Buy ASTM D TEST METHODS FOR CARBON BLACK – DISPERSION IN RUBBER from SAI Global. However, unvulcanized compounds should be compressed in a mold for 5 minutes at °C to remove the air holes before testing. ASTM D , Method B , is a. ASTM D Standard Test Methods for Carbon Black-Dispersion in Rubber.
|Published (Last):||4 January 2016|
|PDF File Size:||20.90 Mb|
|ePub File Size:||19.26 Mb|
|Price:||Free* [*Free Regsitration Required]|
Taking into account microscope tube corrections, objectives should be selected so that magni? Continue brushing gently to remove all wrinkles. For each letter rating the amount of undispersed black is the same throughout the six agglomerate size categories.
NOTE 2—Most agglomerates are not composed entirely of carbon black. In cases of dissimilarity in the size and frequency of the agglomerates in the specimen and those of the standards, the operator shall assign the rating that in his judgment is most applicable.
The percent dispersion values obtained by Test Method B are used to establish the dispersion index scale for different rubber formulations.
ASTM D – 14 Standard Test Methods for Carbon Black—Dispersion in Rubber
Then proceed as in 7. This will encompass all agglomerates down to about 5?
Because it can be observed side by side with unknown samples under identical conditions, a control compound is more accurate than the photographic aztm in discerning small deviations from what is considered the norm for a speci? ASTM D e1. The chart is graduated from A to H in the direction of atsm percent dispersion and from 1 to 6 in the direction of increasing agglomerate size.
A large sheet of glass should? Rubbers that contain relatively high amounts of inorganic pigments are particularly prone to cause knife chipping and may require a fresh knife for each different specimen.
Mill and cure in accordance with Practice D Test Method A—Visual Inspection. E2663 standards give the following percent dispersion ratings by the Agglomerate Count Method: Visual Dispersion Rating 4 3 2 1 to to to to 5 4 3 2 Classi?
The tear may be initiated by a small cut. In instances of high agglomerate frequency, the aastm of stocks of this type may show a general roughness or? For specimens that are too soft to be microtomed at liquid CO2 temperatures, pour a little liquid nitrogen onto the specimen block while it is in position on the freezing stage.
The section will be curled up in a small tight roll.
Standard – Standard Test Methods for Carbon Black-Dispersion in Rubber ASTM D –
Count all squares that are at least half covered by an agglomerate of carbon black. Certain compounds for example, NR and IR are particularly prone to very small black agglomerations which are difficult to resolve by the Visual Inspection Method.
Fracture with the glass pliers as before. Take care that the score mark does not actually extend all the way to the side faces or chipping may result. This test method cannot be used for compounds that contain? The values in parentheses are for information only. OE-SBR rubbers require about 30 to min cure. For photomicrographs a 43 plane objective and a periplanatic eyepiece are recommended. A sheet of plate glass on the surface of the vibration isolator is suitable for this purpose.
Summary of Test Method NOTE 1—Glass knives should be stored in a desiccator of absolute ethyl alcohol chemically pure to conserve the life of the knive edges.
The precison parameters should not be used for acceptance or rejection testing of any group of materials without documentation that they are applicable to those materials and the speci? In the cutting position d2663 clamp handle should be facing upright.
Standard Test Methods for Carbon Black—Dispersion in Rubber
A number in parentheses indicates the year of last reapproval. The head of the brass screw shall be 18 mm in diameter and shall extend 3 mm above the TFE-? IIR vulcanizates containing 50 phr of N carbon black or oil extended SBR stocks with 50 phr asttm a N black require about a 1-min freeze.
In borderline cases, use fractional ratings, for example, 31?
Standard Test Methods for Carbon Black-Dispersion in Rubber
Repeat the leveling operation and complementing height correction until the indicator bar remains close to the center point between HIGH and LOW across the entire cm trace. Four test methods are described as follows:.
If pieces other than 2-mm sheets are used, they should? After cure, scrape off the excess peroxide from the sample surface and proceed with sectioning in the standard manner, taking care not to pare down below the cured surface layer.
Avoid excessive time lapses between succeeding cuts, as this will lead to thickening due to thermal expansion. Prior to fracture, it is also important that the glass be free of dirt.