Aluminium HTA: the new alloy for high temperature applications

Aluminium HTA – High Temperature Aluminium – is the new material developed by the Zare Research and Development Centre with the aim of ensuring high performance even at high temperatures. Aluminium HTA is part of the Aluminium-Copper system and maintains its distinctive excellent mechanical properties even at temperatures of 190—200°C..

Aluminium HTA is a new material that Zare has developed and parameterised in the company's Research and Development Centre, taking advantage of the experience gained in additive processes. The material is part of the Aluminium-Copper system, unlike aluminium alloys traditionally used in additive processes (e.g. AlSi10 and AlSi7), or in castings, which are part of the Aluminium-Silicon system.

Aluminium HTA has been developed specifically for high temperature applications, with the aim of combining the mechanical performance of aluminium alloys used with the traditional method with the advantages of additive technology.
It withstands temperatures up to 200°C without any deterioration in the physical and mechanical properties, thus guaranteeing consistent results and reliability.

Aluminium HTA: the new aluminium alloy for high temperature applications

Why and when to choose the Aluminium HTA alloy

The excellent mechanical properties at high temperature are without question the distinguishing aspect of Aluminium HTA, to which are added other important features:

  • the material maintains its mechanical properties even if subjected to continuous high temperatures for a long time and shows only a slight deterioration under more extreme situations;
  • it can also be used at temperatures of 190-200°C, unlike the more classic AlSi10 and AlSi7 which, instead, can only withstand temperatures between 100-150°C;
  • the yield strength and the ultimate tensile strength that characterise Aluminium HTA, especially when compared to AlSi10 and AlSi7, make it possible to create lighter components since, given the material's excellent properties, it is possible to reduce the resistant sections.

Therefore, Aluminium HTA stands out for its ability to keep its qualities unchanged even at extremely high temperatures, especially when compared to traditional alloys, such as AlSi10 and AlSi7, but also to alloys with higher performance such as Scalmalloy.
Aluminium HTA also has mechanical properties similar to those of alloy 2618 traditionally used in mechanical machining, both at room temperature and at high temperature.

Aluminium HTA: the new aluminium alloy for high temperature applications

Uses and sectors of application of the Aluminium HTA alloy

Aluminium HTA can be used in all applications where the lightness of the components must be combined with resistance to high temperatures, therefore there are many sectors where it can be used.

Motorsport, aerospace and automotive are just some of the industries that can benefit most from the advantages offered by the material and additive manufacturing since, for these sectors, there are already numerous case studies that can be utilised in additive manufacturing.

Aluminium HTA lends itself to the production of small batches of finished functional pieces especially in engine manufacturing, examples of applications in this field are cylinder heads, cylinders, pistons and turbocharger turbines. Even hydraulics can appreciate the characteristics of the material in all those applications where temperatures continually exceed 100-120°C.

Aluminium HTA: the new aluminium alloy for high temperature applications

Additive Manufacturing with Aluminium HTA: the advantages for the designer

The possibility of using an aluminium resistant to high temperatures with additive technologies, where other types of aluminium tend to fall back in terms of mechanical performance, opens up new possibilities for mechanical designers in highly complex sectors and activities; the use of Aluminium HTA makes it possible to maintain the functionality of the component by varying and exploiting the technological advantages, especially on the design side, that the additive production can offer.

Even on-demand productions, which often encounter difficulties with stocking the raw material, can find benefits in the new Aluminium HTA alloy.
The combined use of Aluminium HTA and additive technology, with its noted versatility and speed, makes it possible to tackle and resolve the complexities associated with on-demand production and, more generally, those typical of sectors that require a more extreme performance.

Choosing additive manufacturing, above all for use with materials with high mechanical characteristics such as Aluminium HTA just developed by the Zare Research and Development Centre, allows designers to design with once unimaginable freedom, creating even more extreme shapes and reducing the mechanical machining. The supply chain is shortened as well as the time required to obtain the functional and final product.

Aluminium HTA: the new aluminium alloy for high temperature applications

More specifically, the advantages for the designer in the use of Aluminium HTA for additive production are:

  • the superior mechanical properties both at room temperature and at high temperature;
  • the complete freedom that the material offers for geometries, complex shapes and thicknesses in designing the product. It is common knowledge, for example, that castings of the Aluminium-Copper system have lower limits for the thicknesses of the walls which force to design taking into account a minimum thickness of at least 2 millimetres. However, thanks to additive technology, we can go further, up to obtaining ultra-thin thicknesses, even 1/1.5 millimetres.
  • The lightness of the products: the very thin wall thickness mentioned above, combined with the excellent mechanical properties that remain unchanged even at high temperatures, allows for a much lighter finished product.

Aluminium HTA: the new aluminium alloy for high temperature applications

An example of application using additive technologies and Aluminium HTA

An example of Aluminium HTA application is the manufacturing of cylinder heads.
As a rule, cylinder heads are cast using AlSi7, a material which, at high operating temperatures (over 150°C), experiences a deterioration in mechanical properties: the designer must therefore in this context design significant thicknesses to counteract the effects of such deterioration.

Aluminium HTA can be effectively utilised for cylinder heads since, compared to the other alloys usually used, the properties remain substantially unchanged up to temperatures of 200°C, the product can therefore have much thinner sections and a higher operating temperature while still being reliable.