阅读说明：本技术 一种镍基合金薄壁圆管的制备方法 (Preparation method of nickel-based alloy thin-wall circular tube ) 是由 马宽 李安 黄椿森 唐洪奎 瞿宗宏 赖运金 王庆相 梁书锦 张平祥 于 2019-09-25 设计创作，主要内容包括：本发明公开了一种镍基合金薄壁圆管的制备方法,具体为：首先称取合金粉末和氯化钠混合均匀,得到混合粉末；另外称取氯化钠,制备氯化钠圆棒；将混合粉末通过大气等离子喷涂法喷涂至匀速旋转的氯化钠圆棒表面；将带有涂层的氯化钠圆棒放入真空炉中,高温烧结；将带有涂层的氯化钠圆棒放入水中,使用超声波进行清洗,直至氯化钠圆棒溶解脱落,得到合金圆管,本发明采用高球形度高温合金粉末结合等离子喷涂方法制备多孔高温合金柱状薄壁圆管,工艺简单,管壁厚度可控,基体材料可回收重复利用。(The invention discloses a preparation method of a nickel-based alloy thin-wall circular tube, which comprises the following steps: firstly, weighing alloy powder and sodium chloride, and uniformly mixing to obtain mixed powder; in addition, sodium chloride is weighed to prepare a sodium chloride round bar; spraying the mixed powder on the surface of a sodium chloride round bar rotating at a constant speed by an atmospheric plasma spraying method; putting the sodium chloride round bar with the coating into a vacuum furnace, and sintering at high temperature; the porous high-temperature alloy cylindrical thin-wall circular tube is prepared by combining high-sphericity high-temperature alloy powder with a plasma spraying method, the process is simple, the wall thickness of the tube is controllable, and the substrate material can be recycled.)

1. The preparation method of the nickel-based alloy thin-wall circular tube is characterized by comprising the following steps of:

step 1, weighing nickel-based alloy powder and sodium chloride, and uniformly mixing the nickel-based alloy powder and the sodium chloride according to a proportion to obtain mixed powder for later use;

step 2, weighing sodium chloride, putting the sodium chloride into a stainless steel mold, pressurizing the sodium chloride by using a pressing block, and removing the mold after the volume of the sodium chloride is unchanged to obtain a sodium chloride round bar;

step 3, spraying the mixed powder obtained in the step 1 to the surface of a sodium chloride round bar rotating at a constant speed by an atmospheric plasma spraying method;

step 4, putting the sodium chloride round bar with the coating into a vacuum furnace, sintering at high temperature, then preserving heat, and cooling to room temperature along with the furnace after heat preservation is finished;

and 5, putting the sodium chloride round bar with the coating into water, and cleaning by using ultrasonic waves until the sodium chloride round bar is dissolved and falls off to obtain the alloy round tube.

2. The method for preparing the nickel-based alloy thin-walled circular tube as claimed in claim 1, wherein in the step 1, the granularity of the alloy powder is 15-150 μm, the granularity of the sodium chloride is 20-90 μm, and the mass ratio of the sodium chloride to the alloy powder is 1: 5 to 20.

3. The method for preparing the nickel-based alloy thin-walled circular tube as claimed in claim 1, wherein in the step 2, the inner diameter of the mold is 10-100 mm, the length of the mold is 80-150 mm, and the thickness of the mold is 3 mm.

4. The method for preparing the nickel-based alloy thin-walled circular tube as claimed in claim 1, wherein in the step 3, the rotation speed of the sodium chloride round bar is 20r/min to 100r/min, and the moving speed of the plasma gun is 0.1 m/s to 2 m/s.

5. The method for preparing the nickel-based alloy thin-walled circular tube as claimed in claim 1, wherein in the step 3, the thickness of the coating is 0.2-20 mm, the length of the coating is 80-150 mm, and the diameter of the coating is 10-100 mm.

6. The method for preparing the nickel-based alloy thin-walled circular tube as claimed in claim 1, wherein in the step 4, the sintering temperature is 600-1200 ℃ and the heat preservation time is 1-3 h.

7. The method for preparing the nickel-based alloy thin-walled circular tube as claimed in claim 1, wherein in the step 5, the ultrasonic frequency is 20 to 130KHz, the cleaning time is 4 to 10 hours, and the cleaning temperature is 50 to 60 ℃.

8. The method for preparing the nickel-based alloy thin-walled circular tube as claimed in claim 1, wherein in the step 5, the inner wall and the surface of the circular tube are subjected to sand blasting.

Technical Field

The invention belongs to the technical field of high-temperature alloy powder metallurgy, and relates to a preparation method of a nickel-based alloy thin-wall circular tube.

Background

The porous material is an excellent engineering material, has double attributes of function and structure, and is a structural functional material which is widely used and has great application potential. The porous material has the characteristics of low density, high porosity, large specific surface area and the like, and is widely applied to industries such as aerospace, atomic energy, environmental protection, electrochemistry, petrochemical engineering, metallurgy, machinery, medicine, construction and the like, and occasions such as separation, filtration, gas distribution, catalysis, electrochemical processes, noise reduction, shock absorption, shielding, heat exchange and the like, and plays a great role in construction and development of scientific technology and national economy.

At present, most of common porous materials are titanium and titanium alloy or stainless steel materials. However, as the use environment is more and more severe, there is a certain development direction to prepare the porous material using the raw material having more excellent properties. The high-temperature alloy is a metal material which takes iron, nickel and cobalt as the base and can work for a long time at the high temperature of more than 600 ℃ under the action of certain stress; and has high-temperature strength, good oxidation resistance and corrosion resistance, good fatigue performance, good fracture toughness and other comprehensive properties. The porous material is prepared by taking the high-temperature alloy as a base material, and has a certain application prospect.

