<p>I’ll add from my experience: for printing with composite materials, when using a tungsten carbide nozzle, if screwed into an aluminum hotblock (even when screwed hot), the nozzle quickly unwinds and then plastic leaks. In the case of a copper hotblock, a similar effect is not observed (apparently, this is explained by different thermal expansion of the materials).</p>

CC BY-SA 4.0
2024-01-24T10:30:58.973Z
Thermal expansion coefficient in [m/m∙K]: Copper 17∙10E-6. Aluminium 23∙10E-6, Tungsten Carbide: 5.5∙10E-6 - the copper block does not "swell" as much as the aluminium one, the tungsten carbide is only 1/3rd and 1/5th of the expansion comparatively - it should get *squeezed* in by both during a heat cycle... copper has much lower friction though.
Trish
CC BY-SA 4.0
2024-01-24T08:58:26.800Z
2024-01-24T08:58:26.800Z
liga consul
<p>The choice depends on the application you have in mind, but basically you can look at the properties of copper and aluminium to find out what may be better for your application.</p>
<ul>
<li>Dynamics
<ul>
<li>Copper is about 3 times heavier, this potentially increases the weigth of the hot end and as such increases the change to have more issues with e.g. ringing for a similar sized heater blocks</li>
</ul>
</li>
<li>Thermodynamics
<ul>
<li>Maximum temperature can be higher for copper, the melting temperature is almost twice the value for aluminium (in printing in excess of 320 °C you want to use a copper heater block)<sup><em>1)</em></sup></li>
<li>Heat conductivity for copper is almost twice the value of that of aluminium, it conducts heat much better, so the block is more evenly heated.</li>
<li>Heat capacity of copper is almsot half of that of aluminium, so it requires more energy to heat up the same amount of mass. Specific heat or heat capacity of aluminum is  0.90 J/(g °C); for copper it is 0.385 J/(g °C). To heat up the  same amount of mass you'll need a little over twice the amount of energy, or with a given influx it will take more time. As we can assume the volume of the heatblocks is the same, the mass of the copper block will be higher and therefore will take even more time to heat up.</li>
</ul>
</li>
</ul>
<p>Copper can be nickel coated/plated, this creates a surface that is less prone for filament to get stuck on and is more easy to cleam with isopropanol alcohol.</p>
<p>A copper heater block may help keep temperatures more stable, but this is already done by the printer controller board (PID tuning). Generally, it will not help with a higher flow rate, since plastic thermal conductivity is the limiting factor here, not the heater block. For increased flow application you should go to a (Super)Volcano heater block; for a smaller volumetric flow increase one could use e.g. CHT style nozzles (effectively increased the filament contact area with the nozzle/heater block.</p>
<p>Basically, using a copper heater block is advised when printing at high temperatures (&gt; 320 °) for prolonged times.</p>
<hr />
<p><em><sup>1)</sup> Aluminum heater blocks begin to degrade above 350 °C, while a copper alloy doesn't even begin to soften until way beyond 500 °C</em></p>

CC BY-SA 4.0
2023-11-29T15:05:30.573Z
Good answer. My printer is a slow one, so mechanical issue is not an issue - for me. Good to know none the less. I don't think I observe any issues that would require me to upgrade to copper. I have a small amounts of PC and ASA I need to print for projects, but for the most part I'll stay with PLA and PETG. Aluminum in silocone socket should be more than sufficient.
Mołot
CC BY-SA 4.0
2023-11-29T15:43:07.410Z
PS could copper block offset worse thermal transfer of a steel or titanium nozzle?
Mołot
CC BY-SA 4.0
2023-11-29T16:03:53.370Z
@Mołot The thermal conductivity of pure titanium is 17 W/(mK), about a quart of iron and about 1/23 of copper. Titanium is easy to warm and easy to cool. It's strange that it is easy to warm though the heat conduction is bad. The heat capacity is about the same for Ti and steel. A nice video I just found on using more copper in the hotend: https://www.youtube.com/watch?v=IjUXhg7Waqo
0scar
CC BY-SA 4.0
2023-12-02T22:29:25.750Z
Just to put last dot - I swapped for the plated copper **and** high-flow CHT style nozzle and my ASA prints are finally succeeding. Nozzle itself wasn't quite enough, my print crumbled after about 10 layers as if some filament was extruded too cold.
Mołot
CC BY-SA 4.0
2024-01-24T10:25:59.340Z
I would compare copper to aluminium as 4/9th, not 5/10th, but close enough. ;)
Trish
CC BY-SA 4.0
2023-11-29T14:50:12.857Z
2023-11-29T14:50:12.857Z
0scar
<p>Just as the title says - I'm in the need of a new heater block, and need to decide which one to buy. Plated copper is 10 times more expensive now, at least where I live (70 PLN <em>which is about 16 Euro or 18 USD</em> vs 7 PLN for aluminum), but in the scale of the cost of a printer, difference is negligible.</p>
<p>Copper has better thermal transfer, but it also has a greater thermal mass, so it heats up and cools down slower, but should be able to melt plastic faster. Or so it seems. I don't know how these theoretical properties translate into practical pros and cons for 3D printing.</p>
<p>I'm not looking for &quot;buy this&quot; answer. I'm looking for comparison that will let me, and future readers, make informed decision.</p>

<heat-management><replacement-parts>
What are the differences between aluminum and copper heater block and why would I use one vs another?
Mołot
# What are the differences between aluminum and copper heater block and why would I use one vs another?

