Metal-Diamond Composites

E. Neubauer

CompositionThermal Conductivity

[W/mK]CTE

[ppm/K]

Al-Dia 400 – 620 8 – 12

Cu-Dia 300 – 680 6 – 12

Ag-Dia 300 – 650 8 – 10

Task I: Optimisation of Material Composition/Processing

Table 1: Material properties realized in „lab-size“ by PM process

Task II: Optimisation of Thermal Stability of Metal-Diamond

3

0

20

40

60

80

100

120

140

160

180

200

220

240

950°C

71,1 %80,5 %

82,5 %

Cu+B+50vol.%Dia (120/140)

The

rmal

Diff

usiv

ity [m

2 /s*1

0-6]

Boron Content

heating up cooling down

0 200 400 600 800 100040

60

80

100

120

140

160

180

Cu+B+50vol.%Dia (120/140)

Th

erm

al D

iffu

sivi

ty [m

2 /s*1

0-6]

Temperature [°C]

Heating up Cooling down

4

Task III: Processing of large platesDirect heated hot pressing Expected installation of Dr. Fritsch hot press in

August/2009 Heating rate: up to 400 K/min Max. temperature: 2.400°C Size: 200mmx200mm (250mmx250mm)

Task IV: Uniformity of Material Properties on large plates

Local Thermal Analyses of Al-diamond composites

Al-Diamond system is very sensitive to T-t in processing

Al-Diamond composite 270 +/- 20 mm²/s 500 – 600 W/mK

6

Task V: Shaping/Surface Finishing

Good surface quality can be realised by: preparation of sandwich structures or bi-layer structures

“Machining/Cutting” of composites is possible by:

Water Jet Cutting Laser Cutting Electro Discharge Machining