The traditional preparation method of the metal porous circular tube adopts a powder sintering mode, namely powder and a pore-forming agent are pressed into a specific shape and then sintered in a vacuum furnace, and for a test piece with a thin-wall appearance, the smaller the thickness of the test piece is, the greater the process difficulty is.

Disclosure of Invention

The invention aims to provide a preparation method of a nickel-based alloy thin-wall round tube, which solves the problem that the thickness of the alloy round tube is difficult to reduce in the prior art.

The technical scheme adopted by the invention is that the preparation method of the nickel-based alloy thin-wall circular tube specifically comprises the following steps:

step 1, weighing nickel-based alloy powder and sodium chloride, and uniformly mixing the nickel-based alloy powder and the sodium chloride according to a proportion to obtain mixed powder for later use;

step 2, weighing sodium chloride, putting the sodium chloride into a stainless steel mold, pressurizing the sodium chloride by using a pressing block, and removing the mold after the volume of the sodium chloride is unchanged to obtain a sodium chloride round bar;

step 3, spraying the mixed powder obtained in the step 1 to the surface of a sodium chloride round bar rotating at a constant speed by an atmospheric plasma spraying method;

step 4, putting the sodium chloride round bar with the coating into a vacuum furnace, sintering at high temperature, then preserving heat, and cooling to room temperature along with the furnace after heat preservation is finished;

and 5, putting the sodium chloride round bar with the coating into water, and cleaning by using ultrasonic waves until the sodium chloride round bar is dissolved and falls off to obtain the alloy round tube.

In the step 1, the granularity of the alloy powder is 15-150 microns, the granularity of sodium chloride is 20-90 microns, and the mass ratio of the sodium chloride to the alloy powder is 1: 5 to 20.

In the step 2, the inner diameter of the die is 10-100 mm, the length of the die is 80-150 mm, and the thickness of the die is 3 mm.

In the step 3, the rotating speed of the sodium chloride round bar is 20 r/min-100 r/min.

In the step 3, the thickness of the coating is 0.2-20 mm, the length of the coating is 80-150 mm, and the diameter of the coating is 10-100 mm.

In the step 4, the sintering temperature is 600-1200 ℃, and the heat preservation time is 1-3 h.

In the step 5, the ultrasonic frequency is 20-130 KHz, the cleaning time is 4-10 h, and the cleaning temperature is 50-60 ℃.

And 5, performing sand blasting treatment on the inner wall and the surface of the alloy round pipe.

The invention has the beneficial effects that the alloy circular tube is prepared by combining high-sphericity high-temperature alloy powder with a plasma spraying method, the process is simple, the thickness of the tube wall is controllable, and the substrate material can be recycled, so that the preparation method is economic and effective. According to the traditional preparation method, powder is pressed into a blank with a required shape, and then a final product is obtained through sintering, but as the thickness of a tube blank is reduced, the forming difficulty is increased, and a porous rod tube with the thickness smaller than 1mm is difficult to obtain, and the porous high-temperature alloy tube prepared by the method has the advantages of 0.2-20 mm in thickness, uniform pore size and certain application prospect.

Drawings

FIG. 1 is a schematic diagram of the operation of a nickel-based superalloy porous thin-walled circular tube of the present invention;

FIG. 2 is a micro-topography of a cross section of a nickel-based superalloy porous thin-walled circular tube according to the present invention.

In the figure, 1 is a plasma gun, 2 is a sodium chloride round bar, and 3 is an alloy round tube.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

The invention relates to a preparation method of a nickel-based alloy thin-wall circular tube, which comprises the following steps:

step 1, weighing nickel-based alloy powder and sodium chloride, and uniformly mixing the nickel-based alloy powder and the sodium chloride according to a proportion to obtain mixed powder for later use;

step 2, weighing sodium chloride, putting the sodium chloride into a stainless steel mold, pressurizing the sodium chloride by using a pressing block, and removing the mold after the volume of the sodium chloride is unchanged to obtain a sodium chloride round bar;

step 3, spraying the mixed powder obtained in the step 1 to the surface of a sodium chloride round bar rotating at a constant speed by an atmospheric plasma spraying method;

step 4, putting the sodium chloride round bar with the coating into a vacuum furnace, sintering at high temperature, then preserving heat, and cooling to room temperature along with the furnace after heat preservation is finished;

and 5, putting the sodium chloride round bar with the coating into water, and cleaning by using ultrasonic waves until the sodium chloride round bar is dissolved and falls off to obtain the alloy round tube.

In the step 1, the granularity of the alloy powder is 15-150 microns, the granularity of sodium chloride is 20-90 microns, and the mass ratio of the sodium chloride to the alloy powder is 1: 5 to 20.

In the step 2, the inner diameter of the die is 10-100 mm, the length of the die is 80-150 mm, and the thickness of the die is 3 mm.

In the step 3, the rotating speed of the sodium chloride round bar is 20 r/min-100 r/min.

In the step 3, the thickness of the coating is 0.2-20 mm, the length of the coating is 80-150 mm, and the diameter of the coating is 10-100 mm.

In the step 4, the sintering temperature is 600-1200 ℃, and the heat preservation time is 1-3 h.

In the step 5, the ultrasonic frequency is 20-130 KHz, the cleaning time is 4-10 h, and the cleaning temperature is 50-60 ℃.

And 5, performing sand blasting treatment on the inner wall and the surface of the alloy round pipe.

The alloy powder used in the invention is high-sphericity alloy powder prepared by a PREP technology, the thermal spraying method used in the invention is a method for heating the mixed powder to a molten or semi-molten state and striking the mixed powder to the surface of a sodium chloride round bar at a high speed to obtain a coating with a certain thickness, the method can prepare a thinner coating, and the coating thickness is easy to control.