The furnace industry has seen a remarkable growth in the production of custom-made, high temperature vacuum or argon atmosphere furnaces for growing sapphire crystals used in manufacturing of LEDs. These furnaces have unique and demanding hot zone designs for melting alumina in crucibles for precise, highly controlled crystal growth.
Tremor Alloys is fully aware of the various sapphire crystal growing methods and supplies components to the customers accordingly.
The hot zones in sapphire growing furnaces use Tremor Alloys’s molybdenum and tungsten products for furnace components and fixtures. These high temperature materials are characterized by their high thermal and electrical conductivity, low coefficient of thermal expansion, and excellent strength and stability at temperatures above 2,000°C.
Customer specific furnace components and fixtures for high temperature furnaces are uniquely designed and are supplied by Tremor Alloys.
Tungsten Crucibles – Powder Metallurgy
• Pure Tungsten (99.95% minimum)
• MoW Blend (percentages vary depending on customer requirements)
Tungsten Plate, Sheet, and Foil are used for:
• Seed Holders
• Heat Shields
• Heating Element Materials
• Other Support Components
TUNGSTEN PLATE, SHEET, AND FOIL
Tungsten mill products available from Tremor Alloys include plate, sheet, and foil with many options on width, length and thickness. Pure Tungsten flat rolled products are fabricated from pressed and sintered powder metallurgy ingot and are rolled to a wide range of plate, sheet, and foil thicknesses.
Flat rolled products
Pure Tungsten flat rolled products are fabricated from pressed and sintered powder metallurgy ingot and are rolled to a wide range of plate, sheet, and foil thicknesses.
The material is 99.95% pure Tungsten sheet and is normally supplied as-rolled in thicknesses below 0.030", and stress relieved at that thickness and above.
Thickness Tolerance |
||||
Thickness Tolerance |
Width Tolerance |
Length Tolerance |
Flatness Tolerance |
|
Thickness (Inches) |
(% of Thickness) |
(Inches) |
(Inches) |
(% Maximum) |
.1875 to .625 |
± 4 |
+.125 -0 |
+.125 -0 |
5 |
Over .500 to 1.125 |
± 5 |
+.125 -0 |
+.125 -0 |
5 |
Plate camber (edge straightness) = Maximum .0625 inch per foot of length.
Plate will be sheared, abrasive cut, band saw cut, or water jet cut to the tolerances shown.
Surface Condition
Tungsten plate is normally supplied with a uniform matte finish, clean and free from foreign matter. Major surface defects will be removed by grinding provided that such conditioning does not reduce dimensions below specified limits.
PURE TUNGSTEN SHEET 4202
Physical Characteristics:
Thickness Tolerance |
||
Thickness (Inches) |
Up to 12 Inches wide (Inches) |
Over 12 thru 24 Inches wide (Inches) |
0.005 to 0.008 |
± 0.0007 |
|
Over 0.008 to 0.011 |
± 0.001 |
|
Over 0.011 to 0.015 |
± 0.0012 |
|
Over 0.015 to 0.020 |
± 0.0015 |
|
Over 0.020 to 0.040 |
± 0.002 |
|
Over 0.040 to 0.187 |
± 5 % |
± 5 % |
*For thickness 0.040 to 0.187 inches; sheet will be sheared, abrasive cut, band saw cut, or water jet cut to the tolerances shown.
Bedsheet is sold as a useable width, therefore any cracks or delaminations on the edges are acceptable as long as a 6, 12 or 24 inch minimum width can be yielded from the material.
Length Tolerance
For specified lengths, the tolerance for all sizes is + .0625 - 0 inch per foot of length. Edge Straightness-Maximum camber is .0625 inch per foot of length.
Flatness Tolerance
The total deviation from flatness will not exceed 4 % maximum.
PURE TUNGSTEN FOIL 4201
Physical Characteristics
Thickness Tolerance |
||
Thickness Available |
Width (Inches) |
Tolerance (Inches) |
0.002 |
± 0.0003 |
250 to 6 |
0.003 |
± 0.0004 |
250 to 12 |
0.004 |
± 0.0005 |
250 to 12 |
0.0049 |
± 0.0007 |
250 to 12 |
Tolerance for intermediate thickness will correspond to next heavier thickness shown.
