Material for repairing damaged non-magnetic drill collar through laser cladding as well as preparation method and application of material

Abstract

The invention belongs to the field of laser material processing, and particularly relates to a material for repairing a damaged non-magnetic drill collar through laser cladding and a preparation method and application of the material. The invention discloses powder for repairing a non-magnetic drill collar through laser cladding. The powder comprises the following elements in percentage by mass: 12-15% of Cr, 15-18% of Mn, 1-3% of Ni, 0.1-0.3% of N and the balance of Fe. The surfacing alloy components are better matched with the non-magnetic weighted drill boat, the toughness of the surfacing alloy can be improved, and the bonding strength is also improved; and meanwhile, by changing the ratio of the repairing powder and adding sufficient powder components capable of opening an austenite phase region, the stability of the austenite phase region of an alloy system is ensured, meanwhile, a ferrite phase region is reduced, and part of alpha ferrite is promoted to be converted into austenite and a non-magnetic Fe-Cr-N intermetallic compound. The laser cladding layer with low relative permeability is prepared, the hardness of the laser cladding layer is high, the laser cladding layer can be well combined with a repairing base body, no obvious crack exists, and the repaired damaged non-magnetic drill collar can meet the requirement for descending a well again.

Description

Technical Field

[0001] The present application belongs to the field of laser material processing, and specifically relates to a material for laser cladding repair of damaged non-magnetic drill collars, and a preparation method and application thereof. Background Art

[0002] In directional exploration, non-magnetic drill collars create an environment without magnetic interference for the measurement while drilling device, ensuring the wellbore orientation, drilling trajectory and verticality. At present, most non-magnetic drills use high-wall thickness non-magnetic steel (austenitic stainless steel such as Cr-Ni, Cr-Mn, etc.) with a magnetic permeability lower than 1.010 to meet the precision requirements of directional exploration. Therefore, the material of non-magnetic drill collars is mostly austenitic stainless steel, which has poor wear resistance. Secondly, the service environment of non-magnetic drill collars is mostly in the open hole section, and the frequency of use is high. Therefore, the wear rate of non-magnetic drill collars is much higher than that of ordinary drilling tools. For failed non-magnetic drill boats, the drilling and production process generally adopts the method of downgrading or even scrapping, resulting in high drilling and production costs.

[0003] Based on the current construction situation that the loss cost of non-magnetic drill collars accounts for a huge proportion of the drilling project, the research on the repair technology of non-magnetic drilling rigs can make the failed non-magnetic drill collars meet the conditions for re-entering the well, which has significant economic benefits and engineering value for the drilling platform.

[0004] Laser cladding repair and remanufacturing is an advanced repair technology with many unique features that can be used to restore the function of damaged non-magnetic drill collars. It has many advantages such as high precision, low thermal impact, multi-material compatibility, high efficiency, etc. It can achieve highly accurate material addition and almost accurately restore the original size and geometry of parts. Unlike traditional surfacing methods, the heat affected zone of laser cladding repair is very small, so it will not cause obvious thermal deformation or stress to the surrounding materials. The laser cladding repair powder formula has a wide range of adjustable ingredients and can be used for different types of materials, including metals, ceramics and composite materials, so it has a wide range of applications. In general, laser cladding repair is a mature technology suitable for non-magnetic drill repair and remanufacturing. It is of great significance for repairing key components of oil drilling and extending their service life.

[0005] The development of non-magnetic powder formula is the key to repairing damaged non-magnetic drill tools by laser cladding. In order to ensure that the cladding repair alloy has special properties similar to those of the repaired non-magnetic drill tools, such as wear resistance and non-magnetic properties, the main chemical composition of the cladding alloy should be roughly the same as that of the non-magnetic drill tool base material. Usually, the presence of chromium (Cr) in the alloy composition will cause the stainless steel to have a magnetic crystal structure. Another component, nickel (Ni), will inhibit the generation of this magnetism. The non-magnetic weighted drilling boats with the grades W1813N and W2014N that are widely used in China adopt the composition design idea of ​​replacing Ni with Mn, and the Ni content is less than 2%. However, the performance of the cladding metal often cannot achieve the non-magnetic properties of the forged non-magnetic steel with the same composition.

