CN108193077A - Cu-Fe-C alloys - Google Patents

Cu-Fe-C alloys Download PDF

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Publication number
CN108193077A
CN108193077A CN201810259093.8A CN201810259093A CN108193077A CN 108193077 A CN108193077 A CN 108193077A CN 201810259093 A CN201810259093 A CN 201810259093A CN 108193077 A CN108193077 A CN 108193077A
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powder
raw material
alloy
alloys
sintering
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CN108193077B (en
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许磊
王海燕
邓小玲
历长云
胡号
王亚松
米国发
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Henan University of Technology
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Henan University of Technology
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    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C9/00Alloys based on copper
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C1/00Making non-ferrous alloys
    • C22C1/04Making non-ferrous alloys by powder metallurgy
    • C22C1/0425Copper-based alloys

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)

Abstract

The present invention provides a kind of Cu Fe C alloys, is prepared by following steps:(1) prepare raw material:The raw material includes pure Cu powder and Fe C prealloy powder, (2) ball milling mixing:It adds in abrading-ball and carries out mixed powder, obtain composite powder, (3) hot pressed sintering:The composite powder obtained in the step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature is 800~1000 DEG C, and sintering pressure is 45~55MPa, and sintering time is 30min~45min, obtains Cu Fe C alloys.The present invention can improve the conductivity and tensile strength of Cu Fe alloys.

