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CN-122007431-A - Al (aluminum) alloy3Rapid preparation method of BC/Al composite powder

CN122007431ACN 122007431 ACN122007431 ACN 122007431ACN-122007431-A

Abstract

The invention belongs to the technical field of preparation of MAX phase reinforced aluminum-based composite materials, and particularly relates to a rapid preparation method of Al 3 BC/Al composite powder. The invention aims to overcome the defects of long period, high cost and difficult impurity control of the existing process. The method comprises the steps of evenly mixing raw materials through ball milling, filling the mixed powder into a carbon carrier, connecting the carbon carrier into an electrode of a joule heating device to form a loop, pumping the carbon carrier to a low vacuum degree state, charging protective gas, starting a power supply of the device, setting parameters, applying voltage to heat, and cooling to room temperature after the program operation is finished, thus obtaining the Al 3 BC/Al composite powder. The invention realizes rapid heating-cooling and simple operation by Joule heating technology, and realizes rapid preparation of composite powder, and the purity of the obtained composite powder is high. The method has the advantages of simple and convenient operation, short time consumption in the process, low cost and wide industrial application prospect.

Inventors

  • XUE WEI
  • ZHAO QIQI
  • LI TAO
  • Yang Gaochuang
  • Ji Chengshan
  • ZHANG ZHENGANG
  • WANG PEI
  • REN XUANRU
  • ZHANG YULEI

Assignees

  • 河南省科学院碳基复合材料研究院

Dates

Publication Date
20260512
Application Date
20260331

Claims (9)

  1. 1. A rapid preparation method of Al 3 BC/Al composite powder is characterized in that the rapid preparation method of Al 3 BC/Al composite powder is completed according to the following steps: 1. weighing aluminum powder, boron powder and a carbon source according to the proportion, and ball-milling and mixing uniformly; 2. Filling the mixed powder into a carbon carrier, connecting the carbon carrier with an electrode of a Joule heating device to form a loop, vacuumizing to a low vacuum, filling protective gas to a set pressure, setting target temperature, heating up rate and heat preservation time, rapidly cooling to 900-1000 ℃ and preserving heat for 30-60 s to complete a thermal cycle, repeating the cycle for 2-4 times, and cooling to room temperature to obtain the Al 3 BC/Al composite powder.
  2. 2. The rapid preparation method of the Al 3 BC/Al composite powder according to claim 1, wherein in the first step, the molar ratio of aluminum powder to boron powder to carbon source is (4-8) to 1:1.
  3. 3. The rapid preparation method of Al 3 BC/Al composite powder according to claim 1, wherein in the first step, the aluminum powder is industrial pure aluminum powder, and the average grain diameter is 1-5 μm.
  4. 4. The rapid preparation method of Al 3 BC/Al composite powder according to claim 1, wherein in the first step, the boron powder is selected from one or more of industrial boron powder, high-purity boron powder and amorphous boron powder, and the average grain size is 0.5-2 μm.
  5. 5. The method for rapidly preparing Al 3 BC/Al composite powder according to claim 1, wherein the carbon source in the first step is one or two selected from graphene and carbon nanotubes.
  6. 6. The rapid preparation method of the Al 3 BC/Al composite powder according to claim 1 is characterized in that in the first step, the ball milling speed is 150-300 r/min, the ball milling time is 2-6 h, and the ball-material ratio is 3:1-6:1.
  7. 7. The method for rapidly preparing the Al 3 BC/Al composite powder according to claim 1, wherein the shielding gas in the second step is one or two of nitrogen and argon, and the pressure of the shielding gas is 10 2 ~10 4 Pa.
  8. 8. The rapid preparation method of the Al 3 BC/Al composite powder according to claim 1, wherein the target temperature in the second step is 1000-1200 ℃, the heating rate is 50-100 ℃ per second, and the heat preservation time is 30-60 seconds.
  9. 9. The rapid preparation method of the Al 3 BC/Al composite powder according to claim 1, wherein the number of thermal cycles in the second step is 2-4, and the adjacent cycle temperature is 100-200 ℃.