[0006] In terms of wear performance, the cooling rate of laser cladding metal is relatively fast (about 106℃ / s), and the temperature of the cladding layer can quickly drop to about 200℃ within 10s after the heat source is removed. It is easy to have interface bonding strength mismatch, leading to cracking, and there are problems such as shedding during wear, and the wear resistance is insufficient. In terms of non-magnetic properties, the cooling rate of laser cladding metal is relatively fast. Cooling under non-equilibrium solidification conditions can easily lead to the presence of magnetic BCC intermediate phases (such as Fe-Cr ferrite α phase) in the laser cladding layer, which in turn affects the relative permeability stability of the non-magnetic drill after repair. Summary of the invention

[0007] In view of the problems existing in the application of laser cladding repair in the repair of non-magnetic drill collars at this stage, this application designs a Fe-Cr-Mn series laser cladding powder for repairing non-magnetic drill collars, so that its cladding alloy composition is more compatible with the non-magnetic weighted drill boat, which can improve the toughness of the cladding alloy and improve the bonding strength; at the same time, by changing the repair powder ratio, adding a sufficient amount of powder components that can open the austenite phase region, ensuring the stability of the austenite phase region of the alloy system, and reducing the ferrite phase region, prompting part of the α-ferrite to transform into austenite and non-magnetic Fe-Cr-N intermetallic compounds. The method provided by the present invention can be used to prepare a laser cladding layer with a low relative magnetic permeability, which has a high hardness and good bonding with the repair substrate without obvious cracks. The repaired damaged non-magnetic drill collar can meet the needs of re-entering the well.

[0008] A material for laser cladding to repair a damaged non-magnetic drill collar comprises the following elements in percentage by mass: Cr: 12-15wt%, Mn: 15-18wt%, Ni: 1-3wt%, N: 0.1-0.3wt%, and the balance Fe.

[0009] Preferably, the following elements are included in mass percentage: Cr: 14wt%, Mn: 17wt%, Ni: 3wt%, N: 0.3wt%, and the balance is Fe.

[0010] On the other hand, the preparation method of the material for repairing the damaged non-magnetic drill collar by laser cladding comprises the following steps:

[0011] (1) Gas atomization powder making: Mix and melt the components according to the proportion, and then use inert gas to gasify the metal droplets;

[0012] (2) Screening: Screening the powder obtained by aerosolization powder making in step (1);

[0013] (3) Drying: The powder screened in step (2) is vacuum dried to obtain the product.

[0014] Furthermore, the raw materials of step (1) are Fe, Cr, Mn, Ni metal powders and CrN ceramic powders with a purity of ≥99.5%;

[0015] The smelting conditions are: smelting temperature of 1600-1650°C, smelting pressure of 0.6-0.8Mpa; and / or

[0016] The sieving conditions in step (2) are: obtaining a powder with an average particle size of 53-150 μm; and / or

[0017] The conditions of vacuum drying in step (3) are as follows: the drying temperature is set at 110-120°C, the drying time is set at 3-5 hours, and the vacuum degree is set at -1.0×10 5 Pa.

[0018] Furthermore, the inert gas in step (1) is Ar gas with a purity of ≥99.99%; and / or

[0019] The atomization pressure is 6-8Mpa.

[0020] On the other hand, the material for repairing damaged non-magnetic drill collars by laser cladding and the material for repairing damaged non-magnetic drill collars by laser cladding prepared by the preparation method are used in repairing damaged non-magnetic drill collars.

[0021] Furthermore, the application comprises the following steps:

[0022] S1: Grind and clean the damaged part of the workpiece to be repaired, and perform a laser air scanning procedure on the repaired area after grinding and cleaning;

[0023] S2 uses the above-mentioned laser cladding non-magnetic drill collar repair material and the laser cladding non-magnetic drill collar repair material prepared by the above-mentioned preparation method to laser clad the damaged part of the non-magnetic drill collar damaged workpiece.

