| |
 |
Ruby Sapphire
For
this products we confirm RoHS-conformity
| Al203
|
| Hexagonale
rhomboedrique |
| Density
3,99 - 3,98 |
| Fusion
Temperature 2050°C |
| Thermal
expansion 5,4 x 10-6/°C face perp. axe C |
| 6,2
x 10-6/°C face paral. axe C |
| Hardness
Mohs 9 |
| Hardness
Knoop 1800 face perp. axe C |
| 2200
face paral. axe C |
| Refractive
index nd 1.760 face perp. axe C |
| 1,769
face paral. axe C |
| Dispersion
factor 0.011 |
| |
Quality
control
A.F.B.M.A.* GRADE TOLERANCES AND TERMINOLOGY.
GRADE TOLERANCE CHART |
 |
Basic
diameter: The size ordered which is the basis
to which the basic diameter tolerances apply. The basic
diameter is specified by a fraction plus a decimal or
a decimal only to the sixth place. (example: 1/4'' + .0002''
or .2502'' - 15/64'' +
.0003'' or .234675'').
Basic diameter tolerance: The maximum
allowable deviation of any ball diameter from the basic
diameter, in any shipments to fill orders for that basic
diameter.
Diameter tolerance per ball: The permissible
difference between the largest diameter and the smallest
diameter measurable on one ball.
Diameter tolerance per unit container:
The permissible range of the average diameters of the
individuals balls within any one unit container.
Grade: The numerical value of the diameter
tolerance per ball expressed in a millionth of an inch.
Marking Increments: The standard unit
steps in a millionth of an inch used to express the specific
diameter.
Some materials prevent us from obtaining a better result
of tolerance than those obtained at level 10. On the other
hand, some materials, mainly ceramics, make it possible
to obtain dimensions with a level 4 or 5 , RA is then
higher than in the above table. |
|
|
