A processing technology for manganese-copper precision resistance alloy

Abstract

The present invention discloses a processing technology of a manganese-copper precision resistance alloy belonging to the field of material processing technology. In the process, the 6J13 alloy ingot is roughened at 800-850°C into an ingot, and then forged into a long rod at 600-700°C for secondary forging; the wire is pickled, dried and rolled; then short-term high-temperature annealing is performed at 700-800°C for 15 minutes; the wire is drawn and deformed into a round wire, and the surface is peeled and drawn into a thin wire, and the thin wire is subjected to medium-temperature vacuum annealing for 24 hours at / 550-650°C. The finished wire obtained by the process has extremely high stability and orderliness in its structure, ensuring that the Cu-Mn precision resistance alloy resistor has both high long-term stability (the annual change rate of resistance value is less than 1.5PPM / year) and low temperature drift coefficient (less than 20PPM / ℃).

Description

Technical Field

[0001] The invention belongs to the technical field of material processing, and in particular relates to a processing technology of a manganese-copper precision resistance alloy. Background Art

[0002] Precision resistor materials have high resistance stability, extremely low temperature drift coefficient and thermal electromotive force to copper, and are the key basic materials for manufacturing precision resistor components. Precision resistor materials include iron-based (Fe-Cr-Al series, etc.), copper-based (Cu-Mn-Ni series, Cu-Ni-Mn series, etc.), manganese-based (Mn-Cu series, Mn-Ni series, etc.) and nickel-based (Ni-Cr-Al series, Ni-Cr-Fe series, etc.). Among them, Cu-Mn series precision resistor alloys have low resistance, low temperature drift, low thermal electromotive force to copper and other properties, and are currently one of the most widely used precision resistor materials.

[0003] Copper-manganese precision resistor shunts are indispensable key components in sensing and control circuits and are widely used in smart meters, automotive circuits, 5G communications, artificial intelligence, consumer electronics and other fields. Precision resistor shunts are mainly used to accurately detect current signals in control circuits, and have extremely strict requirements on the stability of resistor materials and their temperature drift performance. Therefore, precision resistor alloys are essentially different from ordinary resistor materials, especially electrothermal alloys. The resistance temperature drift coefficient (also known as the temperature coefficient of resistance, TCR) is a key performance indicator of precision resistor materials. This indicator mainly examines the trend of resistivity fluctuations with temperature, and its influencing factors are the material's phonon resistance and internal "K-state".

[0004] Another key indicator of precision resistor alloys is the long-term stability of resistance, which is defined as the ratio of resistance fluctuations of precision resistors within one year. The main influencing factors include the degree of metal lattice distortion, the concentration of crystal defects, and grain boundary stability. Under the long-term impact of current, the internal lattice arrangement of precision resistor materials gradually tends to be regular and stable, so the total resistance decreases and tends to be stable.

[0005] For a long time, the long-term stability of resistance and temperature drift performance of Cu-Mn precision resistance alloys such as 6J13 cannot be coordinated and unified. Selecting a high final annealing temperature (above 700℃) can ensure the stability of the material structure and obtain high long-term stability of resistance, but it will inevitably lead to a sharp deterioration of the temperature drift coefficient of the alloy resistance. On the contrary, in order to pursue excellent temperature drift performance of the alloy, a lower annealing temperature must be selected, but at this time, satisfactory long-term stability of resistance cannot be obtained.

[0006] Based on the conflict between the above stability and temperature drift performance, it is urgent to propose a processing technology for Cu-Mn precision resistor alloys that has both of the above two properties. Summary of the invention

[0007] In order to solve the above problems, the present invention proposes a processing technology for manganese-copper precision resistance alloy, wherein the specific steps of the process are:

[0008] 1. A processing technology for manganese-copper precision resistance alloy, wherein the specific steps of the process are:

[0009] 1) The manganese copper precision resistance alloy ingot is roughened at 800-850℃ The ingot is then forged at 600-700℃ for a second time. Long pole;

[0010] The manganese-copper precision resistance alloy is 6J13 alloy;

[0011] 2) After pickling and drying, the long rod Long rod rolled Wire; then the wire is subjected to short-term high temperature annealing at 700-800°C for 15 minutes;

[0012] 3) After pickling and drying, the manganese copper precision resistance alloy wire Wire drawing deformation to Round wire, surface peeled The secondary wire is used to remove the surface oxidized manganese layer; then The secondary wire is drawn to The thin wire is finally subjected to medium-temperature vacuum annealing at a temperature of 550-650°C for 24 hours; finally, the manganese-copper precision resistance alloy finished wire is obtained.