[0024] Furthermore, the method further includes step S0 of conducting a comprehensive inspection on the damaged non-magnetic drill collar, determining the damage form of the damaged surface, and using machining to remove the areas to be repaired with cracks, clamping marks and wear on the surface of the non-magnetic drill collar, while retaining the non-magnetic alloy in other undamaged areas.

[0025] Furthermore, in step S1, the process parameters of the laser scanning are as follows: laser power is 200-300W, scanning rate is 1000-1300mm / min, scanning spacing is 0.5-1mm; and / or

[0026] In step S2, the process parameters of laser cladding repair are as follows: laser power is 1500-1700W, scanning rate is 500-800mm / min, scanning spacing is 1mm, scanning layer thickness is 0.5mm, powder feeding rate is 1300-1700mm 3 / min, and the powder delivery gas flow rate is 6-8L / min.

[0027] Beneficial effects of this application

[0028] (1) The Fe-Cr-Mn powder used for laser cladding repair of non-magnetic drill collars has a cladding alloy composition that is more compatible with non-magnetic weighted drill bits, which can improve the toughness of the cladding alloy and increase the bonding strength. At the same time, by changing the repair powder ratio, sufficient amounts of Cr and Mn can be added to open the austenite phase region, ensuring the stability of the austenite phase region of the alloy system, tending to form a stable, low magnetic permeability laser cladding layer, and then by introducing a trace amount of N elements, the residual magnetic phase in the cooling process of the cladding metal can be eliminated.

[0029] (2) The laser cladding non-magnetic drill collar repair powder and the laser cladding layer preparation method provided by the present invention can obtain a non-magnetic laser cladding layer with a relative magnetic permeability lower than 1.010, which is suitable for repairing damaged iron-based non-magnetic drill collars of grades such as P530, W1813N and N1310B.

[0030] (3) The repaired area of ​​the non-magnetic drill collar repaired by the laser cladding repair powder of the present invention has no obvious cracking phenomenon, and its structure is high manganese austenite. The non-magnetic drill collar after laser cladding repair can obtain the performance conditions for re-entry into the well. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the XRD spectrum of the laser cladding repair layer with high manganese austenite structure prepared by the present invention;

[0032] Figure 2 VSM curves of the laser cladding repair layer with a relative magnetic permeability lower than 1.010 and the laser cladding repair layer without N prepared by the present invention;

[0033] Figure 3The metallographic image of the laser cladding repair layer prepared by the present invention and having a relative magnetic permeability lower than 1.010;

[0034] Figure 4 The hardness data of the laser cladding repair layer prepared in the embodiment of the present invention;

[0035] Figure 5 The tensile strength data of the laser cladding repair layer prepared in the embodiment of the present invention;

[0036] Figure 6 This is the actual situation of the surface cladding test of the non-magnetic drilling boat. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with specific embodiments, but they do not constitute any limitation to the present invention.

[0038] Example 1

[0039] The application of laser cladding non-magnetic drill collar repair material in non-magnetic drill collar repair includes the following steps:

[0040] Step 1: Perform a comprehensive inspection on the damaged non-magnetic drill collar to determine the damage form of the damaged surface, and use machining to remove the areas to be repaired with cracks, clamping injuries and wear on the surface of the non-magnetic drill collar, and retain the non-magnetic alloy in other undamaged areas; the damaged part of the non-magnetic drill tool in this embodiment is P530 stainless steel, and the size of the damaged part is about 25×25×10mm 3 .

[0041] Step 2: Grind and clean the damaged parts after machining, and perform a laser air scanning procedure on the repaired area after grinding and cleaning; the laser power is 250W, the scanning rate is 1200mm / min, and the scanning interval is 1mm.

