CN-116377587-B - Preparation method of aluminum alloy dendrite

Abstract

The invention provides a preparation method of aluminum alloy dendrites, which is characterized in that dendrites prepared by the preparation method are more single, dendrites are not interfered with each other, the formed dendrites are more independent, compared with dendrites obtained by other methods, the dendrites obtained by the method are more complete, the growth mode is more free, the dendrites can not mutually compete for growth due to the change of a cooling mode and a cooling gradient direction, the defects of grain boundaries and the like can not be generated, and only single dendrites grow downwards in a straight dendrite mode, so that the preparation method is hopeful to obtain complete single dendrites of aluminum alloy dendrites, further research whether dendrite element segregation exists in dendrites or not, and the minimum composition unit of dendrites, and further provide theoretical support for researching secondary units of aluminum alloy dendrites. The invention avoids the limit of the traditional alloy material production process, produces complete single aluminum alloy dendrites, and provides feasibility support for the research of the aluminum alloy dendrites.

Inventors

• ZHUANG DAYONG
• REN DAWEI
• LI YANG
• ZHANG JIAN
• XIAO TAO
• GUO TIANZHI
• GAO FENG

Assignees

• 中船重工龙江广瀚燃气轮机有限公司

Dates

Publication Date

20260508

Application Date

20230220

Claims (1)

1. 1. The preparation method of the aluminum alloy dendrite is characterized by comprising the following steps of: Step 1, weighing 170g of raw materials, wherein the chemical components of the raw materials are Al-8.90Si-0.64P-0.57Pd-0.28Fe-0.24Ag-0.16Cd-0.10Mo-0.06Zn-0.05Ni-0.04Nb, putting the raw materials into a beaker, removing surface impurities and oil stains by using acetone, putting the raw materials into the beaker for 5min, pouring out the acetone, flushing by using deionized water to prevent the introduction of impurities and trace elements and influence the preparation of final dendrites, putting the raw materials into the beaker again, adding an alcohol solution, putting the raw materials into an ultrasonic cleaner, washing the raw materials for 15min, pouring the raw materials into filter paper, waiting for natural drying, continuously weighing the dried raw materials, and taking out 150g of raw materials for experiments; Step 2, before the experiment starts, checking whether a heating device can be normally used, checking whether an air path and a water path are normal, wherein the heating device is required to have an error range of +/-3 ℃ within a temperature range of 900-1000 ℃, the temperature rising rate is 5 ℃ per minute, the pressure of cooling water is 0.03-0.05 MPa, the temperature of the cooling water is 5-25 ℃, the pressure of gas is 0.05MPa, whether a graphite crucible is damaged or not, whether holes and cracks exist in an inner crucible or not, and filling raw materials to keep melted liquid of raw materials from overflowing the inner crucible and being polluted by an outer crucible; Step 3, when the experiment starts, ensuring that Ar is introduced with exhaust air, circularly exhausting the air for a plurality of times, introducing H 2 to heat aluminum particles in a crucible, controlling the temperature to be 200-300 ℃, keeping the temperature for 30min, then raising the temperature of a high-temperature furnace, when the temperature of the high-temperature furnace reaches the temperature, introducing HCl gas, controlling the temperature of the high-temperature furnace to be 900-1000 ℃, keeping the temperature for 3H, then closing a heating device, closing the introduction of H 2 and the HCl gas, continuously and slowly introducing Ar gas, and slowly cooling to room temperature; step 4, the prepared dendrite is clamped by tweezers, when the dendrite is extracted for Scanning Electron Microscope (SEM) detection, the surface of the dendrite is required to be cleaned before detection, then the dendrite is naturally dried, the obtained dendrite is put into a digital microscope (OM) of the Scanning Electron Microscope (SEM) for detection, and due to the characteristics of small volume and easy bending, a conductive adhesive tape is adopted for sticking during detection; And (3) introducing Ar gas to circularly remove air, and controlling the pressure of H 2 and the pressure of HCl gas to be 0.1MPa and 0.05MPa respectively.

