Preparation method of stainless steel fiber reinforced magnesium-based composite material

Abstract

The invention discloses a preparation method of a stainless steel fiber reinforced magnesium-based composite material, and belongs to the technical field of magnesium-based composite material preparation. The method comprises the following steps: firstly, plating a layer of copper film on stainless steel fibers by adopting a vacuum evaporation method, then smelting a magnesium alloy in an argon protection environment, after the magnesium alloy is smelted, cooling to a semi-solid state, stirring by using a stirrer, adding copper-plated stainless steel fibers, finally heating to a casting temperature, and casting to obtain a magnesium-based composite material cast ingot. According to the method, the stainless steel fibers are introduced into the magnesium alloy at low cost, the mechanical property of the magnesium alloy can be well improved, operation is easy, and the method is suitable for large-scale production.

Description

Technical Field

[0001] This invention relates to a method for preparing stainless steel fiber reinforced magnesium-based composite material, belonging to the field of magnesium-based composite material preparation technology. Technical Background

[0002] Magnesium alloys possess advantages such as high specific strength, high specific stiffness, and low density, making them promising for applications in aerospace, automotive, and other fields. However, their low strength and poor wear resistance limit their further promotion. Composite methods can effectively enhance the strength and ductility of magnesium alloys.

[0003] The preparation methods and processes of fiber-reinforced magnesium matrix composites have a significant impact on the material's properties, and its cost also depends on the manufacturing technology. Due to the high surface tension of magnesium alloy melts and the poor wettability between stainless steel fibers and the melt, efficient introduction is difficult. Currently, most methods for preparing magnesium alloy fiber composites involve preparing a fiber preform and then using pressureless or pressurized infiltration to impregnate the magnesium alloy melt into the preform. However, this method is greatly affected by the size and morphology of the preform, making mass production impossible.

[0004] Invention patent CN202111135526.7, "A Preparation Method of Fiber-Reinforced Aluminum Matrix Composite Material," relates to an impregnation preparation method for fiber-reinforced aluminum matrix composite materials. Its characteristic is that after completely impregnating the aluminum matrix material into a porous preform composed of fibers, air bubbles in the alloy are removed, and the composite material is obtained after cooling. This invention is beneficial for improving the bonding degree between the fibers and the aluminum matrix and is suitable for small-batch production. However, due to its complex operation and high cost, large-scale production application is difficult. Vamsee Pamula et al. studied the preparation of aluminum matrix composite materials by continuously embedding stainless steel fibers into a mold. This method is simple and easy to operate, but because the stainless steel fibers are continuously embedded into the mold, uneven dispersion may occur, and it is not suitable for the preparation of complex workpieces. Xie Liwen et al. studied the preparation of magnesium-based biomimetic composite materials using commercial 316L stainless steel mesh as the reinforcing material and a pressureless melt infiltration method. At room temperature and 200℃, the yield strength, tensile strength, and work hardening rate of the stainless steel fiber-reinforced magnesium matrix composite material were significantly improved. However, due to the large amount of stainless steel fiber mesh added, the density of the magnesium alloy increases, which is not conducive to the preparation of complex components and large-scale production. Summary of the Invention

[0005] The main objective of this invention is to overcome the shortcomings of the prior art and provide a new method for preparing fiber-reinforced magnesium-based composite materials.

[0006] This invention is achieved through the following technical solution: a method for preparing stainless steel fiber reinforced magnesium matrix composite material, comprising the following steps:

[0007] 1. A method for preparing a stainless steel fiber reinforced magnesium matrix composite material, characterized in that the step of preparing vacuum-deposited copper stainless steel fibers includes:

[0008] Step 1: Place stainless steel fibers with a diameter of 10-20μm into acetone, alcohol, and deionized water in sequence and clean them with ultrasound for 10 minutes each. Then, dry them in a drying oven at 100℃ and then place them in a multi-functional high-vacuum thermal evaporation coating machine for vacuum evaporation coating of copper film.

[0009] Step 2: Wrap pure copper wire around the two heating elements, evacuate the vacuum, and heat to approximately 1000°C using inductive heating. The fractionated Cu atoms are deposited on the stainless steel fibers to form a copper film.

[0010] Step 3: After removing the copper-plated stainless steel fiber, place it in a vacuum annealing furnace at 200-250℃ for annealing treatment for 1-1.5 hours. The final diameter of the copper-plated stainless steel fiber is 15-25μm.

