阅读说明：本技术 一种亚稳态硅黄铜颗粒气水耦合制备方法 (Gas-water coupling preparation method of metastable silicon brass particles ) 是由 钟素娟 龙伟民 于奇 马佳 于新泉 潘建军 纠永涛 于 2019-10-18 设计创作，主要内容包括：本发明提供了一种亚稳态硅黄铜颗粒气水耦合制备方法,将高温合金液流体分别通过在低压气、水耦合碰撞打散,最终制备表面状态好、球形度高、粒径分布集中、成分无偏析及氧化物夹杂的硅黄铜颗粒,制备过程中高温合金液流体首先采用低压气雾化法打散,雾化所用气喷嘴采用开放式设计,采用低压氮气作为雾化介质,气喷嘴与垂直中轴线夹角设计为30~60°,气压调整为0.5~1MPa,喷嘴上方0~30mm保证微负压,气压交点在喷嘴下方30~50mm；二次打散采用低压联排水雾化法,低压联排水所用水喷嘴的出口位置设置在气压紊流区,水压力调整为5~10MPa。本发明制备的硅黄铜颗粒表面状态好,且组织无成分偏析及氧化物夹杂。(The invention provides a metastable silicon brass particle gas-water coupling preparation method, which comprises the steps of scattering high-temperature alloy liquid fluid by coupling and collision of low-pressure gas and water respectively, and finally preparing silicon brass particles with good surface state, high sphericity, concentrated particle size distribution, and no segregation and oxide inclusion in components, wherein the high-temperature alloy liquid fluid is scattered by a low-pressure gas atomization method firstly in the preparation process, a gas nozzle used for atomization adopts an open design, low-pressure nitrogen is adopted as an atomization medium, an included angle between the gas nozzle and a vertical central axis is designed to be 30 ~ 60 degrees, the gas pressure is adjusted to be 0.5 ~ 1MPa, the micro negative pressure is ensured at 0 ~ 30mm above the nozzle, a gas pressure intersection point is 30 ~ 50mm below the nozzle, the secondary scattering adopts a low-pressure drainage water atomization method, the outlet position of the water nozzle used for low-pressure drainage is arranged in a gas pressure turbulent flow zone, and the water pressure is adjusted to be 5 ~ 10 MPa.)

1. A metastable state silicon brass particle gas-water coupling preparation method is characterized in that: the method comprises the following specific steps:

injecting molten silicon brass high-temperature melt into a crucible with a through hole at the bottom for bottom leakage casting, wherein the through hole of the crucible is also connected with a flow guide pipe;

secondly, after the silicon brass high-temperature melt flows out of the crucible, primary scattering is carried out through an air nozzle arranged below a flow guide pipe, the atomizing medium for primary scattering is nitrogen, and the nitrogen pressure is 0.5 ~ 1MPa, so that the primary scattered silicon brass high-temperature molten drops are obtained;

thirdly, low-pressure linkage drainage is arranged below the gas nozzle, high-temperature molten drops of the silicon brass are scattered for the first time, secondary scattering and cooling are carried out at the low-pressure linkage drainage, the water pressure of water sprayed by the low-pressure linkage drainage is 5 ~ 10MPa, and metastable-state silicon brass particles are obtained after secondary scattering and cooling;

and step four, collecting the metastable silicon brass particles subjected to secondary scattering and cooling to finish the preparation.

2. The gas-water coupling preparation method of the metastable silicon brass particles according to claim 1, characterized in that: and in the fourth step, the waste water is collected by a material collecting bin arranged below the low-pressure joint drainage.

3. The gas-water coupling preparation method of the metastable silicon brass particles according to claim 2, characterized in that: the material collecting bin is a cylindrical shell with an opening at the top, and further comprises a cylindrical bin shell and a material collecting groove with a sealed bottom surface, and the material collecting groove is further connected to the lower end face of the bin shell through a conical shell.

4. The gas-water coupling preparation method of the metastable silicon brass particles according to claim 3, characterized in that: the air nozzle and the low-pressure joint drainage are both arranged in the bin shell.

5. The gas-water coupling preparation method of the metastable silicon brass particles as claimed in claim 1 or 4, wherein the included angle between the gas nozzle and the vertical central axis is 30 ~ 60 degrees, the negative pressure is 0 ~ 30mm above the gas nozzle, and the gas pressure intersection point sprayed by the gas nozzle is 30 ~ 50mm below the gas nozzle.

6. The gas-water coupling preparation method of the metastable silicon brass particles according to claim 1 or 4, characterized in that: the low-pressure water drainage system comprises a plurality of water nozzles, and the low-pressure water drainage system is arranged in an air pressure turbulent flow area of air flow sprayed by the air nozzles.

Technical Field

The invention belongs to the technical field of alloys, and particularly relates to a gas-water coupling preparation method of metastable silicon brass particles.