[0042] Step 3: Use repair powder to perform laser cladding repair on the damaged parts of the non-magnetic drill collar damaged workpiece. The specific parameters are as follows: laser power is 1700W, scanning rate is 800mm / min, scanning spacing is 1mm, scanning layer thickness is 0.5mm, and powder feeding rate is 1700mm. 3 / min, and the powder feeding gas flow rate is 6L / min.

[0043] The main components of the repair powder of this embodiment are Fe: 65.7wt%, Cr: 14wt%, Mn: 17wt%, Ni: 3wt%, and N: 0.3wt%.

[0044] Laser cladding powder preparation method of this embodiment:

[0045] ① Gas atomization powder making: The raw material ratio is composed of the following components by mass percentage: chromium powder: 13.2%, manganese powder: 17%, nickel powder: 3%, chromium nitride powder 1.3%, iron powder: balance; each component is added into a vacuum melting furnace according to the ratio, the temperature in the melting furnace is set to 1625℃, and the pressure in the melting furnace is set to 0.7Mpa; then, Ar gas with a purity of ≥99.99% is used to gas atomize the metal droplets, and the gas atomization pressure is 6Mpa;

[0046] ②Sieving: Sieving the powder obtained by aerosol powdering in step ① to obtain a powder with an average particle size of 53-150 μm;

[0047] ③ Drying: The powder after screening in step ② is vacuum dried, the drying temperature is set to 110-120℃, the drying time is set to 3-5 hours, and the vacuum degree is set to -1.0×10 5 Pa.

[0048] Example 2

[0049] The application of laser cladding non-magnetic drill collar repair material in non-magnetic drill collar repair includes the following steps:

[0050] Step 1: Perform a comprehensive inspection on the damaged non-magnetic drill collar to determine the damage form of the damaged surface, and use machining to remove the areas to be repaired with cracks, clamping injuries and wear on the surface of the non-magnetic drill collar, and retain the non-magnetic alloy in other undamaged areas; the damaged part of the non-magnetic drill tool in this embodiment is P530 stainless steel, and the size of the damaged part is about 25×25×20mm 3 .

[0051] Step 2: Grind and clean the damaged parts after machining, and perform a laser air scanning procedure on the repaired area after grinding and cleaning; the laser power is 250W, the scanning rate is 1200mm / min, and the scanning interval is 1mm.

[0052] Step 3: Use repair powder to perform laser cladding repair on the damaged parts of the non-magnetic drill collar damaged workpiece. The specific parameters are as follows: laser power is 1600W, scanning rate is 650mm / min, scanning spacing is 1mm, scanning layer thickness is 0.5mm, and powder feeding rate is 1500mm 3 / min, and the powder feeding gas flow rate is 6L / min.

[0053] The main components of the repair powder of this embodiment are Fe: 65.7wt%, Cr: 14wt%, Mn: 17wt%, Ni: 3wt%, and N: 0.3wt%.

[0054] Laser cladding powder preparation method of this embodiment:

[0055] The mass fraction ratio of the raw materials is: chromium powder: 13.2%, manganese powder: 17%, nickel powder: 3%, chromium nitride powder: 1.3%, iron powder: balance;

[0056] The rest is the same as ①② and ③ in Example 1.

[0057] Example 3

[0058] The application of laser cladding non-magnetic drill collar repair material in non-magnetic drill collar repair includes the following steps:

[0059] Step 1: Perform a comprehensive inspection on the damaged non-magnetic drill collar to determine the damage form of the damaged surface, and use machining to remove the areas to be repaired with cracks, clamping injuries and wear on the surface of the non-magnetic drill collar, and retain the non-magnetic alloy in other undamaged areas; the damaged part of the non-magnetic drill tool in this embodiment is P530 stainless steel, and the size of the damaged part is about 25×25×30mm 3 .

[0060] Step 2: Grind and clean the damaged parts after machining, and perform a laser air scanning procedure on the repaired area after grinding and cleaning; the laser power is 250W, the scanning rate is 1200mm / min, and the scanning interval is 1mm.

