Understanding Conductive Layer Deposits: Test Method Development for
                    Lubricant Performance Testing for Hybrid and Electric Vehicle
                    Applications

Hunt, Gregory J.; Javaid, Rahmeen; Simon, James E.; Peplow, Mitchell; Prengaman, Christopher

doi:10.4271/14-12-02-0014

Cited by 3 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This has prompted the industry to develop two new corrosion tests; a wire corrosion test (WCT) developed at the Lubrizol Corporation and introduced in 2016 (Gahagan & Hunt, 2016), and a conductive deposit test (CDT) developed at IFAS (Institute for Fluid Power Drives and Systems) at RWTH Aachen University. Both test methods have gained broad acceptance among groups developing future EDU lubricants (Canter, 2022;Hunt et al, 2023). In particular, much has been published on the WCT (Hunt, 2017;Hunt et al, 2017;Hunt, 2018), including its application to other metals (Bares et al, 2020).…”

Section: Corrosion Characteristicsmentioning

confidence: 99%

A brief review of the rapid transformation of driveline lubricants for hybrid electric and electric vehicles

Newcomb

2023

Front. Mech. Eng.

View full text Add to dashboard Cite

Hybrid electric and electric vehicles have represented a small portion of the automotive market for many years and mainly use current lubricants, typically automatic transmission fluids (ATFs). However, regulatory compliance to limit greenhouse gases and increased consumer demand have resulted in a rapid global transition to electrified vehicles. This has prompted the need for new advances in vehicle technology to improve efficiency and thereby increase range. Enabling and optimizing such advances requires a new generation of driveline lubricants. Incorporating an electric motor in a transmission or axle, where the motor is exposed to the gear box lubricant, creates new challenges that focus attention on lubricant characteristics that were previously not differentiating features, for example, electrical and thermal properties. Additionally, lubricants must now also be compatible with the constituents used in electric motors which include new polymeric materials and, in some cases, exposed copper. Compatibility tests of these polymers vary within the industry and the risk of copper corrosion in these applications is not always properly assessed by current specification tests. In this paper we will begin with a brief history of electric vehicles, highlight how driveline lubricants, specifically ATFs, have evolved over the years to meet new hardware requirements and then describe the performance requirements expected of lubricants specifically designed for vehicles with electric drive units (EDUs). Our primary goal, however, is to summarize the recent literature that illustrates the changing importance of various lubricant performance properties, new proposed test methods and offer some insight into future e-lubricant evolution.

show abstract

Section: Corrosion Characteristicsmentioning

confidence: 99%

A brief review of the rapid transformation of driveline lubricants for hybrid electric and electric vehicles

Newcomb

2023

Front. Mech. Eng.

View full text Add to dashboard Cite

show abstract

100 Years of Corrosion Testing—Is It Time to Move beyond the ASTM D130? The Wire Corrosion and Conductive Deposit Tests

Hunt,

Choo,

Newcomb

2023

SAE Int. J. Fuels Lubr.

View full text Add to dashboard Cite

<div>The ASTM D130 was first issued in 1922 as a tentative standard for the detection of corrosive sulfur in gasoline. A clean copper strip was immersed in a sample of gasoline for three hours at 50°C with any corrosion or discoloration taken to indicate the presence of corrosive sulfur. Since that time, the method has undergone many revisions and has been applied to many petroleum products. Today, the ASTM D130 standard is the leading method used to determine the corrosiveness of various fuels, lubricants, and other hydrocarbon-based solutions to copper. The end-of-test strips are ranked using the ASTM Copper Strip Corrosion Standard Adjunct, a colored reproduction of copper strips characteristic of various degrees of sulfur-induced tarnish and corrosion, first introduced in 1954. This pragmatic approach to assessing potential corrosion concerns with copper hardware has served various industries well for a century.</div> <div>Driveline lubricants have always been required to protect hardware, and transmission fluid specifications have always included a version of the copper corrosion strip test to assure this. In conventional transmissions, copper and its alloys are present in the form of mechanical parts such as bushings, bearings, and washers. Corrosion of these parts, while detrimental, does not typically result in immediate failure. However, the incorporation of electronics and electric motors has resulted in new failure modes which can have immediate and devastating consequences. Designing a lubricant to protect new electrified hardware requires an understanding of corrosion that occurs under actual operating temperatures, as well as potential damage from corrosion products. While the ASTM D130 provides general insight regarding the susceptibility of the hardware to corrode, the information is typically gleaned at elevated temperatures, and no information is gathered about the impact of corrosion products. The ASTM D130 is simply not sufficiently specific to adequately assess the risk of these new failure modes that may occur within electric drive units (EDUs). Newer methods, in particular, the wire corrosion test (WCT) and conductive deposit test (CDT), have been created to fill these gaps.</div> <div>In this article, we provide the history of the creation and evolution of the ASTM D130 standard, which is important in understanding both its significance and limitations. We then assess the corrosion characteristics of five lubricants using both the ASTM D130 strip method and the WCT method. We contrast these results, which demonstrate the greater understanding gleaned from the WCT. We then assess the five lubricants with the CDT, which provides insight into whether the corrosion products might endanger the system. We conclude that both the WCT and CDT are needed to provide a holistic understanding of corrosion in electrified hardware necessary to minimize the risk of corrosion-related failure modes. We anticipate that the WCT and CDT will establish themselves in original equipment manufacturer (OEM) specifications over the next decade and will provide a useful assurance of lubricant performance in corrosion, especially for hybrid (HEVs) and electric vehicles (EVs).</div>

show abstract

Characterization of E-Fluids from Laboratory Analysis to Test Bench and Test Stands

Gurski,

Pelz,

Schäfer

et al. 2023

SAE Technical Paper Series

View full text Add to dashboard Cite

<div class="section abstract"><div class="htmlview paragraph">The trend in the automotive industry towards e-drive results in new challenges for the lubricants and fluids used. Due to the limited amount of industry standards, many characterization methods and processes for e- fluids have been developed by OEMs, the oil and additive industry and independent laboratories during the last years. In addition, national and international committees start to implement new test standards with defined precisions for this rapidly changing application. A combination of different laboratory tests to screen a fluid regarding specific attributes can be conducted. This can reduce the number of testing candidates significantly, before committing to more expensive and time-consuming engine or field trial tests. This paper gives a brief overview over the most used tests in the industry for these purposes.</div></div>

show abstract

Understanding Conductive Layer Deposits: Test Method Development for Lubricant Performance Testing for Hybrid and Electric Vehicle Applications

Cited by 3 publications

References 0 publications

A brief review of the rapid transformation of driveline lubricants for hybrid electric and electric vehicles

A brief review of the rapid transformation of driveline lubricants for hybrid electric and electric vehicles

100 Years of Corrosion Testing—Is It Time to Move beyond the ASTM D130? The Wire Corrosion and Conductive Deposit Tests

Characterization of E-Fluids from Laboratory Analysis to Test Bench and Test Stands

Contact Info

Product

Resources

About