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Graphite Mould

Customized Graphite Crucible &Graphite Mould For the Melting & Casting Machine

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Product Details

[Graphite Mold]

Graphite mold is a molding tool made of graphite material. With the characteristics of graphite such as high temperature resistance, fast thermal conductivity and high chemical stability, it is widely used in metal（Gold,Silver,Copper.etc.） casting, semiconductor processing, glass molding, powder metallurgy and other fields. The following is a detailed analysis of graphite mold:

1. Core Characteristics

High temperature resistance:The melting point of graphite is as high as 3650°C, and it can work below 1600°C for a long time. It is suitable for casting high-temperature molten metals (such as gold, silver, copper, and aluminum).

High thermal conductivity:The thermal conductivity is 2 to 5 times that of steel, which can quickly transfer heat, shorten the cooling time of metal, and improve production efficiency.

Low thermal expansion coefficient:The dimensional stability is good at high temperature, the mold is not easy to deform, and the molding accuracy is guaranteed (±0.05mm).

Self-lubricating property:The graphite layered structure can reduce friction with the metal liquid, demolding is smooth, and the risk of sticking is reduced.

Chemical inertness:Acid and alkali corrosion resistance, does not react with most molten metals, and avoids contamination of metal purity.

2.Application.

Precious metal casting:Jewelry: Used for lost wax casting or direct casting of gold and silver, making rings, pendants, etc. with complex patterns, with high surface finish.
Investment gold bars/coins: Casting standardized gold bars and silver coins to ensure consistent weight and shape.

Semiconductor industry:Crucibles for growing single crystal silicon and polycrystalline silicon, as well as graphite boats and fixtures in wafer processing.

Glass industry:Pressure molding molds for optical glass and bottle glass, resistant to high temperatures and non-sticky to molten glass.

Powder metallurgy:Sintering molds for cemented carbide and diamond tools, withstand high pressure and high temperature environments.

Continuous casting:Continuous casting crystallizers for metals such as copper and aluminum to improve the surface quality of the ingot.

3. Processing and selection

Material grade:Isostatic graphite: high density (≥1.8g/cm³), high strength, suitable for precision casting.

Molded graphite: low cost, used in general industrial scenarios.

Anti-oxidation coated graphite: SiC or ceramic layer coated on the surface to extend the life of the mold.

Processing technology:CNC precision engraving: to achieve complex cavity structure, the accuracy can reach 0.01mm.

Surface polishing: Ra≤0.4μm, reduce the flow resistance of molten metal.

Key parameters for selection:Density (determines wear resistance) | Particle size (affects surface roughness) | Flexural strength (≥30MPa) | Anti-oxidation temperature (whether coating is required).

4. Feature

High temperature resistance, good thermal stability, high brittleness, poor impact resistance
Fast thermal conductivity, high production efficiency, easy to oxidize in high humidity environment
Excellent demoulding performance, high precision processing cost
Reusable (life 50-200 times)

5. Precautions for use and maintenance

Preheating treatment:Before the first use, it is necessary to slowly heat up to the working temperature (such as 200°C/h) to avoid thermal stress cracking.

Mold release agent selection:Coat boron nitride or graphite emulsion to further reduce metal adhesion.

Cleaning and maintenance:Clean up residual metal slag after use (can be cleaned by ultrasonic cleaning or high-pressure gas blowing).

Store in a dry environment to prevent moisture absorption and oxidation.

Prolong Life:Regularly check the surface cracks or wear of the mold and replace it in time to avoid affecting product quality.

Parameter of mould

Description	Size(mm)
Description	L1	W1	H1	L2	W2	H2
100g	55	40	20	35	20	10
200g	70	45	20	50	25	10
250g	67	50	26	47	25	16
300g	70	57	20	50	37	10
400g	75	67	20	50	47	10
500g	70	67	26	50	47	16
1kg	135	42	32	115	22	22
2kg	160	48	38	140	28	28
3kg	175	52	42	155	32	32

* The mould can be customized to desired shape

Click the link to get the Crucible size

Feature

1. Thermal stability. According to the use conditions of graphite crucible, we will specially design the production procedure to ensure the reliability of product quality.

2. Corrosion resistance: according to the use conditions of graphite crucible for quenching and heating, we will specially design production procedures to ensure the reliability of product quality. Uniform and fine basic design can delay the corrosion of crucible.

3. Impact resistance: the basic design of graphite crucible is uniform and fine, which can delay the corrosion of crucible. Graphite crucible can withstand high thermal shock, so any process can be carried out.

4. Acid resistance: graphite crucible can withstand high thermal shock, so any process can be carried out. The addition of special materials will greatly improve the quality of crucible, especially the acid resistance index, and prolong the service life of graphite crucible.

5. High thermal conductivity: high content of fixed carbon ensures good thermal conductivity of crucible. High content of fixed carbon ensures good thermal conductivity, shortens dissolution time and significantly reduces energy consumption.

6. Control metal pollution. Strictly control the material composition to ensure that the graphite crucible will not pollute the metal during dissolution.

7. The quality is stable. High pressure molding technology and quality assurance system will fully ensure the stability of quality.