Objectives
Develop micro-engineering techniques using pulsed high brightness electron beams.
Demonstrate fine scale processing for a range of applications.
Enhance process monitoring and visualisation systems.
Project Outline
Initially, the project will adapt and implement a technology for beam pulsing that has been developed within the present non-vacuum Core Research Programme. This will enable pulsing of the diode electron gun. This system will be commissioned on the high brightness EB equipment, which also will be further developed to reduce the beam spot size to approach 1 micron diameter, and the processing will be tested for a number of industrially relevant applications.
Beam pulsing on the high brightness equipment is expected to be most useful when deployed as short duration pulses of high power, and much longer duration beam off-times between the pulses. This will allow very high power deposition in the work piece causing melting (for welding or surface texturing) or ablation (for machining) whilst the long off-time will allow the heat from the processing to diffuse, the work piece temperature to drop, and contains the processing to the minimum region eg weld fusion zones and HAZs are kept as narrow as possible. Pulsed laser beam welding and machining has taken good advantage of this technique electron beam use of this technique is anticipated to allow processing at scales 10 times smaller (eg approaching 1 micron) than laser.
The current beam current control system will be unable to control the beam peak power with the wider mark space ratio for beam pulsing than that used on NVEB. Consequently new systems will be developed to control the peak beam power.
Trials on pulsed beam processing will be conducted and comparisons made with competitive processes, in particular pulsed laser processing. Fine scale welding trials will be carried out with a focus on electronic device encapsulation applications. EB machining by ablation with pulsed beams will be investigated and the scale of features that can be machined will be determined.
Use of pulsing system to allow work piece imaging will also be investigated as it is not possible to deploy light optics to view features of 1 micron or less. This will require a method to be developed where a low power beam is generated with a smaller diameter than that used for processing, that will enable electron imaging at sufficient resolution to see the features produced by the processing.
Demonstration of this novel and unique processing equipment will be carried out focused on the emerging opportunities in the medical, electronics and sensors markets.
Relevant Industry Sectors
Electronics and Sensors, Medical, Chemical, Pharmaceutical
Technical and Economic Benefits
Power beam machining at a uniquely fine scale to enable manufacture of high value products using micro-fluidics, micro-mechanisms.
Investigation of the scale limit for the Surfi-Sculpt process.
Improved vision systems to assist high intensity EB process execution, control and QA.
License opportunities on equipment design and novel processing.
Industrial Member Report
Access the Industrial Member Reports/Bulletin Articles resulting from this programme:
High beam brightness aids fine scale processing
Fine scale processing using high beam brightness - the sequel