[0011] 2. A method for preparing a stainless steel fiber reinforced magnesium matrix composite material, characterized in that the steps for preparing the stainless steel fiber reinforced magnesium matrix composite material include:

[0012] Step 1: The amount of copper-plated stainless steel fiber added is 0.5-3.0 wt.%. Weigh a certain mass of magnesium alloy and copper-plated stainless steel fiber, and bake the copper-plated stainless steel fiber in a temperature range of 300-350℃.

[0013] Step 2: Place the magnesium alloy in a crucible, introduce argon gas, and heat it to 680-700℃ under argon protection to melt it.

[0014] Step 4: After the magnesium alloy melts, use a slag skimmer to remove the slag from the melt and continuously purge with argon gas for protection. Step 5: Cool the magnesium alloy melt to 650-660℃, then stir the magnesium alloy melt with a stirrer at 900-1000 rpm, and evenly sprinkle the preheated copper-plated stainless steel fibers into the melt.

[0015] Step 6: After all the copper-plated stainless steel fibers are mixed into the melt, reduce the stirring speed to 200-300 r / min, and heat the melt to a casting temperature of 680-700℃. Then pour it into a preheated mold to obtain a stainless steel fiber reinforced magnesium matrix composite ingot.

[0016] Compared with the prior art, the present invention has the advantages of: short operation process, no need for complex equipment, simple addition method, low production cost, and suitability for large-scale production. Attached Figure Description

[0017] Figure 1 This is a process flow diagram of the present invention.

[0018] Figure 2 SEM image of Example 1

[0019] Figure 3 Stress-strain curves of examples 1, 2, and 3 Detailed Implementation

[0020] To make the technical problems, technical solutions, and advantages of the present invention clearer, the present invention will be further described below in conjunction with the embodiments, but the present invention is not limited to the listed embodiments.

[0021] Example 1

[0022] 1. Preparation of vacuum-deposited copper stainless steel fibers, including the following steps:

[0023] Step 1: Place the 20μm diameter stainless steel fiber into acetone, alcohol and deionized water in sequence and clean it with ultrasound for 10 minutes each. Then place it in a drying oven at 100℃ to dry, and then place it in a multi-functional high vacuum thermal evaporation coating machine to vacuum deposit copper film.

[0024] Step 2: Wrap pure copper wire around two heaters respectively, evacuate the vacuum, and heat to 1000℃ via inductive heating. The fractionated Cu atoms are deposited on the stainless steel fibers to form a copper film.

[0025] Step 3: After removing the copper-plated stainless steel fiber, place it in a 200℃ vacuum annealing furnace for 1 hour of annealing treatment. The final diameter of the copper-plated stainless steel fiber is 25μm.

[0026] 2. Preparation of stainless steel fiber reinforced magnesium matrix composite material, the steps include:

[0027] Step 1: The amount of copper-plated stainless steel fiber added is 1.0 wt.%. Weigh 990g of ZM5 and 10g of copper-plated stainless steel fiber, and preheat the copper-plated stainless steel fiber at 300℃.

[0028] Step 2: Place the magnesium alloy in a crucible, introduce argon gas, and heat it to 700°C under argon protection to melt it.

[0029] Step 3: After the magnesium alloy melts, use a slag skimmer to remove the slag from the melt and continuously purge with argon gas for protection. Step 4: Cool the magnesium alloy melt to 660℃, then stir the magnesium alloy melt with a stirrer at 1000 rpm, and evenly sprinkle the preheated copper-plated stainless steel fibers into the melt.

[0030] Step 5: After all the copper-plated stainless steel fibers are mixed into the melt, reduce the stirring speed to 200 r / min and heat the melt to a casting temperature of 680℃. Then pour it into a preheated mold to obtain a stainless steel fiber reinforced magnesium matrix composite ingot.

[0031] Example 2

[0032] 1. Preparation of vacuum-deposited copper stainless steel fibers, including the following steps:

[0033] Step 1: Place the 20μm diameter stainless steel fiber into acetone, alcohol and deionized water in sequence and clean it with ultrasound for 10 minutes each. Then place it in a drying oven at 100℃ to dry, and then place it in a multi-functional high vacuum thermal evaporation coating machine to vacuum deposit copper film.

