Tungsten Copper "CuW" and "WCu" redirect here. For other uses, see CuW (disambiguation) and WCu (disambiguation). Copper-tungsten (tungsten-copper, CuW, or WCu) alloy is a pseudo-alloy of copper and tungsten. As copper and tungsten are not mutually soluble, the material is composed of distinct particles of one metal dispersed in a matrix of the other one. The microstructure is therefore rather a metal matrix composite instead of a true alloy. The material combines the properties of both metals, resulting in a material that is heat-resistant, ablation-resistant, highly thermally and electrically conductive, and easy to machine. Parts are made from the CuW alloy by pressing the tungsten particles into a desired shape, sintering the compacted part, then infiltrating with molten copper. Sheets, rods and bars of the alloy are available as well. Commonly used copper tungsten alloy contains 10 to 50 wt. % of copper, the remaining portion being mostly tungsten. The typical properties of the alloy depend on its composition. The alloy with less wt.% of copper has higher density, higher hardness and higher resistivity. The typical density of CuW90 alloy, with 10% of copper, is 16.75g/cm3 and 11.85g/cm3 for CuW50 alloy. CuW90 has higher hardness and resistivity of 260 HB kgf/mm2 and 6.5 ?Ω.cm than CuW50. Material Composition (%) Hardness (HRB) Electrical Condutivity (%IACS) UTS (PSI) Density (g/cm?) Thermal Conductivity w/cm°c ( 20°c) 10CI W=90 Cu= Bal. 103-109 26-35 - 17,05 1,45 20CI W= 80 Cu= Bal. 98-106 38-45 96000 15,50 1,50 30CI W= 70 Cu= Bal. 92-96 44-52 85000 14,20 1,75 40CI W= 60 Cu=Bal. 70-85 47-57 - 13,00 1,95 50CI W= 50 Cu= Bal. 65-75 51-65 - 12,00 2,00 50WCI Wc= 50 Cu= Bal. 91-97 44-50 70000 11,30 - Molybdenum – Copper alloys Molybdenum – copper alloys produced by powder mettalurgy have low density and excellent thermal conductivity . They are used in vacuum switchgears , heat sinks and other electrical and engineering applications . Material Composition (%) Hardness HB 2.5 / 62.5 Electrical Condutivity (%IACS) UTS (PSI) Density (g/cm?) Thermal Conductivity w/cm°c 35MCI Mo= 65 Cu= Bal. 125-145 45 minimum 40590 9,70 minimum 1,65 20MCI Mo= 80 Cu= Bal. 135-155 35 minimum 43480 9,95 minimum 1,45