SU0.021.150-81 TU
CONTROL EXAMPLE |
0730
SU0.021.150−81 TU instead. PGZhK 0.021 002 TU MKP 20 |
These specifications apply to wire with a diameter of 500, 60 microns, made of MKR-20 alloy, obtained by powder metallurgy, intended for the manufacture of special-purpose devices.
An example of a conventional designation for a wire of the MKR-20 alloy with a diameter of 500 μm: wire of the MKR-20 grade Ø500 μm according to SU0.021.150−81 TU.
1. CLASSIFICATION AND VARIETY.
1.1. The wire is made from an alloy of molybdenum with rhenium. Characteristics of the brand and alloy: an alloy of molybdenum with 20% rhenium, alloyed with a silicon-alkali additive.
1.2. The wire diameter must meet the requirements of table 1.
Table 1.
Alloy grade | Nominal diameter, μm | Nominal mass of a piece with a length of 200 mm, mg. | Permissible deviations of the diameter from the nominal value,% | Permissible deviations of the mass of a 200 mm segment from the nominal value,%. |
MKR-20 | 500 | - | ± 2.5 | - |
60 | 5.85 | - | ± 3.0 |
2. TECHNICAL REQUIREMENTS
2.1. The chemical composition of the wire must meet the requirements of Table 2.
Table 2.
Alloy grade | Molybdenum content,%, not less | Rhenium content,%. | Silicon content,% | The amount of impurities,%, no more |
MKR-20 | 80 ± 1 | 20 ± 1 | 0.014−0.04 | 0.04 |
Note: The amount of impurities includes
the following elements: calcium,
magnesium, nickel, iron, aluminum.
2.2. The mechanical properties of the wire must meet the requirements given in table 3.
Table 3.
Alloy grade | Wire diameter, μm | Tensile strength, kgf / , not less |
Elongation,%, not less |
MKR-20 | 500 | 230.0 | 3.0 |
2.3. A wire with a diameter of 500 microns must withstand at least 3 bends without breaking.
2.4. The wire with a diameter of 500 microns should not have cracks and delamination revealed by visual inspection.
The presence of discontinuities with a total length of not more than 10% of the total length of the wire in the coil is allowed during defectoscopic testing of the wire.
2.5. Wire color should be black to light gray.
2.6. Wire with a diameter of 500 microns should be wound in coils. The coil diameter should be 200 mm. Each bay should be tied with soft wire in three or four places. The bay should not be twisted into a figure eight. Wire with a diameter of 60 microns should be wound in even rows (without knots and loops) on spools and should be easily unwound from them.
2.7. There should be one piece of wire on the spool or coil of the length specified in table 4.
Table 4.
Wire diameter, μm | Length, m, not less |
500 60 |
five 50 |
Note: Estimated weight of one meter of wire
Ø 500 μm 2.3 gr.
3. RULES OF ACCEPTANCE.
3.1. For a control check by the consumer of the quality of the wire supplied to him for compliance with the requirements of these TUs, the sampling rules and test methods specified in these TUs must be applied.
3.2. Checking for compliance with the requirements of clauses 2.2., 2.3., 2.4., 2.5., 2.6., 2.7. exposed wire Ø 500 µm from each coil.
3.3. Checking for compliance with the requirements of clauses 2.5., 2.6., 2.7. exposed wire Ø 60 μm.
3.4. Wire that does not meet the requirements of any of the listed items will not be supplied.
4. CONTROL METHODS.
4.1. The wire diameter of 500 µm (p. 1.2.) Is measured on three turns of the coil in two mutually perpendicular directions with any instrument providing the required measurement accuracy.
The diameter of the wire 60 μm is checked according to OST11.021.006−76 by weighing a piece of wire 200 mm long on a torsion balance with a carrying capacity of 10 mg. Weighing is carried out twice and the average value is taken.
4.2. The tensile properties of the wire (clause 2.2.) Are checked according to OST11.021.006.76.
4.3. The number of wire bends is determined according to OST11.021.006.76 with a wire tension of 0.5 kg on jaws with a radius of curvature of 1.5 mm.
4.4. The absence of cracks and delamination (clause 2.4.) In the wire is checked according to OST11.021.006.76.
4.5. The color of the wire (clause 2.5.) Is checked by visual inspection of the top layer in the coil or on the coil.
4.6. The chemical composition of the wire (clause 2.1.) Is guaranteed by the manufacturer by controlling the technology (the analysis of a mixture of molybdenum powders with rhenium is made from each production batch for the content of rhenium according to the method of Appendix 1 and the initial semi-finished products — molybdenum powder and ammonium perrhenate) for the content of silicon and impurities according to GOST 14316−74 and OST 48−27.2−79. The content of impurities in the alloy is taken as the sum of their content in molybdenum powder and ammonium perrhenate.
Note: A production batch is an alloy,
obtained from a mixture of powders, at the same time
mixed in a mixer.
4.7. The number of sections, the length of the wire on the spool and in the coil are guaranteed by the manufacturer.
5. LABELING, PACKAGING, TRANSPORTATION AND STORAGE.
5.1. Each coil or coil must be labeled with:
- product name, supplier’s stamp;
- alloy grade;
- production batch number;
- coil weight or coil footage, percentage of discontinuity;
- nominal wire diameter;
- tensile strength, in kgf / ;
- number of kinks;
- date of manufacture and TU number.
5.2. Wire spools are packed in a cardboard box. Empty spaces in the box are filled with cardboard.
5.3. Wire coils are packed in moisture-proof paper in accordance with GOST 8828−61 .
Note: by agreement of the parties, other
types of packaging for storage
wire without oxidation.
5.4. The wire should be transported only in the packaging specified in clauses 5.2., 5.3.
5.5. The wire should be stored in the packaging specified in clause 5.2. and p. 5.3., in a dry room, free from acid vapors and other oxidants.
TEST REPORT
foil-clad dielectric No.
Lot No. from
СФ grade GOST 10316−78 СД
No. | NAME | The magnitude of the indicators | Note | |
GOST requirement | according to the results | |||
1 2 4 3 five 6 7 eight |
Sheet sizes, mm Sheet thickness, mm Surface condition from the foil and dielectric side Surface condition under the foil Edge trim quality Resistant to molten solder. Solder temperature (260 ± 5) ° C, holding time not less than 20 s Resistant to high temperatures. Temperature (120 ± 5) ° C for 3 hours Peeling strength of foil from the base (for a strip width of 3 mm), N, not less: — in its original state |
The foil should not flake off from the base and there should be no swelling on it There should be no whitening, swelling, delamination on the foil surface 4.5 |
Conclusion: meets the requirements of GOST 10316−78 SD