Description

Rapid preparation method of Al 3 BC/Al composite powder Technical Field The invention belongs to the technical field of preparation of MAX phase reinforced aluminum matrix composite materials, and particularly relates to a rapid preparation method of Al 3 BC/Al composite powder. Background The MAX phase ceramic has the unique layered crystal structure, and has the excellent performances of high hardness and high melting point of the ceramic, heat conduction and electric conduction of metal, easy processing and the like, and becomes one of ideal candidate materials of the high-performance composite material reinforcement. The Al 3 BC is used as a typical ternary MAX phase compound, the density is only 2.83g/cm 3, the ceramic reinforcing body is far lower than that of the traditional ceramic reinforcing body, the ceramic reinforcing body has the advantage of light weight, meanwhile, the hardness is as high as 14GPa, the ceramic reinforcing body has excellent chemical stability and thermal stability, can still keep stable performance under extreme working conditions such as high temperature, corrosion and the like, and is a reinforcing phase with great potential of an aluminum-based composite material. Al 3 BC is introduced into an aluminum matrix to prepare an Al 3 BC/Al composite material, so that the strength, hardness, wear resistance and other core mechanical properties of aluminum and aluminum alloy can be obviously improved, and the composite material is widely applied to the fields with severe requirements on light weight and high performance, such as aerospace, new energy automobiles, high-end equipment manufacturing and the like. At present, the preparation core of the Al 3 BC/Al composite material is the acquisition and the compounding of an Al 3 BC reinforcement, the main flow technical route is divided into two major categories of an external reinforcement method and an in-situ autogenous method, and the two major categories are faced with significant technical bottlenecks in practical application. The preparation method of the Al 3 BC powder mainly comprises a self-propagating high-temperature synthesis method and a solid state reaction/sintering method. The self-propagating high-temperature synthesis method is characterized in that raw materials, namely aluminum particles, amorphous boron and graphite, are subjected to ball milling and then react for 3 hours at 500-1000 ℃, so that the preparation period is long, and complex impurity phases (such as Al 4C3, alN and Al 8B4C7) are formed. The solid state reaction/sintering method is to react at 500 ℃ for 24 hours and then sinter at 600 ℃ for 1 hour, and even if the synthesis of Al 3 BC powder is realized at low temperature, the preparation process is long in period and takes a long time, so that higher energy consumption is brought. In addition, longer preparations also formed more impurities, such as AlB 2、γ-Al2O3 and MgAl 2 O. The three-stage sintering method is adopted in the report of CN116730723A, namely an Al 3 BC ceramic material, a preparation method and application thereof, and the three-stage sintering method is adopted for sintering at 550-650 ℃ for 1-2 hours, 700-800 ℃ for 2-5 hours and 900-1000 ℃ for 1-3 hours respectively. The method still maintains a certain proportion of raw materials Al and B 4 C powder impurities while obtaining Al 3 BC powder, and needs long-time sintering to ensure sufficient reaction, and the application of the method is limited by the longer period and high cost requirement in the preparation process. in addition, the purity of the product is reduced due to the introduction of impurities, and a subsequent purification process is required, which also increases the preparation period and cost. In-situ synthesis of Al 3 BC/Al composite material is usually realized through liquid-solid reaction, the reaction process is more difficult to control, brittle impurity phases such as Al 4C3、AlB2, al 8B4C7 and the like are easy to generate, and the mechanical property is seriously reduced. CN115921849A reports a spherical Al 3 BC/Al composite powder and a preparation method thereof, namely, the Al 3 BC/Al composite powder is synthesized by adopting a spray granulation combined with a low-temperature and high-temperature calcination method, and the preparation method has the advantages of more operation steps and long preparation period (about 3-36 h). The existing preparation process of the Al 3 BC/Al composite powder has common defects of long preparation period, high production cost and difficult control of impurity phases, and the existing process is difficult to consider the phase purity, production efficiency and cost control, so that the large-scale application requirements of the Al 3 BC/Al composite material in high-end fields such as aerospace, new energy and the like can not be met. Therefore, developing a rapid and efficient preparation method of Al 3 BC/Al composite powder with low impurity content a