Overview of Aluminum Oxide Bolts and Nuts
Aluminum oxide bolts and nuts are ceramic fasteners with alumina (Al₂O₃) as the main ingredient, which maintains stable performance in harsh environments by virtue of its high hardness, abrasion resistance, corrosion resistance, insulation, and high-temperature resistance. Its core advantages are reflected in the following: material purity: 99.8% high purity recrystallized alumina is usually used, balancing the cost and comprehensive performance; performance advantages: temperature resistance up to 1650 ℃, hardness is second only to diamond (Moh's hardness level 9), excellent insulation (for high-voltage environments); lightweight: the density of only 1/3 of the metal, reducing the load on the equipment while improving reliability.
aluminum oxide bolts and nuts
High temperature resistance and thermal stability
Continuous working temperature: 1500-1650℃, far exceeding the temperature limit of metal fasteners (e.g., stainless steel is about 800℃); Thermal shock resistance: it can withstand rapid temperature changes (e.g., from high temperature to room temperature), and it is not easy to crack or embrittlement.
Chemical and environmental resistance
Corrosion resistance: extremely resistant to acids, alkalis, salts and organic solvents (except hydrofluoric acid), suitable for chemical reactors, marine equipment and other corrosive environments; non-magnetic: no metal magnetic interference, to meet the special needs of precision electronic equipment, medical imaging instruments (such as MRI).
Mechanical and Electrical Properties
Hardness and strength: Vickers hardness 1800-2200 HV, compressive strength up to 2500 MPa, but lower tensile strength (need to avoid pure tensile load); Insulation: dielectric strength >15 kV/mm, volume resistivity >10¹⁴ Ω・cm, effective isolation of high-voltage currents, preventing arc discharge.
Specification Parameter Table of Aluminum Oxide Bolts and Nuts
| Specification |
Details |
Other Information |
| Material |
99.8% high-purity recrystallized alumina ceramic |
High-purity alumina ceramics are the most common type, with the greatest balance of cost-effectiveness, mechanical, and thermal properties. Other alumina compositions are available upon request. |
| Color |
White |
- |
| Temperature Resistance |
Up to 1650°C (3000°F) |
Alumina ceramic bolts are among the most thermally resistant bolts available and are suitable for demanding high-temperature applications. |
| Corrosion Resistance |
Excellent corrosion resistance to acids, solvents, salts, and organics |
- |
| Electrical Insulation |
Excellent electrical insulator |
Non-conductive electrical properties make alumina ceramic bolts suitable for high-voltage applications. |
| Mechanical Properties |
High hardness, good strength, and wear resistance |
The hardness of alumina ceramics is second only to diamond, with a Mohs hardness of approximately 9.0. Their compressive strength is excellent, but their tensile strength and flexural strength are relatively low. |
| Thread Standards |
Metric and imperial thread standards are available |
- |
| Sizes |
Available in various sizes, such as M4 (5mm length), M6, etc. |
Custom dimensions can be requested. |
| Surface Treatment |
Generally no special surface treatment required, as the ceramic material itself is corrosion-resistant and insulating |
- |
| Applications |
Widely used in high-temperature environments, such as kilns, smelting equipment, and chemical reactors; also used in high-voltage electrical equipment and corrosive environments |
- |
| Standards |
There are no unified international standards for alumina ceramic bolts and nuts. Specifications and dimensions are typically determined based on user requirements and the manufacturer's standards |
- |
|
Applications of Aluminum Oxide Bolts and Nuts
Aerospace field
Engine parts connection: used in turbine blades, combustion chambers and other high-temperature areas, replacing metal bolts to avoid oxidation failure; electronic equipment insulation: fixing the circuit boards of aviation instrumentation and radar systems to prevent electromagnetic interference and the risk of power leakage.
Electronics and Power Industry
High-voltage equipment insulation fixed: in substations, high-voltage cable terminals as insulation fasteners, withstand more than 10kV; semiconductor manufacturing: used in photolithography, etching machine precision mechanical structure, to avoid metal particles contaminated wafers.
Chemical and Marine Engineering
Corrosive environment equipment connection: in strong acid (such as sulfuric acid), strong alkali (such as sodium hydroxide) medium pipeline, instead of stainless steel bolts to prevent corrosion fracture; deep-sea equipment: resistance to seawater corrosion and biological attachment, for underwater robots, marine monitoring equipment fastening.
New energy and automobile industry
High-voltage systems for electric vehicles: fixing battery packs and motor controllers, providing electrical insulation and thermal management support; Fuel cell stacks: maintaining connection stability at high temperatures (> 800 ℃), high humidity, and resisting hydrogen corrosion.
Medical and Precision Instruments
Medical equipment assembly: used for fixing non-magnetic parts of CT/MRI equipment to avoid interference with imaging accuracy; biological implantation assistance: the biocompatibility of high-purity alumina allows it to be used as a fixation component for orthopedic implants (special surface treatment is required).
Company Profile
Luoyang Tongrun Nano Technology Co. Ltd. (TRUNNANO) is a trusted global chemical material supplier & manufacturer with over 12-year-experience in providing super high-quality chemicals and nanomaterials, including boride powder, nitride powder, graphite powder, ceramic products, 3D printing powder, etc.
The company has a professional technical department and Quality Supervision Department, a well-equipped laboratory, and equipped with advanced testing equipment and after-sales customer service center.
If you are looking for high-quality Ceramic Products please feel free to contact us or click on the needed products to send an inquiry.
Applications of Ceramic Products
Process of Ceramic Products
Payment Term
T/T, Western Union, Paypal, Credit Card etc.
Shipment Term
By air, by sea, by express, as customers request.
5 FAQs of Aluminum Oxide Bolts and Nuts
Q1: How to choose the right aluminum oxide bolt nut?
Load assessment: Prioritize shear/tension loads to avoid exceeding the material's tensile strength (usually ≤300 MPa); Environmental matching: 99.8% purity for high-temperature scenarios, hydrophobic surface treatment for high humidity environments; Insulation requirements: Confirm the dielectric strength for high-voltage applications (≥20 kV/mm is recommended).
Q2:What should be paid attention to when installing alumina bolts and nuts?
Before installation, check whether the threads are damaged or have impurities, etc., and ensure that the bolts and nuts match the threaded holes of the connected parts well. During installation, the tightening torque must be controlled to avoid damage to the bolts and nuts or loose connections due to excessive torque.
For some special applications, such as in a vibrating environment, anti-loosening measures such as locking nuts and stop washers can be considered.
Q3: Compared with metal bolts, what is the cost difference between aluminum oxide bolts and nuts?
Initial cost: the cost of aluminum oxide bolts is about 3-5 times that of stainless steel bolts, but the life expectancy can be more than 10 times. Comprehensive cost: in the corrosive/high-temperature environment, the frequency of replacement is reduced by 80%, the maintenance cost is significantly reduced, and the long-term cost-effectiveness is better.
Q4: Does aluminum oxide bolt and nut support direct connection with metal parts?
Direct contact is not recommended: it needs to be isolated by ceramic washers or insulating sleeves to prevent electrochemical corrosion (aluminum and metal contact is prone to form a primary battery); transition design: a combination of “ceramic bolts + metal nuts” can be used, but it needs to be ensured that the metal parts are not subject to the main load.
Q5: Can alumina bolts and nuts be recycled after scrapping?
Material recycling: Alumina ceramics can be reused after crushing and purification, and their environmental attributes are better than metal-plated fasteners. Professional processing: It is recommended to return to the original factory for recycling to avoid mixing metal impurities affecting the performance of recycled materials.
