Development of Additional SAE J2643 Standard Reference Elastomers Nancy Zeng General Motors Company Randy L. Dickerman Chrysler Group LLC ABSTRACT The first set of SAE J2643 Standard Reference Elastomers (SRE) was developed in 2004. It was composed of a group of 10 compounds covering multiple elastomer families. Since then, more advanced materials from many elastomer families have been introduced to the automotive industry. The purpose of this study is to add a few more reference compounds to SAE J2643, to enhance the portfolio on FKM, AEM and ACM to reflect advancements in elastomer technology, and make it suitable for a variety of fluids, such as transmission fluid and engine oil. Fourteen standard elastomer compounds were involved in this study, covering various materials currently used in automotive powertrain static and dynamic sealing applications. Participants include OEMs, major rubber manufacturers, a fluid additive company and an independent lab. Manufacturers of each test compound provided formulations, designated ingredients from defined sources, and detailed mixing and molding procedures. All fourteen compounds were molded at Akron Rubber Development Lab (ARDL), the only approved mixing facility for SAE J2643 SRE compounds. Testing specimens were also die-cut by ARDL to minimize sample preparation variation. Two fluids were utilized for the study: ASTM SF105 fluid and GM DEXRON®-VI automatic transmission fluid (ATF). Elastomer specimens were aged in the designated fluids per ASTM D471. This paper only reports test results for the ASTM SF105 fluid. The DEXRON®-VI results will be reported internally within GM.INTRODUCTION Ethylene acrylic copolymer (AEM), polyacrylate (ACM), fluorinated elastomers (FKM), nitrile rubber (NBR) and hydrogenated nitrile rubber (HNBR) are popular automotive industry elastomeric materials, especially for powertrain applications. New material technologies have been introduced to the automotive industry since the establishment of the first set of Standard Reference Elastomers (SRE) per SAE J2643 in 2004. Those advancements include low temperature flexible FKM materials, AEM and ACM cured with environmental friendly curative package - free of dio-tolylguanidine (DOTG), etc. Historically, automotive industries tend to use production rubber compounds molded by rubber part manufacturers for the development of engine oils or transmission fluids, if there is no Standard Reference Elastomer (SRE) available. The manufacturing process of molded slabs is usually not controlled and certified to a level required for standard reference. Large property variation of testing slabs is always a big concern during fluid development. An even worse situation is that a reference compound would be obsolete if the compound is out of production. There is a high demand from automotive fluid industries to develop new Standard Reference Elastomers (SREs) representing new material technologies that are commonly used in engine and transmissions. Those SREs shall be well controlled to avoid batch to batch variation, readily available with stabilized supplying source, and good traceability for slab quality monitoring.Copyright © 2011 SAE International doi: 10.4271/2011-01-00172011-01-0017 Published 04/12/2011 SAE Int. J. Mater. Manuf. | Volume 4 | Issue 1 40Downloaded from SAE International by Stony Brook Univ, Monday, August 13, 2018This study is aimed to developing additional SREs to SAE J2643 to enhance the portfolio on FKM, AEM and ACM to reflect advancements in elastomer technology, and make the elastomers set suitable for a variety of fluids. To achieve these goals, a team was formed involving experts industry wide. Participants include automobile original equipment manufacturers (OEMs), raw material manufacturers, a fluid additive company and a certified independent lab. A total of 14 compounds were defined by the team to cover elastomers used in automotive industries representing new technolog