Description

Cu-Fe-C alloys
Technical field
The present invention relates to composite materials to lead field, more particularly to a kind of Cu-Fe-C alloys.
Background technology
Compared with the copper alloy with high strength and high conductivity of other systems, the fusing point of alloying element Fe is relatively low in Cu-Fe systems, is easier to Melting, and non-miscible gap of Fe and Cu is small, the deformability of alloy is preferable, and machinability is preferable, so being closed about Cu-Fe systems The research of gold receives attention, becomes one of the important directions of copper alloy with high strength and high conductivity development.
At present, high-strength highly-conductive Cu-Fe systems alloy mainly prepares just alloy using fusion casting, then first alloy is carried out follow-up The processing such as heat treatment, deformation, obtain the Cu-Fe systems alloy of final use state.When founding prepares just alloy, due to solidification Cooling velocity is very fast, it is easy to cause to be dissolved a large amount of Fe elements in Cu matrixes, the serious electric conductivity for reducing Cu-Fe alloys.Though So oversaturated Fe is constantly precipitated during subsequent heat treatment, thermomechanical treatment etc., but under low temperature Fe diffusion velocity it is very slow, It is difficult to the Fe being dissolved in Cu is precipitated completely, and solid solutions of the Fe in Cu is to reduce the main influence factor of Cu-Fe alloys.Institute In order to improve the electric conductivity of Cu-Fe alloys, to need to reduce solid solution capacities of the Fe in Cu.
In the prior art frequently with deformation, heat treatment, high-intensity magnetic field, it is multi-element alloyed the methods of, but cannot all solve well Certainly this problem.Such as:Ag is considered as to damage the minimum element of Cu alloy conductives effect, but utilizes Ag to Cu-Fe alloys The Cu-Fe-Ag alloys of alloying preparation are carried out, but more than 2.5% Fe is still dissolved in its as cast condition Cu matrixes;And Ag also drops The low stability of Fe phase fibers, causes Fe phases to be roughened at 350 DEG C or more, reduces the use temperature range for limiting alloy;And It is and higher using Ag alloying costs.The Fe being dissolved in Cu can not be equally reduced to very low state by other methods.
In order to more effectively reduce the Fe being dissolved in Cu, it is necessary to provide a kind of Fe-Cu-C alloys.
Invention content
The purpose of the present invention is to provide a kind of Cu-Fe-C alloys, can efficiently reduce the Fe being dissolved in Cu-, improve The electric conductivity of Cu-Fe alloys, also improves the stability of Fe phase fibers, Fe phases will not be caused to be roughened at 350 DEG C or more, carried The high use temperature range of alloy, and reduce the manufacturing cost of alloy.
To achieve these goals, the present invention provides following technical solution:
A kind of Cu-Fe-C alloys, Cu-Fe-C alloys are prepared by following steps:
(1) prepare raw material:Raw material includes pure Cu powder and Fe-C prealloy powder,
(2) ball milling mixing:It adds in abrading-ball and carries out powder mixing machine, obtain composite powder,
(3) hot pressed sintering:The composite powder obtained in step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature Spend for 800~1000 DEG C (such as 820 DEG C, 830 DEG C, 840 DEG C, 850 DEG C, 860 DEG C, 870 DEG C, 880 DEG C, 890 DEG C, 900 DEG C, 910 DEG C, 920 DEG C, 930 DEG C, 940 DEG C, 950 DEG C, 960 DEG C, 970 DEG C, 980 DEG C, 990 DEG C), sintering pressure for 45~55MPa (such as 46MPa, 47MPa, 48MPa, 49MPa, 50MPa, 51MPa, 52MPa, 53MPa, 54MPa), sintering time is 30min~45min (such as 31min, 32min, 33min, 34min, 35min, 36min, 37min, 38min, 39min, 40min, 41min, 42min, 43min, 44min),
Obtain the Cu-Fe-C alloys of Fe-C even particle distributions.
The Cu-Fe-C alloys prepared by above-mentioned steps are a kind of novel high-strength highly-conductive Cu alloys, and C is utilized and Cu exists Mutually exclusive effect in Fe-Cu-C ternary systems, therefore C is added into Cu, and for this effect for giving full play to C, Cu-Fe-C alloys are prepared using Cu powder, Fe-C prealloy powder hot pressed sintering.The tensile strength of Cu-Fe-C alloys obtained is 560 ~640MPa, conductivity are 54~62%IACS.
In the alloy of the present invention, as a kind of preferred embodiment, the grain size of pure Cu powder is 10~50 μm.Pure Cu powder When grain size is 10~50 μm, Fe-C particles can be more evenly distributed in Cu matrixes.The size of Fe-C prealloy powder for 50~ 120nm (such as 60nm, 70nm, 80nm, 90nm, 100nm, 50nm~70nm, 60~80nm, 70~80nm, 80~100nm, 100~120nm).The Fe-C alloyed powders are commercial product, naturally it is also possible to conventionally prepare, it can be by true Prepared by empty atomizing furnace, will be atomized into powder particle after the pure iron as raw material of required proportioning and carburant melting, then pass through high energy again Ball milling is prepared into the Fe-C alloyed powders of required granularity.The Fe-C alloyed powders particle size used in the present invention is 50~120nm, Fe-C alloy powder particles it is oversized, disperse can be caused so cause precipitation strength effect reduction;Fe-C alloy powder particles It is undersized, easily Fe is made to be dissolved in Cu, electric conductivity is deteriorated, and is also easy to reunite.
