ASTM D8544-24

Standard Test Method for Determination of Conductive Deposits of Electrical and Mechanical Components from Fluids in Liquid and Vapor States within an Electrically Charged System

SIGNIFICANCE AND USE
5.1 This method may be utilized to assess the suitability of a fluid for use in electric vehicle drivelines and other powered or corrosive applications to form conductive deposits and corrosion tendencies with copper or other materials. Fluids known to perform poorly in the field have been shown to fail this test and fluids known to perform well in the field have been shown to pass this test. Comparison of fluids using this test is likely to be an indicator of which fluids may have better field performance. This test is recommended in the SAE J3200, Surface Vehicle Information Report Fluid for Automotive Electrified Drivetrains.
SCOPE
1.1 This test method covers the basic operation of the conductive deposit test. The apparatus is utilized to monitor the formation of dendrites and deposits that are conductive and may form under oxidation conditions of fluids used in electric vehicles and other industries where electronics are involved. The oxidation conditions can vary from 80 °C to 180 °C with very specific circuit boards, under power, and monitoring changes in conductance over time. Both the liquid and vapor areas are monitored for this condition over time. Variables in temperature, voltage, and time can be altered according to the industry need. A reported index based on the rate of deposit formation may be implemented. The typical testing is performed at 150 °C over a period of up to 500 h with a monitored voltage applied.  
Note 1: Testing up to 1000 h has some historical significance and is an option but not covered in this test method.  
1.2 This test method has an interim precision. An interlaboratory study of this test method is being conducted and a complete precision statement is expected to be available on or before December 2024.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 29-Feb-2024
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.09.0G - Oxidation Testing of Engine Oils

Relations

• Refers: ASTM E986-04(2024) - Standard Practice for Scanning Electron Microscope Beam Size Characterization
• Effective Date: 01-Apr-2024
• Refers: ASTM E986-04(2017) - Standard Practice for Scanning Electron Microscope Beam Size Characterization
• Effective Date: 01-Jun-2017

Overview

ASTM D8544-24 is the Standard Test Method for Determination of Conductive Deposits of Electrical and Mechanical Components from Fluids in Liquid and Vapor States within an Electrically Charged System. Developed by ASTM International, this method provides a systematic approach to evaluate the tendency of fluids, particularly lubricants and coolants used in electric vehicle (EV) drivelines and other electronics-intensive or corrosive environments, to form conductive deposits. These deposits can impact the performance and lifetime of electrical components, particularly those containing copper or similar materials. The test simulates actual operating conditions, leveraging controlled temperature and voltage to monitor the formation of deposits over time, making it an essential tool in assessing fluid suitability for advanced applications.

Key Topics

• Purpose
  The main purpose of ASTM D8544-24 is to assess the suitability of fluids for use in systems where the formation of conductive deposits could affect electrical or mechanical performance, such as EV drivelines and electronic assemblies.

• Test Scope

  • Covers the operation of a conductive deposit test using a standardized apparatus.
  • Simulates oxidation conditions typically between 80 °C to 180 °C, with common testing at 150 °C for up to 500 hours.
  • Monitors both liquid and vapor phases for deposit formation by tracking the electrical conductance changes between traces on a powered circuit board.

• Test Indicators

  • Formation of conductive dendrites and deposits that reduce resistance between non-contacting traces.
  • Calculation of a Conductive Deposit Factor (CDF) to quantify deposit formation rate.
  • Test considered “pass” if no failures (shorting or corrosion) occur within the test duration.

• Relevance to Industry Standards

  • Referenced in SAE J3200 for automotive electrified drivetrain fluids.
  • Aligns with internationally recognized standardization principles.

Applications

ASTM D8544-24 is valuable in several key fields:

• Electric and Hybrid Vehicle Drivelines
  Helps laboratory and industry professionals compare and qualify fluids designed for use in high-voltage environments, ensuring longer component life and reduced risk of electrical failure.

• Industrial Electronics Cooling and Lubrication
  Used by manufacturers of lubricants and dielectric fluids to validate their products for compatibility with sensitive electronics and copper-containing systems.

• Corrosive and Powered Environments
  Useful for any system where electrical and mechanical component integrity relies on minimal formation of conductive or corrosive deposits - including robotics, renewable energy installations, transformers, and more.

• Lubricant Formulation and Quality Control
  Enables R&D teams to test new formulations or batches against a known benchmark, supporting continuous quality improvements and regulatory compliance.

• Post-Test Analysis
  After testing, further analyses (such as inductively coupled plasma, visual, or SEM analysis) can help investigate deposit composition for root cause studies or research.

