High-Strength Silicon Nitride Ceramic Stepped Bolt - Reliable Connection Solution For Extreme Environments

High-Strength Silicon Nitride Ceramic Stepped Bolt - Reliable Connection Solution for Extreme Environments

Product Overview

This product is a precision-machined stepped bolt made of high-performance silicon nitride ceramic, specifically designed for high-temperature, highly corrosive, and precision mechanical environments. The bolt features an overall gray-black matte texture, with a structure comprising an external threaded cylinder, a smooth transition section, and a hexagonal nut with a slotted design, combining installation convenience with structural stability. Silicon nitride ceramic, with its high hardness, low density (3.2-3.3 g/cm³), and high-temperature resistance (up to 1200℃), significantly outperforms metal materials, making it suitable for high-end applications such as semiconductors and aerospace.

Core Advantages

1. Exceptional Mechanical Performance

   • Flexural strength ≥800 MPa, fracture toughness 6-8 MPa·m¹/², hardness ≥1500 Hv, capable of withstanding high loads and impact.

   • Low friction coefficient (0.1-0.3) and self-lubricating properties, reducing wear and extending service life 5-10 times longer than metal bolts.

2. Adaptability to Extreme Environments

   • High-temperature resistance: Stable operation in oxidizing atmospheres up to 1200℃, withstanding thermal shock temperature differences exceeding 800℃.

   • Corrosion resistance: Resists strong acids, alkalis, and organic solvents (except hydrofluoric acid), suitable for chemical and semiconductor cleanrooms.

   • Electrical insulation: Room temperature resistivity ≥10¹⁵ Ω·cm, avoiding electromagnetic interference.

3. Precision Structure and Lightweight Design

   • Thread tolerance ±0.005 mm, hexagonal nut compatible with standard tools, density only 3.2 g/cm³, 60% lighter than steel components.

Typical Applications

• Semiconductor Manufacturing: Fasteners for wafer handling arms, sealing connections for vacuum chambers, resistant to organic solvent erosion.

• Aerospace: High-temperature zone components for engines, sealing bolts for liquid hydrogen pumps, stable from ultra-low to high temperatures.

• Energy and Chemical Industries: Valves for liquefied natural gas (LNG), sealing systems for nuclear reactors, resistant to high pressure and corrosive media.

• Precision Machinery: Preload bolts for high-speed spindle bearings, replacing metal to reduce inertia and thermal deformation.

Specification Table

Manufacturing Process

1. Powder Processing: High-purity α-Si₃N₄ powder (particle size ≤1μm) mixed with sintering additives.

2. Forming Process: Cold isostatic pressing (CIP) for preliminary shaping, CNC engraving for threads and slots.

3. Sintering Technology: Gas pressure sintering (1700-1900℃, nitrogen atmosphere), density >99%.

4. Precision Machining: Diamond grinding and polishing, surface roughness Ra≤0.2 μm.

5. Quality Inspection: Ultrasonic flaw detection, dimensional inspection with CMM, Weibull modulus ≥12.

Usage Instructions

1. Installation Specifications

   • Use a torque wrench with recommended preload force ≤30 N·m to avoid brittle fracture from overloading.

   • When mating with metal components, adding a BN coating is recommended to reduce thermal mismatch stress.

2. Environmental Limitations

   • Avoid contact with hydrofluoric acid or hot concentrated alkali solutions (pH＞12).

   • Control temperature change rate to ≤200℃/minute.

3. Maintenance Recommendations

   • Inspect thread wear every 1000 hours of operation, clean with anhydrous ethanol.

After-Sales Service

• Quality Assurance: 18-month product warranty, lifetime technical support.

• Customization Services: Support for non-standard thread sizes and head structure customization, delivery period 15-30 days.

• Emergency Response: Fault analysis within 24 hours, replacement parts shipped within 48 hours.

FAQ

Q1: Is performance stable in liquid hydrogen environments (-253℃)?
A1: Yes, silicon nitride does not undergo brittle transition at ultra-low temperatures, with strength and toughness even exceeding room temperature performance. It has passed 10⁷ cycle tests for liquid hydrogen pump seals.

Q2: Can it be directly mated with aluminum alloy components?
A2: It is recommended to add a flexible gasket, as the thermal expansion coefficient of aluminum (23×10⁻⁶/℃) is much higher than that of silicon nitride (3.2×10⁻⁶/℃), requiring compensation for thermal displacement.

Q3: What is the maximum tensile load?
A3: The ultimate tensile load for an M6 specification bolt is ≥35 kN, with a recommended safety factor of 3.

We are a company with many years of experience in the production of special precision ceramics and the ability to design, manufacture, process and sell structural and functional parts of various special precision ceramics.

Deyu Precision Ceramics Technology Co., Ltd. has many years of experience in producing special precision ceramics, and has the ability to design, manufacture, process and sell structural and functional parts of various special precision ceramics. At present, the company has production and processing equipment such as dry press, isostatic press, experimental furnace, flat kiln, machining center, surface grinder, universal internal and external grinder, centerless grinder and laser cutting machine, as well as complete high-precision testing equipment such as high-precision projector, three-dimensional tester, metallographic microscope, hardness tester and densitometer.

With advanced production technology and complete production facilities, the company is one of the few domestic enterprises that can produce special precision ceramic structural parts and functional parts with machining accuracy less than 2 microns, and has strong core competitiveness in the same industry in China.

Advantages of the company: 1. National new technology enterprises; 2. The company has a municipal R&D center; 3. Cooperation with domestic key universities and research institutes; 4. Design, molding, sintering and precision processing; 5. The products cover alumina, zirconia, silicon nitride, silicon carbide and other precision ceramics; 6. Precision plus technology.

The company has always been standing in the position of customers to solve problems, focusing on the principle of quality and delivery time, adhering to the business philosophy of "integrity, innovation and reassurance", and sincerely looking forward to cooperating with you.