Explanation of ASTM D2000 specifications
ASTM D2000 is a published specification that provides buyers and suppliers with a standard way of describing elastomeric materials through a composite identification number.
The ASTM D2000 designation includes the important elements of the corresponding elastomer. These elements are:
- standards
- year of last revision
- units
- Quality
- type and class
- hardness (durometer)
- tensile strenght
- Information for the additional requirements
For an explanation of the ASTM D2000 specifications see the example below:
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17
standards
The underlying norm. For rubber products, this is ASTM D2000.
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17
year of last revision
A two-digit number that indicates the year the standard was last revised. In this example 03.
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17
units
The units of measurement used for reporting test results. This is either M for metric units or a space if imperial units were used. In this example M.
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17
Quality
The grade of elastomer indicates the level of test requirements that exist for that elastomer. 1 is basic requirements only, 2-9 are additional testing requirements. In this example 2.
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17
type and class
ASTM D2000 classifies elastomeric materials based on their temperature resistance. The following requirements must be met after 70 hours, 100DC heat aging at different temperatures depending on the type.
Change in tensile strength: ±30%
Change in elongation: Max. -50%
Change in hardness: ±15 points
The class is used to distinguish materials based on their resistance to IRM 903 oil when immersed for a period of 70 hours.
The table below gives the letter designations for the type and class:
The table below indicates the most commonly used polymers of a particular type/class:
|
ASTM D2000 SAE J200 |
Type of the most commonly used polymer |
|
aa |
Natural rubber, recycled rubber, SBR, butyl, EP polybutadiene, polyisoprene |
|
B.A |
High temperature SBR and butyl blends |
|
B.C |
Chloroprene polymers (neoprene) |
|
BE |
Chloroprene polymers (neoprene) |
|
bf |
NBR polymers |
|
bg |
NBR polymers |
|
BK |
Organic dihalide polymers (Thickol), NBR |
|
APPROX |
ethylene propylene |
|
CE |
Chlorosulfonated Polyethylene (Hypalon) |
|
CH |
NBR polymers |
|
DF |
Polyacrylic (butyl acrylate type) |
|
IE |
Polyacrylic polymers, HNBR |
|
EE |
AEM, (Vamac) |
|
FC |
silicones (high resistance) |
|
FE |
silicones |
|
FK |
fluorosilicones |
|
GE |
silicones |
|
HK |
Fluoroelastomers (Viton™) |
|
KK |
perfluoroelastomers |
In this example, it is type B and class G.
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17
hardness (durometer)
The hardness of the material is given as a hardness range (durometer) in Shore A, ± 5 durometer. The value given is multiplied by 10 to determine the actual value of the elastomer. In this example, the hardness is 70 ± 5 durometer.
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17
tensile strenght
The next two digits increase the minimum tensile strength of the elastomer. This is given in MPa for metric units and in psi for imperial units. In this example, the minimum tensile strength is 17 MPa.
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17
Information for the additional requirements
The rest of the ASTM D2000 specification are suffixes used when the basic requirements for a particular type or class of elastomeric material are not sufficient to provide the desired properties in the end product.
The first letter of the suffix indicates the required test, as indicated in the table below:
|
suffix |
Required exam |
|
A |
heat resistance |
|
B |
compression set |
|
C |
Ozone or weather resistance |
|
D |
compression set resistance |
|
EA |
water resistance |
|
EF |
Fuel consistency |
|
EO |
Oil and lubricant resistance |
|
f |
Resistance to low temperatures |
|
G |
tear strength |
|
H |
flex crack resistance |
|
J |
abrasion resistance |
|
K |
Liability |
|
M |
fire resistance |
|
N |
shock resistance |
|
P |
discoloration resistance |
|
R |
resilience |
Each suffix is followed by digits after the first letter(s). The first digit stands for the test procedure to be used and the duration of the test procedure. The second digit indicates the test temperature.
Depending on the application, more than one specification in the suffix may be required to denote the desired mixture.
In the present example, the first letter “B” of the first suffix represents a compression set and “14” indicates test method D 395, Method B, max %, 22 hours at 100°C
ASTM D2000 03 M2 BG 717 B14 EO14 EO34 F17