[0061] Step 3: Use repair powder to perform laser cladding repair on the damaged parts of the non-magnetic drill collar damaged workpiece. The specific parameters are as follows: laser power is 1500W, scanning rate is 500mm / min, scanning spacing is 1mm, scanning layer thickness is 0.5mm, and powder feeding rate is 1300mm. 3 / min, and the powder feeding gas flow rate is 6L / min.

[0062] The main components of the repair powder of this embodiment are Fe: 65.7wt%, Cr: 14wt%, Mn: 17wt%, Ni: 3wt%, and N: 0.3wt%.

[0063] Laser cladding powder preparation method of this embodiment:

[0064] The mass fraction ratio of the raw materials is: chromium powder: 13.2%, manganese powder: 17%, nickel powder: 3%, chromium nitride powder: 1.3%, iron powder: balance;

[0065] The rest is the same as ①② and ③ in Example 1.

[0066] Example 4

[0067] The application of laser cladding non-magnetic drill collar repair material in non-magnetic drill collar repair includes the following steps:

[0068] Step 1: Perform a comprehensive inspection on the damaged non-magnetic drill collar to determine the damage form of the damaged surface, and use machining to remove the areas to be repaired with cracks, clamping injuries and wear on the surface of the non-magnetic drill collar, and retain the non-magnetic alloy in other undamaged areas; the damaged part of the non-magnetic drill tool in this embodiment is P530 stainless steel, and the size of the damaged part is about 25×25×20mm 3 .

[0069] Step 2: Grind and clean the damaged parts after machining, and perform a laser air scanning procedure on the repaired area after grinding and cleaning; the laser power is 200W, the scanning rate is 1300mm / min, and the scanning interval is 1mm.

[0070] Step 3: Use repair powder to perform laser cladding repair on the damaged parts of the non-magnetic drill collar damaged workpiece. The specific parameters are as follows: laser power is 1700W, scanning rate is 500mm / min, scanning spacing is 1mm, scanning layer thickness is 0.5mm, and powder feeding rate is 1300mm. 3 / min, and the powder feeding gas flow rate is 8L / min.

[0071] The main components of the repair powder are Fe: 65.9wt%, Cr: 15wt%, Mn: 18wt%, Ni: 1wt%, and N: 0.1wt%.

[0072] Laser cladding powder preparation method of this embodiment:

[0073] ① Gas atomization powder making: chromium powder: 14.7%, manganese powder: 18%, nickel powder: 1%, chromium nitride powder 0.4%, iron powder: balance; add each component into a vacuum melting furnace according to the proportion, set the temperature in the melting furnace to 1600℃, and set the pressure in the melting furnace to 0.6Mpa; then use Ar gas with a purity of ≥99.99% to gasify the metal droplets, and the gas atomization pressure is 6Mpa;

[0074] ②Sieving: Sieving the powder obtained by aerosol powdering in step ① to obtain a powder with an average particle size of 53-150 μm;

[0075] ③ Drying: The powder after screening in step ② was vacuum dried, the drying temperature was set to 110℃, the drying time was set to 5 hours, and the vacuum degree was set to -1.0×10 5 Pa.

[0076] Example 5

[0077] The application of laser cladding non-magnetic drill collar repair material in non-magnetic drill collar repair includes the following steps:

[0078] Step 1: Perform a comprehensive inspection on the damaged non-magnetic drill collar to determine the damage form of the damaged surface, and use machining to remove the areas to be repaired with cracks, clamping injuries and wear on the surface of the non-magnetic drill collar, and retain the non-magnetic alloy in other undamaged areas; the damaged part of the non-magnetic drill tool in this embodiment is P530 stainless steel, and the size of the damaged part is about 25×25×20mm 3 .

[0079] Step 2: Grind and clean the damaged parts after machining, and perform a laser air scanning procedure on the repaired area after grinding and cleaning; the laser power is 300W, the scanning rate is 1000mm / min, and the scanning interval is 1mm.

