How to prepare aluminum carbide

Aluminum is the most abundant metallic element in the earth's crust. It is widely used in industry because of its light weight and good formability. However, aluminum and its alloys face development problems such as low strength, wear resistance, and poor high temperature performance. Aluminum carbide (Al4C3) is an ionic compound with a diamond-hexahedral structure, with high hardness, shear strength and melting point, and is an ideal second-phase strengthening material for aluminum-based materials.

Aluminum carbide gold hexagonal flake crystals. The relative density is 2.36, stable at 1400℃, and decomposed above 2200℃.

What happens when aluminum carbide reacts with water? Aluminum carbide (Al4C3) reacts with water to form methane (CH4). The chemical reaction can be written as Al4 C3 +12H2 O→4Al(OH)3 +3CH4 . In case of water, it decomposes to form methane, which is stored in a dry and cool place, insoluble in acetone, and decomposed by dilute acid. It is made by heating pure aluminium powder with pure carbon. At present, the preparation methods of aluminum carbide mainly include metal direct carbonization method, carbothermal reduction method, sol-gel method, microwave synthesis method, high-energy mechanical ball milling method, etc.

How to prepare aluminum carbide

Direct metal carbonization and carbothermal reduction are the earliest synthetic methods, and some technologies have been applied to industrial production. However, the disadvantages of these two methods are high synthesis temperature, long reaction time and large particle size. However, in the known high-energy ball milling methods, the focus is mainly on the in-situ synthesis of small amounts of Al4C3 to enhance the Al-based material, rather than the high-purity synthesis of Al4C3. At the same time, the high-energy ball mill itself also has shortcomings such as long ball milling time, high energy consumption, and uneven powder particles.

A method for preparing aluminum carbide powder by plasma ball milling, comprising the following steps:

(1) Mix the aluminum powder and the graphite powder simply and uniformly, and grind (refine and activate) the mixed powder with a plasma ball mill under the protection of argon gas; the mass ratio of the graphite powder in the mixed powder is 35%, and the residue is aluminum Powder; Ball Milling Conditions: Rotational speed 960rpm, discharge current 1.5a, ball-to-material ratio 50:1, ball milling time 1h (excluding downtime). The running mode is 30 minutes and 30 minutes to restart alternately (30 minutes for ball milling, 30 minutes for stopping ball milling, 30 minutes for ball milling, and so on);

 (2) After mixing the powder in the ball mill, cover the alumina crucible, put the pot into the vacuum tube furnace, use the vacuum pump to 10pa in the vacuum furnace tube, pass argon gas, keep the argon gas circulating, and repeat in the tube furnace (flow rate 100 ml/min), rise to 1000 °C at a heating rate of 10 °C/min and hold for 4 h, then air-cooled tube furnace (cooled to room temperature within 100 min), at the end of aluminum carbide.

Overview of aluminum carbide Al4C3 powder

Aluminum carbide Al4C3 powder is an inorganic compound with the molecular formula Al4C3. Yellow or green-gray crystal block or powder, hygroscopic. Decomposes at high temperature and decomposes into methane and aluminum hydroxide in cold water. Al4C3 has a hexagonal crystal structure. Aluminum carbide chemical formula Al4C3 is a carbide of aluminum. Appearance is pale yellow to brown crystals. Stable at temperatures up to 1400°C. Decomposes in water to form methane.

Aluminum carbide Al4C3 powder has an unusual crystal structure consisting of alternating layers of Al2C and Al2C2. Each aluminum atom is matched with 4 carbon atoms to form a tetrahedral arrangement. Carbon atoms exist in two different binding environments. One is a deformed octahedron with 6 Al atoms at 217 pm. The other is a twisted triangular bipyramid structure with 4 Al atoms at 190-194 pm and a fifth Al atom at 221 pm.

A small amount of aluminum carbide is a common impurity in industrial calcium carbide. In the electrolytic manufacture of aluminium, aluminium carbide is a corrosion product of graphite electrodes.

In metal matrix composites based on non-metallic carbides (silicon carbide, boron carbide, etc.) or carbon fiber reinforced aluminum matrix, aluminum carbide is often a poor quality product. For carbon fibers, it reacts with the aluminum matrix at temperatures above 500°C; for example, better fiber wettability and chemical reaction inhibition can be obtained by coating the fibers with calcium carbonate. Large quantities of aluminum carbide are usually immediately available. Carbides are compounds with an anion of one or more carbon atoms. Most metals, though not all, form carbides: indium and gallium, for example, do not. Like diamonds (pure carbon substances), carbides tend to be very hard, fire-resistant, wear-resistant, corrosion-resistant, and heat-resistant, making them ideal for use as a coating for drill bits and other tools. They often combine toughness with other valuable properties such as electrical conductivity, low thermal expansion and wear resistance.

Aluminum carbide Al4C3 powder is produced by the direct reaction of aluminum and carbon in an electric arc furnace.

4 Al+3 C→ Al4C3

Other reactions start with alumina, but they are not very favorable due to the production of carbon monoxide.

2 Al2O3+9 C→ Al4C3 +6 CO

Silicon carbide also reacts with aluminum to form Al4C3. This transformation limits the mechanical application of SiC because Al4C3 is more brittle than SiC.

4 Al+3 SiC→Al4C3+3 Si

In silicon carbide reinforced aluminum matrix composites, silicon carbide reacts chemically with molten aluminum to form a layer of aluminum carbide on the silicon carbide particles, reducing the strength of the material but increasing the wettability of the silicon carbide particles. This tendency can be reduced by coating the silicon carbide particles with a suitable oxide or nitride, pre-oxidizing the particles to form a silica coating, or using a sacrificial metal layer.

Aluminum aluminum carbide composites can be made by mechanical alloying and mixing aluminum powder with graphite particles.

Aluminum carbide Al4C3 powder application

Aluminum carbide Al4C3 powder is used in metallurgy, catalysts and methane production. Additionally, typical applications for aluminum carbide include:

1. Aluminum carbide particles finely dispersed in an aluminum matrix can reduce the creep tendency of the material, especially when used in combination with silicon carbide particles.

2. Aluminum-aluminum carbide composites can be made by mechanical alloying, grinding together aluminum powder and graphite particles.

3. Aluminum carbide can be used as abrasive for high-speed cutting tools, and its hardness is almost the same as topaz.

4. Aluminum carbide is also used in fireworks, for example, to achieve the effect of fireflies.

Aluminum carbide Al4C3 powder price

The price of aluminum carbide Al4C3 powder will vary randomly with the production cost, transportation cost, international situation and the market supply and demand of aluminum carbide Al4C3 powder. Tanki New Materials Co.,Ltd aims to help various industries and chemical wholesalers find high-quality, low-cost nanomaterials and chemicals by providing a full range of customized services. If you are looking for aluminum carbide Al4C3 powder, please feel free to send an inquiry for the latest information.

Aluminum carbide Al4C3 powder suppliers

As a global supplier of aluminum carbide. Tanki New Materials Ltd. has extensive experience in the performance, application and cost-effective manufacturing of advanced and engineered materials. The company has successfully developed a series of powder materials (including boron carbide, titanium carbide, titanium carbide, etc.), high-purity targets, functional ceramics and structural devices, and provides OEM services.