This V6 heat break consists of 3 parts:
Upper part made of copper to make the cooling effective as possible.
Middle part made of aerospace ceramics for the best thermal insulation between the upper and lower part.
Lower part made of copper for the best heat transfer over the heat block.
Copper + aerospace material heat break:
Copper: 380 W/m*K
Ceramics (ZnO2): 2-5 W/m*K (2 W/m*K– ZnO2)
Other heat break types:
Stainless steel: 16-24 W/m*K
Titanium alloy: 5-7 W/m*K
This is how a cross-section of a V6 hot end with a copper-aerospace material heatbreak looks like (without the heatsink).
As you can see in the comparison below, the weight is:
Commer + aerospace material heat break: 3.05 g
Standard all metal heat break: 3.32 g
Titanium heat break: 1.85 g