Heatbreak for the DICE-V2 Hotend (E3D-V6 identical in construction) made of titanium 6-5-0.5, the optimal titanium alloy for this kind of application.

Due to its strength and lower thermal conductivity, titanium is much better suited to fulfill the functions of a thermal barrier than stainless steel. E3D-Online and other heatbreak manufacturers use the world's most widely used titanium alloy for their titanium heatbreaks: Grade 5 (or also Ti-6Al-4V, EN 3.7165, UNS R56400). The Grade 5 titanium alloy has no major weaknesses, is regarded as an all-rounder and therefore accounts for more than 50% of the worldwide titanium volume.

The heatbreak offered here, on the other hand, consists of the much rarer and unfortunately also more expensive titanium alloy 6-5-0.5, which has an even lower thermal conductivity than grade 5 titanium and is even stronger. So in the two most important properties better than grade 5 titanium.

The heat flow in a heatbreak made of the titanium alloy 6-5-0.5 from Hotend (250°C) to Coldend (30°C) is therefore only about 1.78W. In relation to the stainless steel version (with about 6.37W) this is only 27.9%. This means that the coldend requires less than a third of cooling and thus reliably prevents clogging.

Furthermore, the higher yield strength makes the heatbreak more than 4 times more robust than the stainless steel version.

For comparison:

AISI 303 (EN 1.4305, UNS S30300) Stainless Steel - main alloy content: chromium, iron, nickel
Density: 7.8g/cm³ (100%) - less is better
Thermal conductivity: 15 W/mK (100%) - less is better
Yield strength: 230 MPa (100%) - more is better
Raw material price: ~1,90€/kg (8mm rod, 3m long, decrease > 30kg) (100%) - less is better
heat flow: 6,37W (100%)

Grade 5 (Ti-6Al-4V, EN 3.7165, UNS R56400) Titanium - main alloy content: vanadium
Density: 4,4g/cm³ (56,4%) - less is better
Thermal conductivity: 6.8 W/mK (45.3%) - less is better
Yield strength: 910 GPa (395.6%) - more is better
Raw material price: ~30€/kg (8mm rod, 3m long, decrease > 30kg) (1578.9%) - less is better
heat flow: 2,89W (45,4%) - less is better

Titanium 6-5-0.5 (EN 3.7155)- Main alloy content: zirconium, molybdenum
Density: 4.5g/cm³ (57.7%) - less is better
Thermal conductivity: 4.2 W/mK (28%) - less is better
Yield strength: 990 MPa (430.4%) - more is better
Raw material price: ~70€/kg (8mm rod, 3m long, decrease > 30kg) (3684,2%) - less is better
heat flow: 1.78W (27.9%) - less is better

Translated with www.DeepL.com/Translator