13.10/2023
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11.07/2023
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Molybdenum sheets, plates
Molybdenum products:
powders, sheets, plates, discs, sputtering targets, electrodes, rods, crucibles, pans, boats, screens.
The following brands of sheets and plates are produced:
- sheets from Mo-PM brand alloy;
- high-precision molybdenum rolled products.
Application:
- radiators, screens, and boats for high-temperature ovens operating in a vacuum, in hydrogen, or in an inert-gas atmosphere at temperatures of up to 2100 оС, as well as screens and other components for apparatuses used to grow sapphire monocrystals;
- substrata in the form of discs for silicon powder rectifiers;
- sputtering targets and components of magnetrons and other electric tubes.
Chemical composition
Contemporary powder metallurgy methods ensure a high level of molybdenum purity in terms of metallic intersitial impurities (C, N, O, H), a microstructure necessary for application in the electronics industry and as heat-resistant constructional material in electronics and other devices that operate under extremely high temperatures.
The chemical composition of stock-produced sheets meets or exceeds the norms established for raw molybdenum powder.
Since 2002, the company has primarily used Mo powder 99,95 molybdenum powder to produce sheet products.
Guaranteed chemical composition of Mo powder 99,95 molybdenum powder.
Brand | Minimum Мо, %* | Chemical composition, ppm, maximum | ||||||||||||
Fe | Al | Ni | Si | Mg | Na | K | Ca | W | Mn | Zn | C | ∑Ме** | ||
Mo powder 99,95 | 99,95 | 100 | 30 | 50 | 50 | 20 | 30 | 80 | 40 | 130 | 10 | 5 | 40 | 500 |
*The weight percentage of Mo in Mo powder 99,95 is determined by subtracting from 100% the sum of all metallic admixtures tested for using mass spectrometry with an inductively coupled plasma ICP-MS.
The gas-forming admixtures C, O, N, H, S, F, Cl are not included in calculations of molybdenum percentage.
** ∑Ме – the sum of metallic admixtures
Dimensions, mechanical and structural characteristics, and surface quality
Mo-PM rolled products are made:
- with finishing by pressure shaping: hot-rolled (HR) with a thickness of 1-45 mm and cold-rolled (CR) with a thickness of 0.3 (0.2)-0.9 mm;
- based on the degree of rolling accuracy: products of normal and enhanced accuracy;
- based on materials used, hot-rolled sheets – annealed or without annealing with a surface cleansed of oxides, based on the client's order;
- in moderate dimensions with scissor-trimmed edges, or a plate with a mechanically milled or grinded surface with a thickness of more than 5 mm;
- with monitoring of the surface condition, mechanical properties and microstructure.
Dimensions and mechanical properties of Mo-PM brand sheets and plates
Thickness s, mm |
Variation s, mm |
Width, mm |
Length, mm |
σв, Н/ mm 2 (kgf/ mm 2 ), minimum |
δ, %, minimum |
0,2-0,4 | ± 0,05 (0,03) | 50-300 | 150-1000 | * | * |
0,5-0,7 | ± 0,05 | 50-500 | 150-1350 | * | * |
0,8-0,9 | ± 0,08 | 50-500 | 150-1350 | 690 (70) | 8 |
1,0 – 2,0 | +0,20 -0,15 | 50-600 | 150-1600 | 690(70) | 8 |
2,2 – 4,0 | +0,25-0,15 | 50-600 | 150-1250 | 690(70) | 10 |
4,5 – 6,0 | +0,30-0,20 | 50-600 | 150-1000 | 640 (65) | 8 |
6,5 – 10,0 | ± 0,40 | 100-600 | >150 | ** | ** |
10,5 -20,0 | ± 1,0 | 100-400 | >150 | ** | ** |
20,5 – 30,0 | ± 1,5 | 100-400 | >150 | ** | ** |
>30 до 45 | In accordance with plans agreed upon with the client |
Upon agreement with the client, sheets are delivered without determining their mechanical properties. In this case, the manufacturer guarantees mechanical properties in keeping with the standard.
* Sheets with a thickness of 0.7 and more are tangent bending-tested for parallelness with the following thicknesses in mm:
5 –for sheets with a thickness of > 0.2 to 0.5 mm;
8 –for sheets with a thickness of > 0.5 to 0.7 mm, inclusive.
** Mechanical properties of sheets (plates) with a thickness of more than 6 mm are determined at the client's request.
Norms are set based on agreement with the client.
Non-flatness:
- of sheets with a thickness of 1-3 mm does not exceed 2 mm per 100 mm of length;
- of sheets with a thickness of over 3 mm does not exceed 1 mm per 100 mm of length.
Surface condition:
rolled stock is delivered without cracks, slivers, backfins, rolled-in foreign particles, blemishes, or edge lamination.
Annealing to remove internal stress:
hot-rolled sheets are manufactured with annealing to remove internal stress, or without annealing (based on the client's order) with a surface cleansed of oxides.
