Mo-Mn Metallization High Quality 95 Alumina Ceramic Insulator for Vacuum Electronics

• Application: Aerospace, Electronics, Medical
• Purity: 95%
• Type: Ceramic Part
• Product Name: Metallized Alumina Ceramics
• Color: White
• Surface Metallization Process: Mo-Mn Metallization
• Model NO.: Customized
• Feature: High Performance and High Precision
• Transport Package: Vacuum Packaging
• Specification: As per the drawing
• Trademark: JingHui
• Origin: China
• HS Code: 8547100000
• Production Capacity: 50000 Pieces/Month

Product Description

Mo-Mn Metallization High Quality 95 Alumina Ceramic Insulator for Vacuum Electronics


Production Process

Our product production is mainly divided into 3 steps, forming - finishing - metallization. The production flow chart is shown below.
 

1. Forming Method

There are mainly Dry Pressing, Hot Pressing, Isostatic Pressing, and Ceramic Injection Molding (CIM), each of which has its own advantages and disadvantages. We will choose the most suitable forming method on the basis of saving costs and ensuring quality.
 

2. Finishing Process

In order to achieve the precision of the product, most ceramic structural parts need further finishing treatment after the sintering process. The main finishing processes we use are machining (lapping, polishing...) and glazing.

3. Metallization Process

Metallization of ceramics refers to the creation of thin metal layers (films) on the surface of ceramics. After the surface of the ceramic material is metallized, it has both the characteristics of ceramics and the properties of metal.


Introduction to Mo-Mn Method

The Mo-Mn method is to coat metal powders such as Mo powder and Mn powder on the ceramic surface, and then sinter at high temperature in a reducing atmosphere (hydrogen gas), thereby forming a metal layer on the ceramic surface. Because Mo and ceramics have similar thermal expansion coefficients, the thermal stress after bonding is small, so the bonding strength between the metal film and ceramics is high.

The brief process of Mo-Mn method is shown in the picture below.


We can produce metallized ceramic structural parts of various specifications according to customers' drawings.


Product Applications

Metallized ceramics are used in electronics and electrical industries. The application include:

Vacuum relays, Vacuum electrical feedthroughs, Vacuum electrical switch, electron tubes, gas discharge tubes, diode housings, etc.

Product Parameters

The following is the material properties of our alumina ceramic structural parts.
 

Category	Property	Unit	99.8% Al2O3	99.5% Al2O3	99% Al2O3	95% Al2O3	94.4% Al2O3
Mechanical	Density	g/cm^3	≥3.95	≥3.90	≥3.85	≥3.65	≥3.60
	Water absorption	%	0	0	0	0	0
	Vickers hardness	HV	1700	1700	1700	1500	1500
	Flexural strength	Mpa	≥ 390	≥ 379	≥ 338	≥ 320	≥ 312
	Compressive strength	Mpa	≥ 2650	≥ 2240	≥ 2240	≥ 2000	≥ 2000
	Fracture toughness	Mpam^1/2	4-5	4-5	4-5	3-4	3-4
Thermal	Max. Service temperature (non-loading)	ºC	1750	1675	1600	1500	1500
	CTE (Coefficient of thermal expansion) 20-800ºC	1×10^-6/ºC	6.5-8.2	6.5-8.0	6.2-8.0	5.0-8.0	5.0-8.0
	Thermal shock	T (ºC)	≥ 200	≥ 200	≥ 200	≥ 220	≥ 220
	Thermal conductivity 25ºC	W/(m·k)	31	30	29	24	22.4
	Specific heat	1×10^3J/(kg·k)	0.78	0.78	0.78	0.78	0.78
Electrical	Volume resistivity 25ºC	ohm·cm	> 1×10^14	> 1×10^14	> 1×10^14	> 1×10^14	> 1×10^14
	300ºC		1×10^12	1×10^12	8×10^11	10^12-10^13	10^12-10^13
	500ºC		2×10^12	5×10^10	2×10^9	1×10^9	1×10^9
	Dielectric strength	KV/mm	20	19	18	18	18
	Dielectric constant (1Mhz)	(E)	9.8	9.7	9.5	9.5	9.5

Product Recommendations

Thank you for your visit. We can produce and process various special-shaped and high-precision ceramic structural parts according to your requirements.

We are confident that we can fulfill your product requirements well. Welcome to order with drawings or samples, and look forward to becoming your reliable partner!