# Presentation: 649833

## PLANMATERIAL STUDIES FOR PULSED HIGH-INTENSITY PROTON BEAM TARGETS 

**Nicholas Simos, Harold Kirk, **
**Hans Ludewig, Peter Thieberger, **
**Leonard Mausner, W-T Weng **
**BNL**
**Kirk McDonald, Princeton U**
**Y. Hayato, K. Yoshimura**, KEK
**J. Shepard, SLAC**

## SOLUTION: 

**AS WE GET TO 1+ MW SYSTEM**
- Heat generation and removal from the target system
- Target thermo-mechanical response from energetic, high intensity protons
- Irradiation and corrosion effects on materials
- Beam window survivability

**SOLUTION:**** **
- Look for new materials that are continuously being developed
- for other applications but seem to fit the bill as targets

**There is a catch !**
- These materials have not been tested for their resilience
- to radiation exposure

## The collaboration has been looking into these materials 

- The collaboration has been looking into these materials
- for some time
- Candidate materials studied for applications as targets
- windows are:
- Inconel-718
- Aluminum-3000
- Havar
- Ti-6Al-6V
- Graphite (ATJ)
- Carbon-Carbon
- SuperInvar

## PHASE I:  Graphite & Carbon-Carbon Targets 

## E951 Results: ATJ Graphite vs. Carbon-Carbon CompositeThe results demonstrate the superiority of CC in responding to Beam SHOCK.The question is: Will it maintain this key feature under irradiation ???We will find out in the course of this irradiation phase

**E951 Results: ****ATJ Graphite vs. Carbon-Carbon Composite****The results demonstrate the superiority of CC in responding to Beam SHOCK.****The question is: Will it maintain this key feature under irradiation ???****We will find out in the course of this irradiation phase**

## Irradiation Studies to Assess how Super-Invar responds to radiation.

**Irradiation Studies to Assess how Super-Invar responds to radiation.**
**Its key feature (low CTE up to 150 ****o****C) needed to be scrutinized**

- Specimens and dilatometer in hot cell

## BNL Irradiation Studies

**BNL Irradiation Studies**
**Super Invar & Inconel-718**

**Inconel-718 rods**

## Slide 8

## Super-Invar Irradiation Study – CTE assessment

- Super-Invar

## Inconel-718  CTE assessment

## Super-Invar Irradiation Study - 

- Effects of Irradiation on stress-strain behavior

**WHY STUDY super Invar ?**
**High-Z with low CTE (0-150 ****o****C)**
**How is CTE affected by radiation?**
**What happens to other important properties?**

- While the dpa received where as high as .25,  they were enough to capture the tendency of the material to change. Similar effects at such low dpa can be seen in Inconel (Figure below)

## Super-Invar Irradiation Study - Irradiation vs. Yield Strength

- Effect of irradiation on yield strength
- of SuperInvar

## Super-Invar Irradiation Study – Temperature Effects

## Super-Invar Irradiation Study 

- Stress-strain (load-displacement) in stainless steel samples to
- test system stability

## PHASE-II TARGET MATERIAL STUDY 

**WHAT’S NEXT ?  **Repeat irradiation/mechanical property changes experiment for baseline materials

_**Carbon-Carbon composite**_
-              This low-Z composite gives the indication that it can minimize the thermal shock and  survive high intensity pulses.
-              Because of its premise it is the baseline target material for the BNL neutrino superbeam initiative.
-              The way its key properties (such as CTE or strength) degrade with radiation is unknown.
_**Titanium Ti-6Al-4V alloy**_
- The evaluation of the fracture toughness changes due to irradiation is of interest regarding this alloy
- that combines good tensile strength and relatively low CTE
-         _**Toyota “Gum Metal”**_
-                   This alloy with the ultra-low elastic modulus, high strength , super-elastic like nature and near-zero linear expansion
-                   coefficient for the temperature range -200 oC to +250 oC to be assessed for irradiation effects on these properties.
_**VASCOMAX**_
-                   This very high strength alloy that can serve as high-Z target to be evaluated for effects of irradiation on CTE,
-                   fracture toughness and ductility loss
-           _**AlBeMet**_
-               A low-Z composite that combines good properties of Be and Al. Effects of irradiation on CTE and mechanical
-               properties    need to be assessed
**IG-43 Graphite**

## PHASE-II TARGET MATERIAL STUDY 

**WHAT’S DIFFERENT FROM PHASE-I?**
- ~ **100 MeV of Proton Beam (200 to 100 MeV)**
**Challenge of inducing UNIFORM Beam degradation**
**MORE Material to go in (optimization of dE/dx for range 200 MeV-100 MeV)**
**OPEN Issue:  Study of Fracture Toughness for some materials ?**

## Carbon-Carbon Composite Target

## Gum Metal (Toyota Ti alloy)

## Slide 19

## Slide 20

## Slide 21

## Tensile & CTE Specimen Design for Upcoming Irradiation Study

## Tensile & CTE Specimen Design for Upcoming Irradiation Study

- Vascomax-350 specimen variation due to its high strength

## Tensile & CTE Specimen Design for 

- Carbon-Carbon and IG-43 Graphite

## LAYOUT OF Specimen Assembly

## Tentative Sample Identification Scheme