[0034] Step 2: Wrap pure copper wire around two heaters respectively, evacuate the vacuum, and heat to 1000℃ via inductive heating. The fractionated Cu atoms are deposited on the stainless steel fibers to form a copper film.

[0035] Step 3: After removing the copper-plated stainless steel fiber, place it in a 200℃ vacuum annealing furnace for 1 hour of annealing treatment. The final diameter of the copper-plated stainless steel fiber is 25μm.

[0036] 2. Preparation of stainless steel fiber reinforced magnesium matrix composite material, the steps include:

[0037] Step 1: The amount of copper-plated stainless steel fiber added is 0.5wt.%. Weigh 995g of ZM5 and 5g of copper-plated stainless steel fiber, and preheat the copper-plated stainless steel fiber at 300℃.

[0038] Step 2: Place the magnesium alloy in a crucible, introduce argon gas, and heat it to 700°C under argon protection to melt it.

[0039] Step 3: After the magnesium alloy melts, use a slag skimmer to remove the slag from the melt and continuously purge with argon gas for protection. Step 4: Cool the magnesium alloy melt to 660℃, then stir the magnesium alloy melt with a stirrer at 1000 rpm, and evenly sprinkle the preheated copper-plated stainless steel fibers into the melt.

[0040] Step 5: After all the copper-plated stainless steel fibers are mixed into the melt, reduce the stirring speed to 200 r / min and heat the melt to a casting temperature of 680℃. Then pour it into a preheated mold to obtain a stainless steel fiber reinforced magnesium matrix composite ingot.

[0041] Example 3

[0042] The steps for preparing the ZM5 comparative sample include:

[0043] Step 1: Weigh 900g of ZM5, place it in a crucible, introduce argon gas, and heat it to 700℃ under argon protection to melt it.

[0044] Step 2: After the magnesium alloy melts, use a slag skimmer to remove the slag from the melt and continue to introduce argon gas. Step 3: Cool the magnesium alloy melt to 660℃, and then stir the magnesium alloy melt with a stirrer at 1000 r / min.

[0045] Step 4: Reduce the stirring rate to 200 r / min and heat the melt to 680℃ for casting. Then pour it into a preheated mold to obtain ZM5 ingots.

[0046] Table 1 Mechanical properties of Examples 1-3

[0047]

Claims

1. A method for preparing a stainless steel fiber reinforced magnesium matrix composite material, characterized in that, The steps for preparing vacuum-deposited copper stainless steel fibers include: Step 1: Place stainless steel fibers with a diameter of 10-20μm into acetone, alcohol, and deionized water in sequence and clean them with ultrasound for 10 minutes each. Then, dry them in a drying oven at 100℃ and then place them in a multi-functional high-vacuum thermal evaporation coating machine for vacuum evaporation copper film deposition. Step 2: Wrap pure copper wire around the two heating elements respectively, evacuate the vacuum, and inductively heat to 1000℃, so that the fractionated Cu atoms are deposited on the stainless steel fiber to form a copper film. Step 3: After removing the copper-plated stainless steel fiber, place it in a vacuum annealing furnace at 200-250℃ for annealing treatment for 1-1.5 hours. The final diameter of the copper-plated stainless steel fiber is 15-25μm.

2. A method for preparing a stainless steel fiber reinforced magnesium matrix composite material, characterized in that, The steps for preparing stainless steel fiber reinforced magnesium matrix composites include: Step 1: The amount of copper-plated stainless steel fiber added is 0.5-3.0 wt.%. Weigh a certain mass of magnesium alloy and copper-plated stainless steel fiber, and bake the copper-plated stainless steel fiber in a temperature range of 300-350℃. Step 2: Place the magnesium alloy in a crucible, introduce argon gas, and heat it to 680-700℃ under argon protection to melt it. Step 3: After the magnesium alloy melts, use a slag skimmer to remove the slag from the melt and continuously introduce argon gas for protection. Step 4: Cool the magnesium alloy melt to 650-660℃, then stir the magnesium alloy melt with a stirrer at 900-1000r / min, and evenly sprinkle the preheated copper-plated stainless steel fibers into the melt. Step 5: After all the copper-plated stainless steel fibers are mixed into the melt, reduce the stirring speed to 200-300 r / min, and heat the melt to a casting temperature of 680-700℃. Then pour it into a preheated mold to obtain a stainless steel fiber reinforced magnesium matrix composite ingot.

Images