(Asked by: username_0 on 2023-11-29)

Just as the title says - I'm in the need of a new heater block, and need to decide which one to buy. Plated copper is 10 times more expensive now, at least where I live (70 PLN *which is about 16 Euro or 18 USD* vs 7 PLN for aluminum), but in the scale of the cost of a printer, difference is negligible.

Copper has better thermal transfer, but it also has a greater thermal mass, so it heats up and cools down slower, but should be able to melt plastic faster. Or so it seems. I don't know how these theoretical properties translate into practical pros and cons for 3D printing.

I'm not looking for "buy this" answer. I'm looking for comparison that will let me, and future readers, make informed decision.

**Tags:** heat-management, replacement-parts

---

## 2 answers

### Answer by username_3 on 2023-11-29. Score: 4 | Accepted answer

The choice depends on the application you have in mind, but basically you can look at the properties of copper and aluminium to find out what may be better for your application.

* Dynamics
  + Copper is about 3 times heavier, this potentially increases the weigth of the hot end and as such increases the change to have more issues with e.g. ringing for a similar sized heater blocks
* Thermodynamics
  + Maximum temperature can be higher for copper, the melting temperature is almost twice the value for aluminium (in printing in excess of 320 °C you want to use a copper heater block)*1)*
  + Heat conductivity for copper is almost twice the value of that of aluminium, it conducts heat much better, so the block is more evenly heated.
  + Heat capacity of copper is almsot half of that of aluminium, so it requires more energy to heat up the same amount of mass. Specific heat or heat capacity of aluminum is 0.90 J/(g °C); for copper it is 0.385 J/(g °C). To heat up the same amount of mass you'll need a little over twice the amount of energy, or with a given influx it will take more time. As we can assume the volume of the heatblocks is the same, the mass of the copper block will be higher and therefore will take even more time to heat up.

Copper can be nickel coated/plated, this creates a surface that is less prone for filament to get stuck on and is more easy to cleam with isopropanol alcohol.

A copper heater block may help keep temperatures more stable, but this is already done by the printer controller board (PID tuning). Generally, it will not help with a higher flow rate, since plastic thermal conductivity is the limiting factor here, not the heater block. For increased flow application you should go to a (Super)Volcano heater block; for a smaller volumetric flow increase one could use e.g. CHT style nozzles (effectively increased the filament contact area with the nozzle/heater block.

Basically, using a copper heater block is advised when printing at high temperatures (> 320 °) for prolonged times.

---

*1) Aluminum heater blocks begin to degrade above 350 °C, while a copper alloy doesn't even begin to soften until way beyond 500 °C*

> **Comments:**
> **username_0**: Good answer. My printer is a slow one, so mechanical issue is not an issue - for me. Good to know none the less. I don't think I observe any issues that would require me to upgrade to copper. I have a small amounts of PC and ASA I need to print for projects, but for the most part I'll stay with PLA and PETG. Aluminum in silocone socket should be more than sufficient.  
> **username_0**: PS could copper block offset worse thermal transfer of a steel or titanium nozzle?  
> **username_3**: @Mołot The thermal conductivity of pure titanium is 17 W/(mK), about a quart of iron and about 1/23 of copper. Titanium is easy to warm and easy to cool. It's strange that it is easy to warm though the heat conduction is bad. The heat capacity is about the same for Ti and steel. A nice video I just found on using more copper in the hotend: https://www.youtube.com/watch?v=IjUXhg7Waqo  
> **username_0**: Just to put last dot - I swapped for the plated copper **and** high-flow CHT style nozzle and my ASA prints are finally succeeding. Nozzle itself wasn't quite enough, my print crumbled after about 10 layers as if some filament was extruded too cold.  
> **username_2**: I would compare copper to aluminium as 4/9th, not 5/10th, but close enough. ;)  

---

### Answer by username_1 on 2024-01-24. Score: 1

I’ll add from my experience: for printing with composite materials, when using a tungsten carbide nozzle, if screwed into an aluminum hotblock (even when screwed hot), the nozzle quickly unwinds and then plastic leaks. In the case of a copper hotblock, a similar effect is not observed (apparently, this is explained by different thermal expansion of the materials).

> **Comments:**
> **username_2**: Thermal expansion coefficient in [m/m∙K]: Copper 17∙10E-6. Aluminium 23∙10E-6, Tungsten Carbide: 5.5∙10E-6 - the copper block does not "swell" as much as the aluminium one, the tungsten carbide is only 1/3rd and 1/5th of the expansion comparatively - it should get *squeezed* in by both during a heat cycle... copper has much lower friction though.  

---

