INDUSTRY COMPONENT

Cathode

A cathode is the electron-emitting electrode in an electron gun, essential for generating electron beams in vacuum tube devices.

Component Specifications

Definition
In industrial electron guns, the cathode is a thermionic or field emission component that emits electrons when heated or subjected to an electric field. It serves as the negative electrode where electron flow originates, typically made from materials with low work functions to facilitate efficient electron emission under high vacuum conditions.
Working Principle
Operates on thermionic emission (heated cathode) or field emission (cold cathode) principles. When sufficient thermal energy or electric field is applied, electrons overcome the material's work function barrier and are emitted into the vacuum, forming a controlled electron beam accelerated toward the anode.
Materials
Tungsten, thoriated tungsten, lanthanum hexaboride (LaB6), or oxide-coated nickel alloys. High-purity materials with melting points above 2000°C for thermionic cathodes; carbon nanotubes or sharp metal tips for field emission cathodes.
Technical Parameters
ParameterTypical rangeNotes & selection driver
Lifetime1000-10000 hours
Work Function2.0-4.5 eV
Emission Current0.1-1000 mA
Vacuum Requirement<10^-6 mbar
Operating Temperature1500-2800 K (thermionic)

Ranges are indicative industry figures for RFQ preparation, not a supplier commitment. Confirm every value and standard with the legal manufacturer before ordering.

Standards
ISO 17560, DIN 54115

Parent Products

This component is used in the following industrial products

Engineering Analysis

Risks & Mitigation
  • Thermal degradation
  • Emitter poisoning from residual gases
  • Arc discharge in poor vacuum
  • Work function increase over time
FMEA Triads
Trigger: Contamination from oil backstreaming or outgassing
Failure: Reduced emission current, unstable beam
Mitigation: Implement strict vacuum protocols, use getters, and perform regular cathode conditioning
Trigger: Overheating due to insufficient cooling or excessive current
Failure: Cathode deformation or material evaporation
Mitigation: Install temperature monitoring, use pulse operation for high currents, and ensure proper heat sinking

Industrial Ecosystem

Compatible With

Typical Suppliers & Equivalents

Compliance & Inspection

Tolerance
±5% emission current stability, ±0.1 mm dimensional accuracy
Test Method
Emission characteristic testing per ISO 17560, vacuum bake-out at 250°C for 24 hours

Procurement Evaluation Criteria

A practical evidence checklist for RFQ preparation and supplier evaluation.

Technical documentation
Request current drawings, revision history, and a signed specification sheet.
Manufacturing capability
Verify equipment lists, process limits, capacity, and representative production evidence.
Inspection readiness
Confirm test methods, calibrated equipment, sampling plans, and traceable reports.
Supplier transparency
Check the legal entity, factory address, ownership, certifications, and direct contacts.

CNFX does not score or rank suppliers. Buyers must verify all claims and documents with the legal manufacturer before ordering.

Manufacturers of Cathode

Manufacturer profiles associated with Cathode.

Sourcing Cathode from China?
Tell us your specification and target quantity — we will match it against manufacturer records and come back with the factories that fit.
Request manufacturers We manufacture this

Manufacturer listings support early research and capability understanding. They are not certification, ranking, or transaction guarantees.

Related Components

Marking Ink
Specialized ink for permanent identification on surface mount resistors during manufacturing.
Dielectric Layer
Insulating layer in surface mount capacitors that stores electrical energy through polarization.
Optical Window
Transparent optical component for light transmission in polycarbonate lens housings
PCB Substrate
PCB substrate is the foundational insulating layer that provides mechanical support and electrical connectivity for electronic components in high-speed memory modules.

Frequently Asked Questions

What is the difference between thermionic and field emission cathodes?

Thermionic cathodes require heating to emit electrons, offering stable high currents but limited lifespan. Field emission cathodes use strong electric fields for cold emission, providing higher brightness and longer life but requiring ultra-high vacuum.

How does cathode material affect electron gun performance?

Material determines work function, emission efficiency, and operational stability. Low work function materials like LaB6 reduce energy consumption, while refractory metals like tungsten withstand higher temperatures but require more power.

Data Basis

Editorial classification, named public sources where available, and source-reviewed manufacturer records. See the editorial policy.

Preliminary Technical Classification
This page supports structured research, RFQ preparation, and supplier evaluation. It does not replace buyer-led supplier qualification, standards review, or technical approval.

Request Manufacturing Insight for Cathode

Thank you. Your request has been sent. We'll respond within 1–3 business days.
Sorry, we couldn't send your message. Please try again, or email us at contact@cnfx.com.
XOR Gate
Get QuotesChat