Die Cast Heat Sink

Die cast heat sink is more cost effective for high production volume products. However, porosity may affect heat transfer and result in inconstant thermal performance. We will recommend die cast heat sink to our clients in 2 scenario:
1) application with very high production volume with relatively high thermal design margin
2) very complex shape that is not being able to be produced by extrusion with cost effectiveness. (round shape with a lot of machining by extrusion, LED application)
3) heat sink also served as a casing which is not the main media to dissipate heat from the heat source directly.
Material: A380, ADC12