Among all industrial ceramic materials, silicon carbide has become the preferred one for extreme operating conditions. SiC provides excellent high-temperature and corrosion resistance. Pressureless Sintered Silicon Carbide, or PSSiC, is an important branch of silicon carbide. Achieving densification without external pressure, PSSiC is widely employed in various industries.
This article will provide an introduction to the definition, properties, limitations, and applications of PSSiC. After reading this article, you will be able to determine whether PSSiC meets your production requirements.
Definition and Process of PSSiC
The full name of PSSiC is Pressureless Sintered Silicon Carbide. It is an advanced ceramic material made by sintering high-purity silicon carbide powder with sintering additives. Unlike reaction bonding or hot pressing, PSSiC does not require external pressure. Through sintering additives and high temperatures of about 1900℃-2200℃, PSSiC achieves dense bonding. It helps produce parts with a density close to the theoretical.
Based on the mechanism of the additives, PSSiC has two categories: Solid-State Sintered Silicon Carbide (SSiC) and Liquid-Phase Sintered Silicon Carbide (LSiC).
SSiC relies on additives to form a solid solution with silicon carbide, driving the sintering process. It has a pure grain boundary structure with stable high-temperature strength.
LSiC promotes sintering through the eutectic liquid phase. It has a lower sintering temperature compared to SSiC. Therefore, the results have finer grains and better fracture toughness.
The PSSiC production process requires high precision. Its main steps are shown below.
PSSiC Production Process (in Simple)Key Characteristics of PSSiC
As a high-performance industrial ceramic, PSSiC possesses properties matching extreme working conditions. Compared to other types of silicon carbide, PSSiC offers some key advantages.
Excellent High-Temperature Resistance
PSSiC exhibits outstanding high-temperature resistance. In an inert environment, PSSiC can reach a long-term service temperature of 1600℃. In the air, it can reach above 1400℃. The oxidation layer on PSSiC provides protection, making it suitable for various high-temperature operating conditions.
Superior Thermal Performance
PSSiC has excellent thermal shock resistance. Silicon carbide products made of PSSiC can withstand intense temperature fluctuations without cracks and deformation. It can help you achieve uniform heat transfer.
High Hardness and Wear Resistance
PSSiC possesses extremely high Mohs hardness. It results in exceptional wear and erosion resistance. Using PSSiC can extend the service life of equipment components effectively and reduce maintenance costs.
Chemical Inertness
PSSiC exhibits strong chemical stability. It can resist erosion from strong acids, strong alkalis, and molten metals. PSSiC parts can solve the problems of corrosion and leakage of metallic ones.
Structural Stability
PSSiC has high density and low porosity. Its stable structure can prevent the penetration of media. Under high-pressure and high-temperature conditions, PSSiC products are resistant to deformation. They can maintain highly stable strength and toughness under a harsh industrial environment.
Here is a table shows the key performance parameters of PSSiC. You can review this table to find whether to PSSiC is suitable for your industry.
| Item | Unit | Data |
| PSSiC | ||
| Density | g/cm3 | 3.12 |
| Fracture Toughness | MPa·m1/2 | 3.2 |
| Bending Strength 20℃ | Mpa | 410 |
| Bending Strength 1,400℃ | Mpa | 410 |
| Modulus of Elasticity | Gpa | 410 |
| Coefficient of Thermal Expansion | K-1×10-6 | 4.7 |
| Thermal Conductivity 20℃ | W/m·k | 110 |
| Thermal Conductivity 1,000℃ | W/m·k | 45 |
Limitations of PSSiC
PSSiC still has certain limitations. High sintering temperature up to 1900℃ will bring higher energy consumption and costs. Secondly, PSSiC is not suitable for high loads or strong impact conditions. Moreover, because of its high hardness and brittleness, the processing difficulty of PSSiC is relatively high. Achieving sintering densification is also challenging. Large-scale PSSiC products are prone to non-uniform performance, making the preparation more difficult.
