DRTYFN
12-31-2005, 04:44 PM
A buddy of mine works for GE and forwarded the following to me.
GE News
Appealing to consumers who want rugged, off-road capability combined with improved fuel efficiency and smaller overall dimensions, the 2006 GM HUMMER H3, a mid-size SUV, offers performance features such as the ability to climb rocks, ford streams at 20mph, and make 37-feet U-turns. To create this new vehicle, GM chose an array of high-performance materials from GE - Plastics to meet the demands of parts ranging from fenders and the roof rack to wheel covers and grille components. GE provided GM with service, design, analysis, testing, and simulation support, so that GM could ensure the quality and performance of each part.
Breaking New Ground in the Off-Road SUV Category
With the multi-year lead times required to roll out a new vehicle, collaboration on the 2006 HUMMER H3 began in 2002. Two of the most important components were the front and rear fenders. To help reduce weight and boost fuel economy, GM engineers wanted to replace these large steel parts with lighter thermoplastic, but were concerned about the demands of the fenders' wide stance, i.e., protrusion away from the vehicle body.
"GM wanted an aggressive look featuring highly defined fenders, but they required a material that would deliver design freedom combined with exceptional dimensional stability," said Tony Shackelford, Automotive Platform Manager, GE - Plastics. Dimensional stability was required to prevent gaps between the fenders and body caused by material shrinkage or expansion during extremes of cold and heat.
GM and GE worked together following which GM selected GE's Noryl GTX* 964W polyphenylene ether / polyamide (PPE/PA) resin for the fenders, based on its superior stability in heat and cold, excellent impact resistance, paintability, and design flexibility. The HUMMER H3 is the first truck-platform vehicle in North America to use thermoplastic fenders. Use of the GE material as a metal fender replacement on this vehicle significantly reduced the total vehicle weight.
Exceeding Expectations
As part of this collaboration, GE performed a thermal analysis of the fenders, as well as several other H3 parts, at its Plastics Processing and Development Center in Pittsfield, Mass. The analysis involved thermal cycling to show how the fenders would behave at high temperatures. GE's Noryl GTX resin exceeded GM's expectations for performance under demanding conditions.
Another important component was the roof rack. Originally, GM selected an ionomer from another vendor to mold this large part.
However, just six months before the vehicle rollout, the ionomer experienced processing issues. GM again turned to GE - this time, for a replacement that would provide improved processability. GE recommended Geloy* XP4034 acrylic-styrene-acrylonitrile (ASA) resin for its processing ease, as well as its weatherability without painting. The black Geloy resin is also used to mold the decorative hood louver, which requires dimensional stability and heat resistance in addition to other properties.
From a processing standpoint, GE provided an array of specialized services to support optimal tool design. At the John F. Welch Technology Center in Bangalore, India, GE process development engineers worked with GM suppliers to conduct predictive testing of the mold design using computer simulation, followed by analysis, testing, and modification of the prototype tool. After the tool went into production, GE experts continued to work with the suppliers to resolve any issues.
The other HUMMER H3 components using GE's resins are: mirror(Cycoloy* MC1300 resin); forward lighting (Lexan* 141R and LS2 resins, and Cycolac* MG38 resin); wheel covers (Noryl GTX 902 resin); front grille (Cycolac MG37EP resin); and grille opening reinforcement (Valox* 508U resin).
GE News
Appealing to consumers who want rugged, off-road capability combined with improved fuel efficiency and smaller overall dimensions, the 2006 GM HUMMER H3, a mid-size SUV, offers performance features such as the ability to climb rocks, ford streams at 20mph, and make 37-feet U-turns. To create this new vehicle, GM chose an array of high-performance materials from GE - Plastics to meet the demands of parts ranging from fenders and the roof rack to wheel covers and grille components. GE provided GM with service, design, analysis, testing, and simulation support, so that GM could ensure the quality and performance of each part.
Breaking New Ground in the Off-Road SUV Category
With the multi-year lead times required to roll out a new vehicle, collaboration on the 2006 HUMMER H3 began in 2002. Two of the most important components were the front and rear fenders. To help reduce weight and boost fuel economy, GM engineers wanted to replace these large steel parts with lighter thermoplastic, but were concerned about the demands of the fenders' wide stance, i.e., protrusion away from the vehicle body.
"GM wanted an aggressive look featuring highly defined fenders, but they required a material that would deliver design freedom combined with exceptional dimensional stability," said Tony Shackelford, Automotive Platform Manager, GE - Plastics. Dimensional stability was required to prevent gaps between the fenders and body caused by material shrinkage or expansion during extremes of cold and heat.
GM and GE worked together following which GM selected GE's Noryl GTX* 964W polyphenylene ether / polyamide (PPE/PA) resin for the fenders, based on its superior stability in heat and cold, excellent impact resistance, paintability, and design flexibility. The HUMMER H3 is the first truck-platform vehicle in North America to use thermoplastic fenders. Use of the GE material as a metal fender replacement on this vehicle significantly reduced the total vehicle weight.
Exceeding Expectations
As part of this collaboration, GE performed a thermal analysis of the fenders, as well as several other H3 parts, at its Plastics Processing and Development Center in Pittsfield, Mass. The analysis involved thermal cycling to show how the fenders would behave at high temperatures. GE's Noryl GTX resin exceeded GM's expectations for performance under demanding conditions.
Another important component was the roof rack. Originally, GM selected an ionomer from another vendor to mold this large part.
However, just six months before the vehicle rollout, the ionomer experienced processing issues. GM again turned to GE - this time, for a replacement that would provide improved processability. GE recommended Geloy* XP4034 acrylic-styrene-acrylonitrile (ASA) resin for its processing ease, as well as its weatherability without painting. The black Geloy resin is also used to mold the decorative hood louver, which requires dimensional stability and heat resistance in addition to other properties.
From a processing standpoint, GE provided an array of specialized services to support optimal tool design. At the John F. Welch Technology Center in Bangalore, India, GE process development engineers worked with GM suppliers to conduct predictive testing of the mold design using computer simulation, followed by analysis, testing, and modification of the prototype tool. After the tool went into production, GE experts continued to work with the suppliers to resolve any issues.
The other HUMMER H3 components using GE's resins are: mirror(Cycoloy* MC1300 resin); forward lighting (Lexan* 141R and LS2 resins, and Cycolac* MG38 resin); wheel covers (Noryl GTX 902 resin); front grille (Cycolac MG37EP resin); and grille opening reinforcement (Valox* 508U resin).