Tungsten plates on the market in 2010

( Plansee – Cime Bocuze )

• Pure W – W Composite• Production Process• Available Products• Mechanical and Magnetic Properties• Preliminary Ideas for a Prototype

W. Klempt CERN/PH CLIC physics/detector meeting 17 June 2009

W – W Composite Material

• Pure W is difficult to use:– pretty brittle– Difficult to machine

• W composite materials:– Consist of W (≥ 90%) rest mixture of Fe, Ni, Cu … = 17 – 19 g/cm3

– Λ ≈ 10 cm, X0 ≈ 0.4 cm– Well established production procedure– Easy to machine– Price ~ 70 Euro/kg

Production Process of Tungsten Composite Materials

Product Range and Material Properties

Mechanical Properties

Magnetic properties of Densimet 180

Tungsten+Nickel :: Permeability vs B

0

10

20

30

40

50

60

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14

B [T]

Per

mea

bilit

y

tungsten

Magnetic properties of Densimet 180

Tungsten B vs H

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0 5000 10000 15000 20000 25000 30000

H (A/m)

B (T

esla

)

Desimet 180 mu = 1μ

Maximum size

• Maximum size is given by size of the oven

• Today a reasonable maximum size is about 1 ton of product.

• In case of 10 – mm - thick plates the maximum size is about 500 mm x 800 mm after cutting and machining.

• Rolling is complicate: hard phase (tungsten) mixed with ductile phase (CuNi). Brittleness increases!

A promising technique - extrusion

• Powder is mixed with a polyimide (nylon or similar).• The mixture is extruded.• First pre-sintering process (~800 oC).• Final sintering.• Option – rolling to straighten the plates – not to change thickness.

Size: from 0.5 to 5 mm thicknessnow 200 mm x 600 mm (could be longer).

Good mechanical properties but tried only with Densimet (NiFe).Next step: try it with Inermet (CuNi).

Very preliminary ideas on a possible prototype

Veto

Calorimeter

Beam

MC calculations correct for W ? (invisible energy, neutrons)

Depth ?Width ?Sampling rate, fraction?

Shower Geometry (W 10mm, gap 8mm)Calculations done by C. Grefe

r [m

m]

E [GeV]

Dep

th [m

m]

r

L

D

Leng

th [m

m]

E [GeV]

E [GeV]

Very preliminary ideas on a prototype

20

12

~5

~30

~480

ADP or SiPM

Scintillatortile

W plate

Start with a small size but build in an extendable wayProduction techniques for a later calorimeter should be used

Wavelengthshifter

Depthlayers

Width[mm]

No of channels

W weight [kg]

30 (3.4 Λ) 390 5070 1000

40 (4.6 Λ) 480 10240 2000

50 (5.7 Λ) 480 12800 2500

Conclusions

• Non brittle Tungsten (alloy, W≥90%) plates are available • Mechanical properties ok, magnetic properties to be

verified• Size today somehow small (< 0.3 m2), but can be

developed• Envisage construction of a small but extandable

prototype?