Further, the size of Fe-C prealloy powder is 60~80nm.In the reasonable scope, the size of Fe-C prealloy powder Smaller, dispersion-strengthened action is bigger, but its surface can be bigger simultaneously, is dissolved in the easier matrix to Cu.
In the alloy of the present invention, as a kind of preferred embodiment, raw material includes pure Cu powder and Fe-C prealloy powder, institute The 85-90wt% (such as 86%, 87%, 88%, 89%) that pure Cu powder accounts for the raw material is stated, the Fe-C prealloy powder accounts for described The 10-15wt% of raw material such as 11%, 12%, 13%, 14%).
In the alloy of the present invention, as a kind of preferred embodiment, the C in the Fe-C prealloy powder accounts for the pre- conjunction Bronze 0.8-1.8wt% (such as:0.9wt%, 1.0wt%, 1.1wt%, 1.2wt%, 1.3wt%, 1.4wt%, 1.5wt%, 1.6wt%, 1.7wt%).
In the alloy of the present invention, C content is too low will to lead to have more Fe to dissolve in Cu, to the electric conductivity of alloy not Profit, C content is excessively high to form graphite or Fe3C。
In the step of preparing alloy of the present invention, as a kind of preferred embodiment, alloy post-processing step is further included, it will The Cu-Fe-C systems alloy that (3) the hot pressed sintering step obtains is post-processed, and obtains Cu-Fe-C systems alloy finished product.More preferably Ground, the post processing are one or more in heat treatment, deformation process, magnetic field processing;The post processing is conventional treatment.
Analysis is it is found that a kind of Cu-Fe-C alloys disclosed by the invention, mainly realize following technique effect:Utilize C and Cu Mutually exclusive effect in Fe-Cu-C ternary systems, therefore C is added into Cu, and for this work for giving full play to C With, using Cu powder, Fe-C prealloy powder hot pressed sintering prepare Cu-Fe-C alloys, have developed novel high-strength highly-conductive Cu alloys.
Diffusions of the Fe into Cu matrixes is controlled, the solid solution capacity of Fe in Cu matrixes is greatly reduced.The method of the present invention can improve The conductivity and tensile strength of Cu-Fe alloys, the tensile strength of obtained alloy are more than 560MPa, conductivity 54-62% IACS。
Specific embodiment
Below in conjunction with embodiment, the present invention will be described in detail.Each example the present invention explanation by way of provide and The unrestricted present invention.In fact, those skilled in the art will be clear that, in the situation for not departing from the scope or spirit of the invention Under, it can modify in the present invention and modification.For example, the feature for being illustrated or described as the part of one embodiment can be used for Another embodiment, to generate another embodiment.Thus, it may be desirable to the present invention comprising be included into appended claims and Such modifications and variations in the range of its equivalent.
Embodiment 1
(1) prepare raw material:The Fe-1.2wt%C that raw material includes 10~50 μm of pure Cu powder and size is 70~120nm is pre- Alloyed powder, the mass percent of C is 1.2wt% in Fe-C alloy powders, and pure Cu powder accounts for the 89wt% of the raw material, and Fe-C is closed in advance Bronze accounts for the 11wt% of the raw material,
(2) ball milling mixing:It adds in abrading-ball and carries out powder mixing machine, obtain composite powder,
(3) hot pressed sintering:The composite powder obtained in step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature It is 900 DEG C, sintering pressure 50MPa, sintering time 30min to spend,
Cu-11wt% (Fe-C) alloy of Fe-1.2wt%C even particle distributions must have been prepared.
The alloy prepared to the embodiment is tested for the property, and the tensile strength of alloy is 580MPa, and conductivity is 60.8%IACS.
Embodiment 2
(1) prepare raw material:The Fe-1.0wt%C that raw material includes 10~50 μm of pure Cu powder and size is 70~120nm is pre- Alloyed powder, the mass percent of C is 1.0wt% in Fe-C alloy powders, and pure Cu powder accounts for the 85wt% of the raw material, and Fe-C is closed in advance Bronze accounts for the 15wt% of the raw material,
(2) ball milling mixing:It adds in abrading-ball and carries out powder mixing machine, obtain composite powder,
(3) hot pressed sintering:The composite powder obtained in step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature It is 800 DEG C, sintering pressure 50MPa, sintering time 30min to spend,
Cu-15wt% (Fe-C) alloy of Fe-1.0wt%C even particle distributions must have been prepared.
The alloy prepared to the embodiment is tested for the property, and the tensile strength of alloy is 636MPa, and conductivity is 54.1%IACS.
Embodiment 3
(1) prepare raw material:The Fe-1.1wt%C that raw material includes 10~50 μm of pure Cu powder and size is 50~80nm is closed in advance Bronze, the mass percent of C is 1.1wt% in Fe-C alloy powders, and pure Cu powder accounts for the 87wt% of the raw material, Fe-C prealloys Powder accounts for the 13wt% of the raw material,
(2) ball milling mixing:It adds in abrading-ball and carries out powder mixing machine, obtain composite powder,
(3) hot pressed sintering:The composite powder obtained in step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature It is 820 DEG C, sintering pressure 50MPa, sintering time 30min to spend,