[0013] In some preferred embodiments, in step 1), after the alloy is strictly calcined and recrystallized and forged, the manganese atoms in the copper matrix reach an optimal homogeneous solid solution state to ensure the stability of the material structure in all directions; the average grain size of the obtained manganese-copper precision resistance alloy long rod is less than 15.0 μm, the Mn element is uniformly distributed as a whole, the material resistance temperature drift coefficient is less than 30 PPM / °C, and the annual resistance change rate is less than 2.5 PPM / year.

[0014] In some preferred embodiments, the average grain size of the manganese-copper precision resistance alloy wire obtained in step 2) is less than 10.0 μm, and the dislocation crystal defects are basically gone; the material resistance temperature drift coefficient is less than 25 PPM / °C, and the annual change rate of resistance value is lower than 2.0 PPM / year.

[0015] Step 2) The middle and long rod is Rolled After the wire rod is subjected to a large deformation rolling with a processing rate of 93%, {112} <111> Texture, resulting in anisotropy of manganese atomic distribution; short-term high-temperature annealing for 15min at 750±50℃ effectively eliminates the anisotropy of texture and manganese atomic distribution in the copper matrix caused by large deformation rolling.

[0016] In some preferred embodiments, the average grain size of the finished wire is less than 8.0 μm, the annual change rate of resistance of the finished wire is less than 1.5 PPM / year, and the temperature drift coefficient is less than 20 PPM / °C.

[0017] After the finished wire is subjected to medium-temperature vacuum annealing at 550-650° C. for 24 hours, a completely recrystallized structure without subgrains, dislocations and dislocation cells is finally formed. At the same time, a relatively stable Cu and Mn ordered phase is formed in the structure of the finished wire, and the stability and order of the structure are further improved, which is beneficial to the improvement of the temperature coefficient of resistance of the material.

[0018] The beneficial effects of the present invention are:

[0019] 1. After strict calcination and recrystallization forging, the manganese atoms in the copper matrix of the manganese-copper precision resistance alloy reach the best homogeneous solid solution state, making the Mn element uniformly distributed as a whole, eliminating the Mn atom-rich area in the lattice, thereby avoiding the change of the intrinsic resistivity of the resistance material due to the homogenization migration of Mn atoms during long-term use, ensuring the stability of the resistance value of the resistance material, and the annual change rate of resistance value is less than 2.5PPM / year.

[0020] 2. Manganese copper precision resistance alloy is rolled with large deformation to form {112} in the wire. <111> The texture leads to the anisotropy of the distribution of manganese atoms; the short-term high-temperature annealing at 700-800℃ greatly improves the uniformity and stability of Mn atoms in the copper matrix, and further improves the stability of the structure and resistance of the Cu-Mn precision resistor alloy.

[0021] 3. After the final low-temperature annealing at 550-650℃, the finished manganese-copper precision resistance alloy wire obtains a fine and highly ordered microstructure, the annual change rate of resistance value is less than 1.5PPM / year, and the temperature drift coefficient is less than 20PPM / ℃.

[0022] In summary, the finished manganese-copper precision resistance alloy wire prepared by the process of the present invention has significantly improved Mn atomic distribution stability, uniformity and orderliness compared with the existing single annealing process, which is not only beneficial to the improvement of the material resistance temperature coefficient, but also ensures the long-term stability of the material resistance value. DETAILED DESCRIPTION

[0023] The present invention is further described in detail below in conjunction with specific embodiments:

[0024] Example 1

[0025] 1) The 6J13 precision resistance alloy ingot is roughened at 800-850℃. The ingot is then forged at 600-700℃ for a second time. Long pole.

[0026] 2) Forging blank obtained from step 1) Long rod rolled The wire is then annealed at 750°C for 15 min.

