SRMs 656, 676, 674b, 1878a and
1879a consist of high phase purity materials for use in the quantitative analysis of
samples by the internal standard method. SRM 656 consists of 2 silicon nitride
powders, one high in a, the other high in b. SRMs 640d, 660a, 675, and 1976 consist of materials with select crystallographic and microstructure properties
used in the evaluation of diffraction equipment for the following variables; 1)
d-spacing or line position, 2) line or instrument intensity, and 3) instrumental
or sample contributions to the shape of reflection profiles. SRM 1976, a sintered alumina plate, is also certified with respect to lattice parameters as
well as 12 relative intensity values from 25° to 145° 2q (Cu Ka). SRM 1990 is
certified for lattice parameter. SRM 1994 is certified for angular deviation of
the crystal axis relative to the surface normal.
|
REFERENCE |
DESCRIPTION |
XRD APPLICATION |
LATICE PARAMETERS (IN NM) |
UNIT SIZE (in g) |
SRM 640 D |
Silicon Powder |
Line Position Line Shape |
( 0,543159
± 0,000020) |
7,5 |
SRM 656 |
Silicon Nitride |
Quantitative Analysis |
a - (0,7752630 / 0,5619372) |
10 |
b - (0,7602293 / 0,2906827) |
10 |
SRM 660 A |
Lanthanum Hexaboride Powder |
Line Position Line Shape |
( 0,41569162
± 0,00000097) |
6 |
SRM 674 B |
X-RAY powder Diffraction Intensity
Set |
Quantitative Analysis |
( 0,5411651 )
|
10
|
CeO2 (fluorite structure) |
Cr2O3 (corundum strucuture) |
( 0,4958979 / 1,359592 ) |
10 |
TiO2 (rutile) |
(0,4593927 / 0,2958875 ) |
10 |
ZnO (wurtzite structure) |
( 0,3249897 / 0,520653 ) |
10 |
SRM 675 |
Mica |
Line Position - Low 2q |
0,998104 |
7,5 |
SRM 676 A |
Alumina Powder for Quantitative
Analysis by X-ray Diffraction |
Quantitative Analysis |
0,47590914 / 1,2991779 |
20 |
SRM 1878 A |
Respirable Alpha Quartz |
Quantitative Analysis |
|
5 |
SRM 1879 A |
Respirable Cristobalite |
Quantitative Analysis |
|
5 |
SRM 1976 A |
Instrument Response Standard for
X-ray Diffraction |
|
0,4758877
± 1,2992877 |
25,6 mm x 2,2 mm |
SRM 1990 |
Single Crystal Diffractometer
Alignment Standard |
Quantitative Analysis |
|
3 Spheres |
SRM 1994 |
Standard Silicon Single Crystal Wafer
for Crystalline orientation |
Crystalline Orientation |
|
100 mm wafer |
SRM 1995 |
Standard Sapphire Single Crystal
Wafer for Crystalline Orientation |
Crystalline Orientation |
|
50 mm wafer |
SRM 2000 |
Calibration Standard for High-Resolution
X-Ray Diffraction |
Line Position |
|
( 25 x 25 x 0,725 ) mm |
|
Values in parentheses are not certified but are provided as
reference values or are given for information only. |
SECONDARY FERRITE STANDARD
|
Secondary Ferrite Standards, RM8480 and RM8481, are designed for use in welding
construction
and repair operations where the ferrite content of corrosive-resistant
austentitic stainless steel
welds must be controlled within tight ranges. RM8480 covers the low range
(ferrite numbers 0 to
30) and RM8481 covers the high range (ferrite numbers 30 to 120).
These standard required the development of an advanced calibration procedure.
The process
included over 25 000 individual measurements.
|
REFERENCE
|
DESCRIPTION
|
UNIT SIZE
|
RM 8480 |
Eight individually measured specimens |
10 mm x 12 mm x 20 mm |
RM 8481 |
Eight individually measured specimens |
10 mm x 12 mm x 20 mm |
|
QUARTZ CONTENT IN SILICA MATRIX FOR POWDER X-RAY DIFFRACTION
|
The set is designed for the calibration in quantitative analyses by the X-ray
diffraction and other
structure (sensitive analytical techniques).
The issue materials are dinas as matrix and the natural crystalline alpha quartz
from Brazil as certified constituent. |
PROCEDURE OF PREPARATION : |
Both basic components
were first ground separately by the continuous vibration cup mill. Reground
materials we’re carefully mixed to achieve the content of 5, 10, 20 and 40 wt %
of alpha quartz in the consecutive samples.
The homogeneity tests we’re performed by measuring the intensity of the main
diffraction line of alpha quartz (hhl=101) using 21 random selected packings (bottles)
from each RM of the set.
The certified values are based on the procedure of preparation (according to the
ISO Remco Guide 35 – 1985 (E)) i.e. the mass portions of both constituents and
are verified by the complementary XRD measurements. The correction for the
amorphous phase decrease, which was determined by wel way (powder diffraction,
vol.4, March 1989, page 9-13) and represent decrease by 5.1 wt %.
The certified values after correction on the amorphous phase are as follows:
|
REFERENCE
|
CONC. (wt %) OF QUARTZ
|
UNIT SIZE
|
Q1 |
4 |
50 g each in bottle |
Q2 |
9 |
Q3 |
19 |
Q4 |
38 |
|
|