[0080] Step 3: Use repair powder to perform laser cladding repair on the damaged parts of the non-magnetic drill collar damaged workpiece. The specific parameters are as follows: laser power is 1500W, scanning rate is 800mm / min, scanning spacing is 1mm, scanning layer thickness is 0.5mm, and powder feeding rate is 1700mm. 3 / min, and the powder feeding gas flow rate is 6L / min.

[0081] The main components of the repair powder are Fe: 70.8wt%, Cr: 12wt%, Mn: 15wt%, Ni: 2wt%, and N: 0.2wt%.

[0082] Laser cladding powder preparation method of this embodiment:

[0083] ① Gas atomization powder making: The mass fraction ratio of the raw materials is: chromium powder: 11.4%, manganese powder: 15%, nickel powder: 2%, chromium nitride powder 0.8%, iron powder: balance; add each component into a vacuum melting furnace according to the ratio, set the temperature in the melting furnace to 1650℃, and set the pressure in the melting furnace to 0.8Mpa; then use Ar gas with a purity of ≥99.99% to gasify the metal droplets, and the gas atomization pressure is 8Mpa;

[0084] ②Sieving: Sieving the powder obtained by aerosol powdering in step ① to obtain a powder with an average particle size of 53-150 μm;

[0085] ③ Drying: The powder after screening in step ② was vacuum dried, the drying temperature was set to 120℃, the drying time was set to 3 hours, and the vacuum degree was set to -1.0×10 5 Pa.

[0086] Comparative Example 1

[0087] Compared with Example 1, N is not added. Specifically, the main components of the repair powder are Fe: 65.7wt%, Cr: 14wt%, Mn: 17wt%, and Ni: 3wt%.

[0088] The preparation method of laser cladding powder in this comparative example: the mass fraction ratio of raw materials is: chromium powder: 14%, manganese powder: 17%, nickel powder: 3%, iron powder: balance;

[0089] The rest is the same as ①② and ③ in Example 1.

[0090] The steps of applying Comparative Example 1 to repairing non-magnetic drill collars are the same as Step 1, Step 2 and Step 3 in Example 1.

[0091] Comparative Example 2

[0092] Compared with Example 5, N is not added. Specifically, the main components of the repair powder are Fe: 70.8wt%, Cr: 12wt%, Mn: 15wt%, and Ni: 2wt%.

[0093] The ratio of raw materials is: The laser cladding powder preparation method of this comparative example: the mass fraction ratio of raw materials is: chromium powder: 12%, manganese powder: 15%, nickel powder: 2%, iron powder: balance;

[0094] The rest is the same as ①② and ③ in Example 55.

[0095] The steps of applying Comparative Example 2 to repairing non-magnetic drill collars are the same as Step 1, Step 2 and Step 3 in Example 5.

[0096] Implementation effect example

[0097] Figure 1 is the XRD spectrum of the laser cladding repair layer with high manganese austenite structure prepared in the embodiment of the present invention, Figure 1 It can be seen that the laser cladding repair area of ​​this embodiment is an austenite phase; Figure 2 is a VSM curve of the laser cladding repair layer with a relative magnetic permeability lower than 1.010 prepared in the embodiment of the present invention, Figure 2 It can be seen that the laser cladding layer without N in the comparative example has a higher relative magnetic permeability, while the magnetic curve of the laser cladding layer of this embodiment has paramagnetic characteristics, and the corresponding relative magnetic permeability test results are all less than 1.010; Figure 3 The metallographic image of the laser cladding repair layer with a relative magnetic permeability lower than 1.010 prepared in the embodiment of the present invention is shown in FIG. Figure 3 It can be seen that the structure of the repaired area of ​​the laser cladding layer in this embodiment is austenite without obvious crack defects; Figure 4 is the hardness data of the laser cladding repair layer in the embodiment of the present invention, Figure 4 It can be seen that the average hardness of the repaired area of ​​the laser cladding layer in this embodiment is greater than 20.8HRC, reaching more than 80% of the hardness of the parent material (P530); Figure 5 is the tensile strength data of the laser cladding repair layer in the embodiment of the present invention, Figure 5It can be seen that the average tensile strength Rm of the repaired area of ​​the laser cladding layer in this embodiment is greater than 535 MPa, reaching more than 70% of the tensile strength of the parent material (P530).