Width Tolerance |
|||
SLIT WIDTH |
SHEARED WIDTH |
(INCHES) |
(INCHES) |
Thickness (Inches) |
over .500 thru 6 wide Inches |
over 6 thru 12 wide Inches |
over .500 thru 12 wide Inches |
0.002 to 0.049 |
± .010 |
± .015 |
± .031 |
Tungsten discs, washers and squares for power semiconductors
Tungsten is widely used as contact materials in silicon controlled rectifiers diodes, transistors and thyristors (GTO’S). Other than in specialist applications, molybdenum is now accepted as the first choice mounting material for power semiconductor devices due to its significantly lower cost and weight.
The fact that both materials have a similar coefficient of expansion to silicon combined with high thermal conductivity makes them an ideal choice, especially in large area power devices where considerable heat is generated. Further applications include the use of molybdenum and tungsten as heat sink bases in IC’S, LSI’S and hybrid circuits.
TUNGSTEN DISCS |
||||
PRODUCTION METHOD |
THICKNESS |
DIAMETER |
||
mm |
inch |
mm |
inch |
|
PUNCH |
0.1 - 0.3 |
0.004 - 0.012 |
5.0 - 30.0 |
0.200 - 1.20 |
0.31 - 0.5 |
0.012 - 0.020 |
10.0 - 40.0 |
0.400 - 1.60 |
|
0.51 - 1.0 |
0.020 - 0.040 |
10.0 - 50.0 |
0.400 - 2.00 |
|
1.1 - 2.0 |
0.040 - 0.080 |
20.0 - 50.0 |
0.800 - 2.00 |
|
2.1 - 3.0 |
0.080 - 0.160 |
20.0 - 60.0 |
0.800 - 2.50 |
|
TUNGSTEN SQUARES |
||||
PRODUCTION METHOD |
THICKNESS |
DIAMETER |
||
mm |
inch |
mm |
inch |
|
SAW |
0.010 - 0.50 |
0.004 - 0.020 |
0.50 - 10.0 |
0.020 - 0.40 |
0.51 - 1.00 |
0.020 - 0.040 |
1.00 - 70.0 |
0.040 - 2.80 |
|
1.10 - 2.00 |
0.040 - 0.080 |
5.00 - 75.0 |
0.200 - 3.00 |
|
PUNCH |
0.20 - 0.50 |
0.008 - 0.020 |
5.00 - 25.0 |
0.200 - 1.00 |
0.51 - 1.00 |
0.020 - 0.040 |
15.0 - 55.0 |
0.600 - 2.00 |
|
1.10 - 2.00 |
0.040 - 0.080 |
10.0 - 75.0 |
0.400 - 3.00 |
|
EDM |
0.50 - 1.00 |
0.020 - 0.040 |
10.0 - 100.0 |
0.400 - 4.00 |
1.10 - 2.00 |
0.040 - 0.080 |
10.0 - 200.0 |
0.400 - 0.80 |
|
2.10 - 6.00 |
0.080 - 0.240 |
20.0 - 200.0 |
0.800 - 8.00 |
|
Length Tolerance
For specific lengths, tolerance is + .0625 - 0 inch per foot of length. Tungsten foil is supplied in a coil having a minimum internal diameter of 3 inches, with a minimum coil length of 10 feet.
Surface Condition
Foil will have a bright finish and will be essentially free of surface defects or edge delaminations as determined by visual examination. Special mirror finish material is available upon request.
TUNGSTEN-COPPER COMPOSITES
Tungsten-copper is a composite material that maintains the excellent performance of tungsten and copper, such as low heat resistance, excellent thermal and electrical conductivity. It can easily be machined into the required shape and finish. By using a tungsten skeleton and infiltrating it with copper, near-net-shape and relatively large pieces with different ratios of tungsten and copper can be produced.
There are two standard ratios available in the W-Cu
composite line: