23rd May 2016 by Richard Yen
While we continue to look back and remember the nominees from last year’s Enlighten Award, it’s only fair that I give you a quick reminder that the deadline for this year’s award is fast approaching. In fact you have until this Friday (27th) so please let us know if you’re going to have any problems meeting that date.
Moving on, our latest nomination in review came from a joint development project between Renault and Trinseo concerning the development of a thermoplastic. This entry was an excellent case study of the potential to replace a traditionally metallic part with a lighter plastic alternative.
The companies developed a full thermoplastic lift-gate solution, which has been commercialized and implemented on the serial production of the 2015 Renault Espace. Replacing metal by plastics brings several advantages. Thermoplastics offer more design freedom and reduces upfront investments. In addition to easier recycling of this all-polymer lift-gate, it brings a 10% weight savings over a metal version. The latter contributes positively to lower fuel consumption and emissions.
It’s worth noting however that the switch from metals to plastics is not a simple case of just swapping out materials. Trinseo and Renault had to optimally utilize the material properties of the LGF-PP and TPO compounds in order to achieve the required performance attributes, while still searching for areas where material could be removed without negative impact to the design. As such, the engineering teams were required to design and engineer the lift-gate with the thermoplastic material selection in mind.
Following that, the design of the molding tooling gate location and geometry as well as the cooling system layout, ensured that the part met the necessary molding productivity levels and part quality in terms by preventing any warpage of the lift-gate.
As noted by Trinseo in their entry, replacing metal by plastics brings several advantages to car manufacturers. Thermoplastics can offer more design freedom and reduce upfront investment compared to metallic and can still be recycled. When combined with an impressive 10% saving in weight over the previous metallic version, contributing positively to lower fuel consumption and emissions, makes the material an attractive solution for car makers looking to drive down weight.