Related Standards

Organizations and laboratories applying ASTM D8544-24 should also be aware of the following standards for a comprehensive assessment of fluids and their corrosion behavior:

• ASTM D130
  Standard Test Method for Corrosiveness to Copper from Petroleum Products by Copper Strip Test

• ASTM D4057
  Practice for Manual Sampling of Petroleum and Petroleum Products

• ASTM D4175
  Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants

• ASTM D5185
  Test Method for Multielement Determination of Used and Unused Lubricating Oils and Base Oils by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES)

• ASTM E986
  Practice for Scanning Electron Microscope Beam Size Characterization

• SAE J3200
  Surface Vehicle Information Report: Fluid for Automotive Electrified Drivetrains

Practical Value

By implementing ASTM D8544-24, industries can:

• Reduce risk of unexpected failures in electrical systems due to fluid-induced conductive deposits.
• Select, benchmark, and qualify fluids tailored for high-performance, electronics-driven environments.
• Ensure compliance with modern automotive and industrial electronics reliability requirements.
• Provide confidence in product quality during both development and production phases.

Regularly applying ASTM D8544-24 as part of a robust fluid qualification and monitoring program supports the maintenance of system integrity, reduces warranty claims, and enhances end-user satisfaction in electrical and electronic systems.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D8544 − 24
Standard Test Method for
Determination of Conductive Deposits of Electrical and
Mechanical Components from Fluids in Liquid and Vapor
States within an Electrically Charged System
This standard is issued under the fixed designation D8544; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
1.1 This test method covers the basic operation of the
conductive deposit test. The apparatus is utilized to monitor the
2. Referenced Documents
formation of dendrites and deposits that are conductive and
2.1 ASTM Standards:
may form under oxidation conditions of fluids used in electric
vehicles and other industries where electronics are involved. D130 Test Method for Corrosiveness to Copper from Petro-
leum Products by Copper Strip Test
The oxidation conditions can vary from 80 °C to 180 °C with
D4057 Practice for Manual Sampling of Petroleum and
very specific circuit boards, under power, and monitoring
Petroleum Products
changes in conductance over time. Both the liquid and vapor
D4175 Terminology Relating to Petroleum Products, Liquid
areas are monitored for this condition over time. Variables in
Fuels, and Lubricants
temperature, voltage, and time can be altered according to the
D5185 Test Method for Multielement Determination of
industry need. A reported index based on the rate of deposit
Used and Unused Lubricating Oils and Base Oils by
formation may be implemented. The typical testing is per-
Inductively Coupled Plasma Atomic Emission Spectrom-
formed at 150 °C over a period of up to 500 h with a monitored
etry (ICP-AES)
voltage applied.
E986 Practice for Scanning Electron Microscope Beam Size
NOTE 1—Testing up to 1000 h has some historical significance and is an
Characterization
option but not covered in this test method.
2.2 SAE Standard:
1.2 This test method has an interim precision. An interlabo-
SAE J3200 Fluid for Automotive Electrified Drivetrains
ratory study of this test method is being conducted and a
complete precision statement is expected to be available on or
3. Terminology
before December 2024.
3.1 Definitions:
1.3 The values stated in SI units are to be regarded as
3.1.1 For definitions of terms used in this test method, refer
standard. No other units of measurement are included in this
to Terminology D4175.
standard.
3.1.2 conductive deposits, n—in electric vehicle drivelines
1.4 This standard does not purport to address all of the
and other powered systems, material adhering to or collecting
safety concerns, if any, associated with its use. It is the
on electrical components that conduct electricity.
responsibility of the user of this standard to establish appro-
3.1.3 conductive deposit factor, n—a value that is used to
priate safety, health, and environmental practices and deter-
estimate the amount of conductive deposits being formed over
mine the applicability of regulatory limitations prior to use.
time and is calculated using a log summation of the area
1.5 This international standard was developed in accor-
between the beginning resistance baseline and the resistance
dance with internationally recognized principles on standard-
curve formed by the arcing conductive deposit events over
ization established in the Decision on Principles for the
time.
Development of International Standards, Guides and Recom-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
This test method is under the jurisdiction of ASTM Committee D02 on contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Standards volume information, refer to the standard’s Document Summary page on
Subcommittee D02.09.0G on Oxidation Testing of Engine Oils. the ASTM website.
Current edition approved March 1, 2024. Published March 2024. DOI: 10.1520/ Available from SAE International (SAE), 400 Commonwealth Dr., Warrendale,
D8544-24. PA 15096, http://www.sae.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D8544 − 24
3.1.3.1 Discussion—See Appendix X1 for more informa- performance. This test is recommended in the SAE J3200,
tion. Surface Vehicle Information Report Fluid for Automotive
Electrified Drivetrains.
3.1.4 continuity loop, n—on the circuit board there is a
circuit board trace made of conductive copper that outlines the
6. Apparatus
outside of the board in the liquid and vapor levels; this is
6.1 Conductive Deposit Test (CDT) Assembly, consisting of
monitored during the test for consistent continuity; should the
a blank board and a circuit board placed in the circuit board
copper become depleted at any time during the test, any data
holder so the measurement circuit faces the blank board with a
after the copper is depleted, where the circuit becomes open
tight gap around the measurement circuit. Additional metal