[0098] Therefore, the laser cladding non-magnetic drill collar repair material and its preparation method and corresponding repair powder provided in Examples 1-5 have mature processes. The method provided by the present invention can be used to prepare a high-manganese iron-based cladding layer, whose relative magnetic permeability is lower than 1.010, and has good bonding with the non-magnetic drill collar matrix without obvious cracks. The microstructure of the cladding layer is composed of austenite columnar dendrites growing vertically from the interface. The hardness of the cladding layer reaches more than 80% of the parent material P530, and the tensile strength reaches more than 70% of the parent material. The repaired damaged non-magnetic drill collar can meet the needs of re-entering the well.

[0099] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein, on the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A material for laser cladding to repair damaged non-magnetic drill collars. It is characterized in that The alloy comprises the following elements in percentage by mass: Cr: 12-15wt%, Mn: 15-18wt%, Ni: 1-3wt%, N: 0.1-0.3wt%, and the balance Fe.

2. A method for preparing the material for laser cladding repair of damaged non-magnetic drill collars according to claim 1, It is characterized in that The following steps are involved: (1) Gas atomization powder making: Mix and melt the components according to the proportion, and then use inert gas to gasify the metal droplets; (2) Screening: Screening the powder obtained by aerosolization powder making in step (1); (3) Drying: The powder screened in step (2) is vacuum dried to obtain the product.

3. The preparation method according to claim 2, It is characterized in that The raw materials corresponding to the components include: Fe, Cr, Mn, Ni metal powders with a purity of ≥99.5%, CrN ceramic powders with a purity of ≥99.5%; and / or The smelting conditions are: smelting temperature is 1600-1650°C, and smelting pressure is 0.6-0.8Mpa.

4. The preparation method according to claim 2, It is characterized in that The sieving conditions in step (2) are: obtaining a powder with an average particle size of 53 to 150 μm; and / or The conditions of vacuum drying in step (3) are as follows: drying temperature is 110-120°C, drying time is 3-5 hours, vacuum degree is -1.0×10 4 Pa~-1.0×10 5 Pa.

5. The preparation method according to claims 2-4, It is characterized in that In step (1), the inert gas is Ar gas with a purity of ≥99.99%; and / or The atomization pressure is 6-8Mpa.

6. Use of the material for repairing damaged non-magnetic drill collars by laser cladding as claimed in claim 1 or the material for repairing damaged non-magnetic drill collars by laser cladding as prepared by any one of the preparation methods described in claims 2 to 5 in repairing damaged non-magnetic drill collars.

7. The use according to claim 6, It is characterized in that The application comprises the following steps: S1: Grind and clean the damaged part of the workpiece to be repaired, and perform a laser air scanning procedure on the repaired area after grinding and cleaning; S2 uses the laser cladding non-magnetic drill collar repair material to perform laser cladding repair on the damaged part of the non-magnetic drill collar damaged workpiece.

8. The use according to claim 7, It is characterized in that The method also includes step S0 of comprehensively inspecting the damaged non-magnetic drill collar, determining the damage form of the damaged surface, and using machining to remove the areas to be repaired with cracks, clamping marks and wear on the surface of the non-magnetic drill collar, while retaining the non-magnetic alloy in other undamaged areas.

9. The use according to claim 7 or 8, It is characterized in that In step S1, the process parameters of laser scanning are as follows: laser power is 200-300 W, scanning rate is 1000-1300 mm / min, and scanning spacing is 0.5-1 mm.

10. The use according to claim 7 or 8, It is characterized in that In step S2, the process parameters of laser cladding repair are as follows: laser power is 1500-1700W, scanning rate is 500-800mm / min, scanning spacing is 1mm, scanning layer thickness is 0.5mm, powder feeding rate is 1300-1700mm 3 / min, and the powder feeding gas flow rate is 6~8L / min.

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