Graphite sintering moldIt is a mold commonly used in metal sintering processes for manufacturing high-strength and high-precision metal parts. The tool is made by filling metal powder into a mold, and then applying high temperature and high pressure for sintering, so that the metal powder particles are combined into dense metal parts. It has good thermal conductivity and high temperature stability, and can withstand the effects of high temperature and high pressure, ensuring that the metal powder undergoes uniform pyrolysis and sintering during the sintering process, forming high-quality parts.
Graphite sintering moldThe main characteristics are:
1、 Excellent high temperature resistance
High melting point: The sublimation temperature of graphite can reach up to 3650 ° C, and it can work stably for a long time above 2000 ° C in an oxygen free or inert atmosphere, far exceeding most metal and ceramic molds.
Good high-temperature strength: It can maintain high mechanical strength and shape stability even at high temperatures, and is not easily softened or deformed.
2、 Good thermal stability and thermal shock resistance
Low thermal expansion coefficient: The thermal expansion coefficient of graphite is very small, and the size change is minimal when heated, ensuring the dimensional accuracy and stability of the mold during the sintering process.
Strong thermal shock resistance: able to withstand rapid heating and cooling (thermal shock) without cracking, suitable for processes that require rapid sintering or cooling.
3、 Excellent thermal and electrical conductivity
High thermal conductivity: Graphite is a good conductor of heat, which can quickly and uniformly transfer heat to the workpiece, reduce temperature gradients during sintering, and improve product uniformity and density.
High conductivity: It can be used in spark plasma sintering (SPS) or electric sintering processes, directly heating molds and workpieces with electricity to achieve ultra fast sintering.
4、 Good self-lubricating and demolding performance
Natural lubrication: The layered structure of graphite gives it self-lubricating properties and a low coefficient of friction.
Easy demolding: After sintering, the workpiece is not easily adhered to the graphite mold, making it easy to remove and reducing damage to the sintered part, especially suitable for complex shaped workpieces.
5、 High chemical stability
Corrosion resistance: It has good chemical inertness to most metal melts (such as Fe, Cu, Ni, Co, etc.) and molten salts in an inert atmosphere or vacuum, and is not prone to reactions.
Non wetting: Most metal melts do not wet the surface of graphite, reducing mold sticking.
Attention: Graphite is prone to oxidation in high-temperature oxidizing atmospheres (starting at>400 ° C), so it must be used under vacuum or inert gas protection (such as Ar, N ₂).
6、 Lightweight and easy to process
Low density: The density of graphite is about 1.7-1.9 g/cm ³, much lower than that of metal molds, reducing equipment load.
Easy to process: Moderate hardness, can be processed into various complex shapes (such as irregular shapes, deep holes, threads, etc.) using conventional mechanical processing methods such as turning, milling, drilling, and grinding, with relatively low processing costs.
7、 A certain degree of elasticity and impact resistance
Graphite has certain elasticity and toughness, can withstand certain mechanical impacts and vibrations, and is not easily brittle (compared to ceramic molds).
8、 Reusability
Under reasonable use and maintenance (such as avoiding oxidation and collision), graphite sintering molds can be reused multiple times, reducing production costs.
The service life depends on the sintering material, temperature, atmosphere, and operating specifications.