Background

Brass has excellent mechanical properties, is one of the most widely used alloy materials in nonferrous metals, and is widely applied to the fields of electronic telecommunication, household appliances, drinking water engineering, aerospace, hardware decoration, machinery, instruments and the like. Simple brass consists of copper-zinc binary alloy components, other elements are added into the brass to form complex brass, and silicon element is an important alloy element in the complex brass. The silicon brass can obviously improve the wear resistance and corrosion resistance of the brass alloy, when the silicon content is too high, the plasticity of the alloy material is severely reduced, and the pressure processing is difficult to carry out, and the alloy particles prepared by material forming can shorten the material processing flow, avoid the pressure processing and meet the material requirements of casting and welding. In the process of forming silicon brass particles, due to the fact that solute is discharged in the process of material shrinkage and solidification, the structure shrinkage is inconsistent, the defects of looseness and the like occur inside, and the use performance of alloy particles is affected.

Disclosure of Invention

In order to solve the problems, the invention provides a gas-water coupling preparation method of metastable silicon brass particles, and the prepared silicon brass particles have the advantages of good surface state, high sphericity, concentrated particle size distribution and no composition segregation and oxide inclusion in the structure.

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

a metastable state silicon brass particle gas-water coupling preparation method is characterized in that: the method comprises the following specific steps:

injecting molten silicon brass high-temperature melt into a crucible with a through hole at the bottom for bottom leakage casting, wherein the through hole of the crucible is also connected with a flow guide pipe;

secondly, after the silicon brass high-temperature melt flows out of the crucible, primary scattering is carried out through an air nozzle arranged below a flow guide pipe, the atomizing medium for primary scattering is nitrogen, and the nitrogen pressure is 0.5 ~ 1MPa, so that the primary scattered silicon brass high-temperature molten drops are obtained;

thirdly, low-pressure linkage drainage is arranged below the gas nozzle, high-temperature molten drops of the silicon brass are scattered for the first time, secondary scattering and cooling are carried out at the low-pressure linkage drainage, the water pressure of water sprayed by the low-pressure linkage drainage is 5 ~ 10MPa, and metastable-state silicon brass particles are obtained after secondary scattering and cooling;

and step four, collecting the metastable silicon brass particles subjected to secondary scattering and cooling to finish the preparation.

Furthermore, in the fourth step, the waste water is collected by a collecting bin arranged below the low-pressure drainage.

Furthermore, the material collecting bin is a cylindrical shell with an opening at the top, and further comprises a cylindrical bin shell and a material collecting groove with a sealed bottom surface, and the material collecting groove is connected to the lower end surface of the bin shell through a conical shell.

Further, the air nozzle and the low-pressure joint drainage are arranged inside the bin shell.

Furthermore, the included angle between the air nozzle and the vertical central axis is 30 ~ 60 degrees, negative pressure is arranged 0 ~ 30mm above the air nozzle, and the intersection point of the air pressure sprayed out by the air nozzle is 30 ~ 50mm below the air nozzle.

Further, the low-pressure water drainage system comprises a plurality of water nozzles, and the low-pressure water drainage system is arranged in an air pressure turbulent flow area of air flow sprayed by the air nozzles.

The invention has the beneficial effects that: the air-water coupling preparation method of the metastable silicon brass particles is used for preparing silicon brass materials difficult to be processed under pressure, and the nearly spherical brass particles which are quickly condensed and shrunk and have concentrated particle size distribution are prepared under the action of low-pressure air-water coupling scattering; the silicon brass particles prepared by the method have the advantages of good surface state, high sphericity, concentrated particle size distribution, high cooling speed of alloy melt in the preparation process, and no component segregation and oxide inclusion in the structure.

Drawings

FIG. 1 is a schematic diagram of a gas-water coupling preparation method of metastable silicon brass particles according to the invention;

FIG. 2 is a schematic view of a low pressure water jet tangential nozzle;

FIG. 3 is a particle morphology map of example 1;

FIG. 4 is a view of the internal microstructure of example 1;

FIG. 5 is a particle morphology map of example 2;

FIG. 6 is a view of the internal microstructure of example 2;

FIG. 7 is a particle morphology map of example 3;

FIG. 8 is a view of the internal microstructure of example 3.

The reference numbers include: 1. a crucible; 2. silicon brass high-temperature molten fluid; 3. a flow guide pipe; 4. an air nozzle; 5. a water nozzle; 6. a material collecting bin; 601. a bin shell; 602. a material collecting groove.

Detailed Description

In order that those skilled in the art will be able to better understand the technical solutions provided by the present invention, the following description is provided in connection with specific embodiments.

A metastable silicon brass particle gas-water coupling preparation method is characterized in that high-temperature alloy liquid fluid 2 is scattered through coupling collision under low pressure gas and water respectively, and finally silicon brass particles which are good in surface state, high in sphericity, concentrated in particle size distribution, free of segregation and oxide inclusion in components are prepared.

The high-temperature alloy liquid fluid 2 is firstly scattered by adopting a low-pressure gas atomization method, a gas nozzle 4 used for atomization adopts an open design, low-pressure nitrogen is adopted as an atomization medium, an included angle between the gas nozzle 4 and a vertical central axis is designed to be 30 ~ 60 degrees, the air pressure is adjusted to be 0.5 ~ 1MPa, the micro negative pressure is ensured at 0 ~ 30mm above the nozzle, the intersection point of the air pressure is 30 ~ 50mm below the nozzle, the secondary scattering adopts a low-pressure joint drainage atomization method, the outlet position of a water nozzle 5 used for low-pressure joint drainage is arranged in an air pressure turbulent flow region, and the water pressure is adjusted to be 5 ~ 10 MPa.