1. Material Irradiation Tests June 2016 coordination meeting
Part I : Objectives & Context
Elisa Guillermain

2. Aims and Goals of the meeting
Provide information for irradiation test of materials preparation and workflow
Overview of current possibilities in terms of irradiation conditions and irradiation facilities
Rise awareness on the need for reporting and archive
Gather foreseen irradiation tests of materials for the next 3 / 4 years
Coordination : Technical, contractual
Strong encouragement to the equipment groups to get in touch for the foreseen tests for best coordination

3. Part I Outline Radiation damage Purpose of irradiation tests
Previous irradiation tests of materials for CERN
Present situation
Role of the support team
Other support structures
The Rad WG
The MC WG

4. Radiation damage

5. Radiation damage Radiation
Emission or transmission of energy in the form of
electromagnetic waves or particles
Single Event
Effects
SEE
Displacement
Damage DD
Ionization
Total Ionizing Dose
TID
Stochastic damage
to electronics… Not today’s topic !
Cumulative effects
Defects accumulation of over a certain period

6. Structural Effects on Materials
Radiation damage
Structural Effects on Materials
Polymer
Radiolysis
Chain rupture
Recombination
Semiconductors
Lattice displacement
Metals
Lattice displacements
Voids, bubbles, clusters
Glass
Color centers,
Lattice displacement
Liquids
Radiolysis
Ceramics
Lattice displacements,
Color centers

7. Radiation damage Consequence on materials
Mechanical issues
Strength, ductility, toughness modifications
Cracks can appear
Optical issues
Loss of transmission
Change of refractive Index
Electrical issues
Insulation properties
Devices electrical properties modified
Consequences on systems and equipment
Damage to the material of a defined system might alter its functioning !

8. Purpose of Irradiation tests of materials

9. Purpose of irradiation tests of materials
Assessing material radiation damage
Estimate its lifetime at a specific position
Ensure the RELIABILITY of installed equipment
Reduce machine downtime
Respect ALARA principles
Save time and money
ʺUltimately Radiation Hardness Assurance (RHA) guidelines shall be added to ECR (Engineering Change Request), and irradiation tests are fully parts of this quality assurance processʺ.
R2E, Chamonix January 2016, S. Danzeca

10. Purpose of irradiation tests of materials
Radiation resistance often depends on exact composition of material
Can be decades of difference in same material families
Aim is to chose the best resistant among available possibilities
‘’The sensitivity to radiation is often very variable and it is therefore impossible to use theory alone to predict the effect on a device of a given exposure to radiation. Actual irradiation tests must therefore be an integral part of the evaluation of the parts of a system and, sometimes, tests must be performed on each batch of parts’’
Handbook of radiation effects, 2nd edition, Andrew Holmes-Siedle & Len Adams
Irradiation tests can be performed in the frame of:
Qualification tests – choice of best material
Quality control tests – batch testing
Extensive test campaign

11. Available data

12. Available data: Yellow books
Compilation of radiation damage test data
Test data from 1979 up to 2001
9 reports concerning various materials
More than 200 materials tested
Irradiation tests conditions
60Co, ≈1 Gy/s, 200 kGy up to few MGy
Nuclear reactor , ≈50 Gy/s, up to 100 MGy
Marc Tavlet, H. Schönbacher, A. Stolarz-lzycka, P. Beynel, P. Maier, B. Szeless, A. Fontaine, F. Guarino, C. Hauviller
Give guidelines on material behavior

13. Available data : Yellow books
100 MGy
100 kGy
5 MGy
Extensive tests
Great quality
Still the main reference for CERN users
Yellow book CERN-98-01
Compilation of radiation damage test data, pt.2, Table 2

14. Available data Other databases, often electronics in space environment
NASA (
ESA (
CERN expertise is often demanded for harsher environments
Always the need for CERN to perform its own test on materials

15. Present situation

16. Present situation - Radiation conditions
Recent past
In the LHC
Higher beam energy (was initially 3.5 TeV, now 6.5 TeV per beam, foreseen 7 TeV)
25 ns operation (was 50 ns), now higher beam gas interactions
Ion runs has high impact on TID
In the injector chain
Slides from Joao De Carvalho Saraiva
Situation is often worst in some injectors / some areas rather than in LHC !

17. Present situation - Radiation conditions
BLM data, extrapolated for HL-LHC
(luminosity increase led to radiation levels increase)
© Corinna Martinella

18. Present situation - Radiation conditions
Future upgrades
HL-LHC (2020)
Luminosity is expected to increase by a factor of 10 beyond the original design value (from 300 to 3000 fb-1)
Increase of luminosity will increase total doses in the LHC
Expected radiation level for 2017 are ~4x higher than 2015
Long-term : FCC studies
Increasing accumulated doses in the accelerators:
Not only electronics will suffer form radiation
In some position, will become critical for some material, some parts, some components.

19. Present situation – Irradiation tests

20. Role of the support team

21. Role of the support team
Tests concerned
Passive test on material or systems and tests at high doses
Often outsourced / sub contracted, but sometimes CERN in- house facilities
Support
To equipment groups and to service groups for assessing the radiation resistance of equipment to be installed in harsh environment.
Irradiation tests preparation
Administrative support
Offer, order, confirmation, invoicing
Documentation
Profit from previous experience !

22. Role of the support team
Coordination
Irradiation test follow up
Planning and Scheduling (start / end)
According to equipment group requirements
Communication
Reduce the number of interlocutors with external irradiation facilities
Centralize the collaboration with external facilities (administrative, contractual)
Contractual aspects
Mutualisation allows for tests combination and setting-up of frame contracts
Save money and time…
Clear overview of future tests for ensuring appropriate contracts !
Gathering of new requests at the end of the meeting.

23. Support structures The Rad WG Chairman : Salvatore Danzeca The MC WG
Chairman : Yacine Kadi