Applications of PSSiC
Compared to RBSiC, PSSiC has a higher purity with SiC ≥98%. It maintains excellent high-temperature strength even above 1600℃. It also possesses good corrosion resistance and thermal conductivity. PSSiC is widely used in high-end industrial fields.
Chemical Industry
PSSiC has excellent corrosion resistance and high-temperature resistance, perfectly solving the problems in chemical production. PSSiC corrosion-resistant heat exchange tubes can withstand erosion from strong acids and strong alkalis. Using them will greatly reduce the risk of leakage and improve heat exchange efficiency.
PSSiC high-temperature nozzles can withstand erosion at temperatures above 1600℃. It can maximize the service life of your equipment and reduce maintenance costs. In addition, mechanical seal rings in pumps and valves can also use PSSiC. It helps you reduce wear and leakage, assisting you in dealing with extreme corrosion conditions.
Newthink PSSiC Burner Nozzle DrawingSemiconductor Manufacturing
PSSiC’s high purity (≥98%) meets the strict requirements of wafer production. Semiconductor manufacturing needs extremely high standards of material purity and cleanliness. PSSiC semiconductor wafer carriers are suitable for high-temperature processes such as wafer sintering and etching.
Besides preventing contamination, with its high-precision processing capabilities, PSSiC wafer carriers provide stable support. It can improve semiconductor product yield. The high-voltage resistance and low-loss characteristics make it widely used in semiconductor power devices.
PSSiC Wafer Carrier ApplicationsMilitary
PSSiC possesses extremely high hardness, impact toughness, and lightweight. It is an ideal material for high-end ballistic armor. Military equipment has strict requirements for armor’s protective performance and weight. Compared to metal one, PSSiC armor offers superior protection and lower weight. It can resist the impact of high-speed projectiles effectively and reduce the loads, providing reliable defense.
PSSiC ArmorHigh-End Optics
PSSiC has a low expansion coefficient, high structural stability, and excellent thermal shock resistance to meet your requirements in the high-end optics field. Components such as optical mirrors place high demands on the flatness, thermal stability, and structural strength of the substrate. PSSiC optical mirror substrates maintain high precision even in extreme temperature differentials. By using it, you will not need frequent calibration. Therefore, PSSiC optical mirrors are widely used in aerospace remote sensing and high-end optical instrumentation.
Conclusion
PSSiC has become an ideal choice for high-end industrial fields. Its unique process without external pressure satisfies the special needs of various high-end productions. If your industry has highly strict requirements for material purity, high-temperature strength, and corrosion resistance, PSSiC is undoubtedly a highly cost-effective choice. Until now, PSSiC has achieved large-scale application in fields like chemical engineering, semiconductors, and the military.
Unsure whether PSSiC is suitable for your operation? Feel free to contact Newthink New Materials. With 14 years of experience in the advanced ceramics industry, we can help you match the appropriate type of silicon carbide quickly.
Thanks for your reading. Hope this article will be helpful to you.
FAQs
- What is sintering?
Sintering is one of the thermal processes. It bonds particles into solid by heat, turning powder into a dense, strong part.
- What is pressureless sintering?
It is a densification process without external pressure. Materials bond at high temperatures with additives.
- What is silicon carbide material?
Silicon carbide is an advanced industrial ceramic. It performs excellently in high-temperature and corrosive environments, ideal for harsh conditions.
- What is pressureless sintering silicon carbide (PSSiC)?
PSSiC is a high-purity ceramic made without external pressure. It maintains exceptional strength even above 1600℃.
- Why is sintering necessary?
Sintering creates structural integrity. It decreases porosity to achieve high density, ensuring the material withstands stress.
- What are the benefits of SiC?
SiC possesses high hardness with excellent wear, corrosion resistance, and thermal performance. SiC can remain stable even under extreme heat. It also provides excellent chemical inertness.