[0027] 3) After the wire treated in step 2) is pickled and dried, Wire drawing deformation to Round wire, surface peeled To remove the surface oxidized manganese layer; then The wire is drawn to The thin wire is finally subjected to medium-temperature vacuum annealing at 600°C for 24 hours.

[0028] The annual resistance change rate of the 6J13 alloy wire processed by this process is 1.3 PPM / year, and the temperature drift coefficient is 19.5 PPM / ° C. The technical effect caused by this embodiment is also applicable to other Cu-Mn series precision resistance alloys.

[0029] Example 2

[0030] 1) The 6J13 precision resistance alloy ingot is roughened at 800-850℃. The ingot is then forged at 600-700℃ for a second time. Long pole.

[0031] 2) Forging blank obtained from step 1) Long rod rolled The wire is then annealed at 750°C for 15 min.

[0032] 3) After the wire treated in step 2) is pickled and dried, Wire drawing deformation to Round wire, surface peeled To remove the surface oxidized manganese layer; then The wire is drawn to The thin wire is finally subjected to high temperature vacuum annealing at a temperature of 750°C for 24 hours.

[0033] The annual change rate of resistance of the 6J13 alloy wire processed by this process is 1.1 PPM / year, and the temperature drift coefficient is 85.2 PPM / ° C. The technical effect caused by this embodiment is also applicable to other Cu-Mn series precision resistance alloys.

[0034] Example 3

[0035] 1) The 6J13 precision resistance alloy ingot is roughened at 800-850℃. The ingot is then forged at 600-700℃ for a second time. Long pole.

[0036] 2) Forging blank obtained from step 1) Long rod rolled The wire is then annealed at 650°C for 15 min.

[0037] 3) After the wire treated in step 2) is pickled and dried, Wire drawing deformation to Round wire, surface peeled To remove the surface oxidized manganese layer; then The wire is drawn to The thin wire is finally subjected to medium-temperature vacuum annealing at a temperature of 600°C for 24 hours.

[0038] The annual resistance change rate of the 6J13 alloy wire processed by this process is 10.2 PPM / year, and the temperature drift coefficient is 18.6 PPM / ° C. The technical effect caused by this embodiment is also applicable to other Cu-Mn series precision resistor alloys.

Claims

1. A processing technology for manganese-copper precision resistance alloy, wherein: The specific steps of the process are: 1) The manganese copper precision resistance alloy ingot is roughened at 800-850℃ The ingot is then forged at 600-700℃ for a second time. Long pole; The manganese-copper precision resistance alloy is 6J13 alloy; 2) After pickling and drying, the long rod Long rod rolled Wire; then the wire is subjected to short-term high temperature annealing at 700-800°C for 15 minutes; 3) After pickling and drying, the manganese copper precision resistance alloy wire Wire drawing deformation to Round wire, surface peeled The secondary wire is used to remove the surface oxidized manganese layer; then The secondary wire is drawn to The thin wire is finally subjected to medium-temperature vacuum annealing at a temperature of 550-650°C for 24 hours; finally, the manganese-copper precision resistance alloy finished wire is obtained.

2. According to the processing technology of the manganese-copper precision resistance alloy as claimed in claim 1, wherein: The average grain size of the manganese-copper precision resistance alloy long rod obtained in step 1) is less than 15.0 μm, the Mn element is uniformly distributed as a whole, the material resistance temperature drift coefficient is less than 30 PPM / °C, and the annual change rate of resistance value is less than 2.5 PPM / year.

3. According to the processing technology of the manganese-copper precision resistance alloy as claimed in claim 1, wherein: The average grain size of the manganese-copper precision resistance alloy wire obtained in step 2) is less than 10.0 μm, and dislocation crystal defects are basically gone; the material resistance temperature drift coefficient is less than 25 PPM / °C, and the annual change rate of resistance value is less than 2.0 PPM / year.

4. The processing technology of the manganese-copper precision resistance alloy according to claim 1, wherein: The average grain size of the finished wire is less than 8.0 μm, the annual change rate of the resistance value of the finished wire is less than 1.5 PPM / year, and the temperature drift coefficient is less than 20 PPM / °C.

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