Description

Preparation method of aluminum alloy dendrite Technical Field The invention belongs to the technical field of materials, and particularly relates to a preparation method of aluminum alloy dendrites. Background In recent years, with the development of technology, parts produced by the conventional solidification technology cannot meet the use requirements under severe service conditions, and new manufacturing technologies are urgently needed to produce parts with higher performance, particularly parts for gas turbines and aeroengines, which are required to bear centrifugal forces at high temperatures of at least more than 1000 ℃ and 10000rpm, which cannot be born for a long time by parts produced by the conventional solidification technology, and the limiting performance of materials must be improved. In order to improve the current situation, the directional solidification technology and the single crystal blade preparation technology of the invention are urgent, but the existing directional solidification and single crystal technology has many defects, and the problems of impossible mass production, low yield, too small parts and the like exist, which are mainly caused by the theoretical insufficient cognition of the dendrite growth mechanism on a microscopic scale. For this reason, numerous scientists and scholars want to thoroughly research and understand the growth mechanism of dendrites, all hope to prepare ideal dendrite structures by various methods including laser chilling technology, electron beam melting pool solidification technology, directional solidification technology, single crystal technology and surface grinding technology, but all the methods can not produce dendrites of single dendrite structures, many kinds of dendrite assemblies can not convert the dendrite structures of microscopic dimensions to macroscopic dimensions, more can not research and detect the growth rule of single dendrites, more research is built on dendrite simulation and theoretical model, and few research is done on preparing single dendrites. Al-Si alloys have been studied earlier as dendrite materials, and some documents have shown that some theoretical studies and theoretical models are used to detect the influence of solidification parameters on microstructure characterization, mainly including primary dendrite spacing, secondary dendrite spacing, radius of dendrite tips, temperature gradient, dendrite growth rate, and the like, and some documents have studied the influence of solidification process parameters and Si element content on dendrite spacing and hardness, but have not been found in the literature technology for preparing Al-Si alloy dendrites by vapor phase solidification technology. Disclosure of Invention The invention aims to provide a preparation method for preparing aluminum alloy dendrites, which reveals the growth rule and morphology of the aluminum alloy dendrites and researches the morphology characteristics of the aluminum alloy dendrites from a macroscopic scale. . The preparation method of the aluminum alloy dendrite comprises the following steps: Step 1, weighing 170g of raw materials, wherein the chemical components of the raw materials are Al-8.90Si-0.64P-0.57Pd-0.28Fe-0.24Ag-0.16Cd-0.10Mo-0.06Zn-0.05Ni-0.04Nb, putting the raw materials into a beaker, removing surface impurities and oil stains by using acetone, putting the raw materials into the beaker for 5min, pouring out the acetone, flushing by using deionized water to prevent the introduction of impurities and trace elements and affecting the preparation of final dendrites, putting the raw materials into the beaker again, adding an alcohol solution, putting the raw materials into an ultrasonic cleaner, washing the raw materials for 15min, pouring the raw materials into filter paper, waiting for natural drying, continuously weighing the dried raw materials, and taking out 150g of raw materials for experiments. And 2, before the experiment starts, checking whether the heating device can be normally used, checking whether the air path and the water path are normal, wherein the error range of the heating device is +/-3 ℃ within the range of 900-1000 ℃, the temperature rising rate is 5 ℃ per minute, the water pressure of cooling water is 0.03-0.05 MPa, the temperature of the cooling water is 5-25 ℃, the gas pressure is 0.05MPa, whether a graphite dry pot is damaged or not, whether holes and cracks exist in the inner dry pot or not, and filling raw materials to keep the melted liquid of the raw materials from overflowing the inner dry pot as far as possible and being polluted by the outer dry pot. And 3, when the test starts, ensuring that Ar is introduced into the crucible to discharge air, circularly discharging the air for a plurality of times, introducing H 2 to heat aluminum particles in the crucible, controlling the temperature to be 200-300 ℃, keeping the temperature for 30min, then raising the temperature of a high-temperature furn