and non-conductive, the test from that point to the end of the
clips are used between the wicking holes to ensure correct gap
test becomes invalid.
spacing (see equipment manual for spacing details).
3.1.5 inductively-coupled plasma (ICP), n—a high tempera-
6.2 Circuit Board Holder , to hold the board stack, provide
ture discharge generated by flowing an ionizable gas through a
precise spacing between the boards, and position the boards in
magnetic field induced by a load coil that surrounds the tubes
the test fluid and the test cell.
carrying the gas.
4,5
6.3 Blank Board , made of FR4 material with the same
3.1.6 non-conductive deposits, n—in electric vehicle driv-
elines and other powered systems, material adhering to or dimensions as the circuit board.
4,5
collecting on electrical components that do not conduct elec-
6.4 Circuit Board , made of FR4 material with a circuit of
tricity.
bare copper for resistance in the liquid and vapor phases of the
3.1.7 scanning electron microscope (SEM), n—a type of specimen and continuity measurement on one side, and con-
electron microscope that produces images of a sample by
nections to the data acquisition unit (see equipment manual for
scanning the surface with a focused beam of electrons. circuit details and board dimensions).
4,5
6.5 Conductive Deposit Circuit Board Test Instrument ,
4. Summary of Test Method
consisting of a constant-temperature bath, data acquisition unit,
4.1 A powered circuit board with bare copper traces is
carousel (optional), test cell, and circuit board holder, provides
placed in a stack with a board with no traces to create tightly
the means of applying test conditions to the specimen, circuit
controlled gaps and inserted to a lubricant in a test cell and
board, and blank board, to determine the tendency of the test
heated to 150 °C. The test cell with the board assembly along
fluid to create conductive deposits on electrical components
with the fluid and vapor above the fluid are enclosed, but not
with exposed copper.
sealed, for a duration of up to 500 h. Other material,
6.6 Constant-temperature Bath, a liquid or dry bath capable
temperatures, timeframes, and power requirements may be
of controlling the bath medium to within 0.5 °C of the set point
utilized but were not studied in the precision determined. The
with a set point from 40 °C to 180 °C.
conductance between non-contacting traces is measured
6.7 Data Acquisition Unit , consisting of electrical circuitry
throughout the duration of the test in both the liquid and vapor
that delivers low power to each circuit, reads the resistance and
areas of the test cell. The overall rate of change indicates a
continuity measurements from each circuit, and reads the
shorting failure caused by the formation of conductive deposits
liquid and vapor temperature measurements of the bath.
between traces. Meanwhile the current, in a continuous con-
ductive loop on the circuit board, is monitored to ensure that
6.8 Syringe, 20 mL capacity, with 1 mL markings.
copper has not been corroded so far to create unintended gaps
6.9 Syringe, approximately 50 mL capacity, for use with the
in the traces that would hide shorting failures. Fluids not
liquid bath only, capable of transferring silicone oil, for
creating shorting failures or unintended gaps in the traces for
adjusting the level of the heating medium in the liquid bath
the full duration of the test are considered to have good
once it has reached temperature.
performance. Post analysis, such as elemental analysis by ICP,
SEM, visual ratings, or other practices may be conducted on 6.10 Test Cell , made of stainless steel with set internal
the fluid after test and compared to results from fresh fluid for dimensions (see equipment manual for dimensions) to hold the
additional information. test fluid and circuit board stack.
5. Significance and Use
The sole source of supply of the apparatus known to the committee at this time
5.1 This method may be utilized to assess the suitability of is Tannas Co., 4800 James Savage Rd., Midland, MI 48640, www.tannasking.com.
If you are aware of alternative suppliers, please provide this information to ASTM
a fluid for use in electric vehicle drivelines and other powered
International Headquarters. Your comments will receive careful consideration at a
or corrosive applications to form conductive deposits and
meeting of the responsible technical committee, which you may attend.
corrosion tendencies with copper or other materials. Fluids
The Conductive Deposit Circuit Board Test Instrument, Circuit Board, and the
use of the Blank Board in this test are covered by a patent (pending). Interested
known to perform poorly in the field have been shown to fail
parties are invited to submit information regarding the identification of an
this test and fluids known to perform well in the field have been
alternative(s) to this patented item to the ASTM International Headquarters. Your
shown to pass this test. Comparison of fluids using this test is
comments will receive careful consideration at a meeting of the responsible
likely to be an indicator of which fluids may have better field technical committee, which you may attend.
D8544 − 24
7. Reagents and Materials 11.2 Test a sample of the CDT reference fluid (commer-
cially available) according to the schedule dictated by internal
7.1 Purity of Reagents—Reagent grade chemicals shall be
6 quality control procedures to verify that temperature control
used in all tests. Unless otherwise indicated, it is intended that
and data collection are functioning correctly.
all reagents conform to the specifications of the Committee on
Analytical Reagents of the American Chemical Society where
12. Procedure
such specification are available. Other grades may be used,
provided it is first ascertained that the reagent is of sufficiently
12.1 Set up the constant-temperature bath according to the
high purity to permit its use without lessening the accuracy of
manufacturer’s instructions.
the determination.
12.2 Ensure the test cells and circuit board holders are dry
7.2 Hydrocarbon Solvent, such as cyclohexane or other
and debris free utilizing dry air.
suitable solvent—Reagent grade. (W
...