nitrogen steel plates subjected to thermal spraying treatment in a butt joint mode, carrying out electron beam welding by adopting electron beam welding equipment, wherein the acceleration voltage is 60kv, the working distance is 238mm, the welding beam current is 52mA, the focusing current is 1.92A, and the welding speed is 11.5mm/s, and then taking out the workpiece to finish the electron beam welding of the high-nitrogen steel.

As shown in fig. 7, by using the welding method of the present embodiment, no air holes are formed at the welded joint after welding; and through the detection of a universal material testing machine, the tensile strength of a welding joint reaches 940.2Mpa, and can reach 89.5% of that of a base material; in addition, the weld joint is detected by a nitrogen-oxygen analyzer, and the nitrogen content of the weld joint can reach 0.57 percent by adopting the welding method of the embodiment.

As shown in FIG. 8, in the conventional electron beam welding method (two high nitrogen steel plates with the thickness of 10.0mm and the nitrogen content of 0.62 percent are subjected to surface oxidation film removal by an angle grinder and then are subjected to surface oil stain removal by acetone, the two high nitrogen steel plates are assembled in a butt joint mode and are subjected to electron beam welding by electron beam welding equipment, the acceleration voltage is 60kv, the working distance is 238mm, the welding beam current is 52A, the focusing current is 1.92A, the welding speed is 11.5mm/s, and then a workpiece is taken out, namely the electron beam welding of the high nitrogen steel is completed), and the air holes at the welding line are more after the welding; and the tensile strength of the welding joint is 841.6Mpa which is 80.2% of that of the parent metal detected by a universal material testing machine; in addition, the weld joint is detected by a nitrogen-oxygen analyzer, and the nitrogen content of the weld joint is 0.43 percent in the existing electron beam welding method.

The invention discloses a spraying material and a high-nitrogen steel welding process based on thermal spraying pretreatment, and the technical personnel in the field can realize the purpose by properly improving process parameters by referring to the content. It is expressly intended that all such similar substitutes and modifications which would be obvious to one skilled in the art are deemed to be included in the invention. While the invention has been described in terms of preferred embodiments, it will be apparent to those skilled in the art that the technology can be practiced and applied by modifying or appropriately combining the products described herein without departing from the spirit and scope of the invention.