It has been 25 years since the commercial breakthrough for plastics being used instead of steel in car fenders (wings). The 1987 Buick LeSabre T-Type 1 from General Motors in the US was the first high volume production car to have on-line painted plastic fenders, which were injection moulded in Noryl GTX resin from GE Plastics.
Since then, other major automotive companies have made fenders from the resin. Even so, Sabic Innovative Plastics, the successor to GE Plastics, is still able to announce new milestones.
The materials company has developed a post-industrial recycled (PIR) grade of Noryl GTX which Renault is using for the fenders of its 2013 Clio IV model. It will also use the PIR grade in its Zoe electric vehicle.
The adoption of Noryl GTX PIR grade forms part of Renault’s ICARRE 95 (standing for Innovative CAR REcycling +95%) project to meet the EU’s end-of-life vehicle (ELV) requirements. Renault is targeting a 95% recovery rate for ELV materials.
Noryl GTX materials are a blend of polyamide (PA) and modified polyphenylene ether polymer (PPE). The high heat resistance of PPE means they are able to withstand the temperatures used in automotive paint lines. The materials also show strong chemical and impact resistance.
The new PIR grade, which is sourced from body panels, meets the required automotive quality and performance standards, says Sabic.
In another new development, the Noryl GTX 989 grade is the material used by Mitsubishi for the front fender of its 2013 Outlander Sport crossover. The two parts of the vehicle’s fender are moulded in a two-cavity mould, the first to be produced using two-cavity injection moulding with Noryl GTX resin, says Sabic.
Both the left and right fender components of the Outlander Sport are produced in one shot, which reduces the cycle time and cuts costs because only one tool is made instead of two.
The 989 grade was recently developed to deliver a 10°C improvement in heat tolerance compared to the previous grade, making it suitable for higher-temperature online painting. Sabic says: “The next-generation Noryl GTX 98X series materials also reduce the coefficient of linear thermal expansion by 10% versus previous grades for increased dimensional stability and improved gap and flush management, giving automotive designers freedom to create larger, high-precision body panels.”
Mitsubishi took advantage of this enhanced design freedom to integrate energy-absorbing brackets into the fender to improve pedestrian protection. Sabic says validation studies indicated a head injury criterion (HIC) value for the Noryl GTX resin fender that was 25% lower than a comparable steel fender.
The new Outlander Sport plastic fender reduced vehicle weight by 3kg. This weight reduction is particularly important in view of the recently announced US fuel economy rules, which essentially double the mileage requirement for OEM fleets.
Another first was claimed by Sabic last year when Mahindra & Mahindra became the first Indian automotive manufacturer, with support from its Tier 1 supplier Plastic Omnium, to have a plastic fender. Noryl GTX is used for the fender of the car company’s XUV500 sports utility vehicle, making it one of the lightest SUVs in its class.