Microstructure:
in sheets (with a thickness of 1-6 mm), a full recrystalliation structure, lamination and foreign particles, tested for using supersonic defectoscopy, are not allowed.
Samples of the microstructure and mechanical properties of a Mo-PM sheet, annealed to remove internal stress:
*Fig.1: A Mo-PM sheet with a thickness of 2 mm. Microstructure x100, transverse rolling.
*Fig.2: A Mo-PM sheet with a thickness of 5.4 mm. Microstructure x100, transverse rolling
Chemical composition.
High-quality raw materials – molybdenum powder with a purity of Mo 99.95-99.98% - are used to make the sintered semifinished products from which sheets are produced.
Chemical composition of Мo99.95-PM rolled stock
Мo99.95-PM |
Мо, %, minimum * |
Maximum admixtures, ppm | |||||||||
O | N | C | Fe | Al | Ni | Si | Mg | Ca | ΣМе** | ||
Guaranteed composition | 99,95 | 70 | 50 | 100 | 100 | 50 | 50 | 100 | 30 | 70 | 500 |
Typical values | >99,97 | 40-70 | 20-30 | 15-30 | 37-45 | <10 | <10 | <10 | <10 | <10 | < 300 |
* Content of the base metal, not including gas-forming elements.
** Σ Ме - total metallic admixtures.
PM – Powder Metallurgy
Dimensions, mechanical and structural properties, and surface quality
Mo99,95-PM rolled stock is produced:
- based on finishing by pressure treatment – hot-rolled and cold-rolled;
- based on the condition of the material – thermally treated, with annealment to remove internal stress, unless the client makes other requests;
- based on the client's request – with an untreated surface following rolling, or with a mechanically or chemically cleansed surface, or with a surface treated mechanically with milling or grinding;
- based on the condition of the edges – with trimmed edges and ends or, at the client's request, with mechanically treated edges and ends.
Rolled stock dimensions and norms for maximum dimension deviations meet ASTM B 386 standards.
Maximum deviations for thickness of Мo99.95-PM brand rolled stock
Width, mm | Thickness, mm | Maximum thickness deviation |
305 or less | from 0.3 to 0.51 | ± 0,05 mm |
> 0,51 | ± 10 % | |
from 305 to 610 | > 0,64 | ± 10 % |
The thickness of rolled stock ranges from 0.3 (0.2) to 45 mm. Maximum width deviations are set based on agreement with the consumer, but do not exceed ±1.6 mm for trimmed sheets and ±0.8 mm for sheets with milled edges.
Maximum widths and lengths of thick sheets and mechanically treated plates prepared from them with a thickness of between 6 and 45 mm are set based on an agreement with the client, depending on his requests (plans).
Sample dimensions for Mo99.95-PM large-size plates and sheets:
- 8х127х1575 mm;
- 8х400х800 mm;
- 10х305х1000 mm;
- 12х609х609 mm;
- 12х190х1470 mm;
- 16х610х710 mm;
- 18х244х1010 mm;
- 42х83х107 mm;
- 45х95х110 mm.
Maximum length and camber deviations do not exceed ±1.6 mm for a length of 304.8 mm, unless otherwise requested.
Maximum flatness (waviness) deviations for Mo99.95-PM rolled stock:
- < 4% for thicknesses from 0.3 to 4.75 mm;
- < 5% for thicknesses from 4.75 to 12.7 mm;
Surface condition: rolled stock is delivered without cracks, slivers, backfins, rolled-in foreign particles, or blemishes.
Guaranteed mechanical properties of Мo99.95-PM rolled stock*
Thickness, mm | Durability σв, Н/mm2 (kgf/mm2 | Relative elongation δ, % |
At least | ||
from 0.33 to 0.5 | 760 (77) | 6 |
from 0.5 to 1.5 | 725 (74) | 10 |
from 1.5 to 2.5 | 690 (70) | 14 |
from 2.5 to 4.75 | 690 (70) | 18 |
from 4.75 to 12.7 | 690 (70) | 10 |
from 12.7 to 25.4 | 655 (67) | 2** |
from 25.4 to 38 | 655 (67) | 1** |
*property norms are established for materials after annealment in a protective atmosphere at a temperature of 900 оС during a 30 minute period
**parameters are determined using samples transverse to the direction of the rolling
Thin sheets with a thickness of less than 1 mm should withstand a bending test to an ordered angle of at least 90о.
Sample values for mechanical properties of molybdenum rolling stock
Thickness, mm | Durability σв, kgf/mm2 | Relative elongation δ, % | Hardness НВ |
1,0-1,3 | 78-85 |
13-16 |
217-240 |
1,9-2,5 | 79-88 | 18-21 | 229-240 |
3,0-5,4 | 75-82 | 18-25 | 210-229 |
Microstructure
The manufacturer monitors the microstructure of rolled sheets. In thin sheets (less than 4.75 mm), no full recrystallization structure is permitted, unless otherwise requested by the client.
*Fig.3: Sample structure of molybdenum sheet with a thicknes of 0.5 mm, transverse, x100, following bending tests.