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/cm 3 –Λ ≈ 10 cm, X 0 ≈ 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

μ

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 o C). Final sintering. Option – rolling to straighten the plates – not to change thickness. Size: from 0.5 to 5 mm thickness now 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 [mm] E [GeV] Depth [mm] r L D Length [mm] E [GeV]

Very preliminary ideas on a prototype ~5 ~30 ~480 ADP or SiPM Scintillator tile W plate Start with a small size but build in an extendable way Production techniques for a later calorimeter should be used Wavelength shifter Depth layers Width [mm] No of channels W weight [kg] 30 (3.4 Λ) (4.6 Λ) (5.7 Λ)

Conclusions Non brittle Tungsten (alloy, W≥90%) plates are available Mechanical properties ok, magnetic properties to be verified Size today somehow small (< 0.3 m 2 ), but can be developed Envisage construction of a small but extandable prototype?