Alumina Mo Mn Ceramic Metallization Insulator for Vacuum Power Feedthroughs

Product Description

Alumina Mo Mn Ceramic Metallization insulator for Vacuum Power Feedthroughs
 

Product Description

What is Ceramic Structural Parts

Ceramic structural parts are precision ceramic parts obtained by using high-purity special ceramic materials, through rigorous structural design and appropriate forming method, and processed. 

Is it Good to Use Ceramic Structural Parts?

You can see the advantages of ceramic structural parts through the comparative table between ceramic, metal, and polymer below.

Property	Ceramic	Metal	Polymer
Hardness	High	Low	Bad
Elastic Modulus	High	Good	Low
High Temperature Resistance	High	Low	Bad
Thermal Expansion	Low	Good	Good
Malleability	Low	Good	Good
Corrosion Resistance	Good	Low	Low
Electrical Conductivity	Low	Good	Low
Density	Average	High	Low
Thermal Conductivity	Average	Good	Low

 

Why do Metallization on the Surface of Ceramic Structural Parts?

Ceramic metallization is the combination of two materials with different properties. The ceramic material has the characteristics of high strength, high hardness, high-temperature resistance, corrosion resistance, and good insulation performance, while the metal material has the characteristics of good thermal conductivity, strong electrical conductivity, and good ductility.

The combination of ceramic and metal materials not only achieves complementary advantages in performance but also broadens their respective application ranges.
 
Production Process

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

 

Forming	Finishing	Metallization
We will choose the most suitable forming method on the basis of saving costs and ensuring quality.	In order to achieve the precision of the product, most ceramic structural parts need further finishing treatment after the sintering 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.

Which Metallization Processes We Support?

Jinghui has been focusing on the production and processing of precision ceramic structural parts for more than ten years. Our metallization options include Ag, Mo-Mn W, etc., and the surface coatings include Au, Ni, Al, Ti, Cu, Cr, etc.

Our products are widely used in optical communications, medical, lighting, machinery, aviation, aerospace, petroleum, chemical, textile, consumer electronics, electrical appliances, smart wear, and other fields.

Introduction to Mo-Mn Method

The metal powder sintering method is the most widely used ceramic metallization method in electric vacuum technology. According to the different types of metal powder, it can be divided into two types: refractory metal and non-refractory metal. The former is mainly composed of W and Mo, while the latter has Au, Ag, Pt, Pd, and Cu.

According to the metallization temperature, it can be divided into high-temperature method (1200-1600 ºC), ultra-high-temperature method (above 1600 ºC), and low-temperature method (900-1200 ºC). The most commonly used method is the high-temperature method, among which the Mo-Mn method is more widely used.

As shown below, the process of the Mo-Mn method is roughly: pretreatment of ceramic parts, preparation and coating of metallization layer formula, sintering of metallization layer, and electroplating on metallization layer.

Advantages of Mo-Mn Method

1. High bonding strength, high air tightness, high reliability, and good heat resistance.
2. The finished product has dual characteristics of ceramic and metal.

Product Parameters

The following are the material properties of 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

Why Choose Us

Our ceramic parts with core competitiveness include ceramic tubes, ceramic rods, ceramic substrates, ceramic grinding burrs, ceramic seals, ceramic nozzles, textile ceramics, etc., which are widely used in furnaces, semiconductors, aerospace, pump valves, new energy, fluid control, mechanical wearing parts, and other fields. You are welcome to consult us for business.