Cu-13wt% (Fe-C) alloy of Fe-1.1wt%C even particle distributions must have been prepared.
The alloy prepared to the embodiment is tested for the property, and the tensile strength of alloy is 628MPa, and conductivity is 55.6%IACS.
Embodiment 4
(1) prepare raw material:The Fe-1.1wt%C that raw material includes 10~50 μm of pure Cu powder and size is 50~80nm is closed in advance Bronze, the mass percent of C is 1.1wt% in Fe-C alloy powders, and pure Cu powder accounts for the 90wt% of the raw material, Fe-C prealloys Powder accounts for the 10wt% of the raw material,
(2) ball milling mixing:It adds in abrading-ball and carries out powder mixing machine, obtain composite powder,
(3) hot pressed sintering:The composite powder obtained in step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature It is 820 DEG C, sintering pressure 50MPa, sintering time 30min to spend,
Cu-10wt% (Fe-C) alloy of Fe-1.1wt%C even particle distributions must have been prepared.
The alloy prepared to the embodiment is tested for the property, and the tensile strength of alloy is 573MPa, and conductivity is 57.2%IACS.
Embodiment 5
(1) prepare raw material:The Fe-1.1wt%C that raw material includes 10~50 μm of pure Cu powder and size is 50~80nm is closed in advance Bronze, the mass percent of C is 1.1wt% in Fe-C alloy powders, and pure Cu powder accounts for the 89wt% of the raw material, Fe-C prealloys Powder accounts for the 11wt% of the raw material,
(2) ball milling mixing:It adds in abrading-ball and carries out powder mixing machine, obtain composite powder,
(3) hot pressed sintering:The composite powder obtained in step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature It is 820 DEG C, sintering pressure 50MPa, sintering time 30min to spend,
Cu-11wt% (Fe-C) alloy of Fe-1.1wt%C even particle distributions, i.e., Fe-C in the alloy must have been prepared Content be 11wt%.
The alloy prepared to the embodiment is tested for the property, and the tensile strength of alloy is 585MPa, conductivity 61% IACS。
Embodiment 6
(1) prepare raw material:The Fe-1.1wt%C that raw material includes 10~50 μm of pure Cu powder and size is 60~80nm is closed in advance Bronze, the mass percent of C is 1.1wt% in Fe-C alloy powders, and pure Cu powder accounts for the 88wt% of the raw material, Fe-C prealloys Powder accounts for the 12wt% of the raw material,
(2) ball milling mixing:It adds in abrading-ball and carries out powder mixing machine, obtain composite powder,
(3) hot pressed sintering:The composite powder obtained in step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature It is 820 DEG C, sintering pressure 50MPa, sintering time 30min to spend,
Cu-12wt% (Fe-C) alloy of Fe-1.1wt%C even particle distributions must have been prepared.
The alloy prepared to the embodiment is tested for the property, and the tensile strength of alloy is 615MPa, and conductivity is 54.8%IACS.
Embodiment 7-12 and comparative example 1-2
Embodiment 7-12 and comparative example 1-2 in addition to raw material proportioning and raw material granularity are different from embodiment 1, other techniques with Embodiment 1 is identical.The raw material dosage relationship of embodiment 7-12 and comparative example 1-2 and raw material granularity referring to table 1, corresponding embodiment and The performance test results of alloy prepared by comparative example are referring to table 1.As can be seen from Table 1, (tension is strong for the performance of embodiment 8,9,10 Degree and conductivity) significantly better than comparative example 1,2 and embodiment 7,11,12.
The raw material dosage relationship and raw material granularity of table 1 embodiment 7-12 and comparative example 1-2 and corresponding product performance table
Embodiment 13-17
For embodiment 13-17 in addition to hot pressed sintering is different from embodiment 1, other techniques are same as Example 1.Embodiment The performance test results for the alloy product that the hot pressed sintering of 13-17 is obtained referring to table 2, corresponding embodiment and comparative example are referring to table 2. As can be seen from Table 2, the performance (tensile strength and conductivity) of embodiment 13,14,15 is significantly better than embodiment 16,17.
The stirring condition and properties of product table of 2 embodiment 13-17 of table

Claims (10)

1. a kind of Cu-Fe-C alloys, which is characterized in that the Cu-Fe-C alloys are prepared by following steps:
(1) prepare raw material:The raw material includes pure Cu powder and Fe-C prealloy powder,
(2) ball milling mixing:It adds in abrading-ball and carries out powder mixing machine, obtain composite powder,
(3) hot pressed sintering:The composite powder obtained in the step (2) is put into hot-pressed sintering furnace and is sintered, sintering temperature It is 800~1000 DEG C to spend, and sintering pressure is 45~55MPa, and sintering time is 30min~45min,
Obtain the Cu-Fe-C alloys of Fe-C even particle distributions.
2. alloy according to claim 1, which is characterized in that the grain size of the pure Cu powder is 10~50 μm.
3. alloy according to claim 1, which is characterized in that the size of the Fe-C prealloy powder is 50~120nm.
4. alloy according to claim 1, which is characterized in that the size of the Fe-C prealloy powder is 60~110nm.
5. alloy according to claim 1, which is characterized in that the size of the Fe-C prealloy powder is 60~80nm.
6. alloy according to claim 1, which is characterized in that the C content in the Fe-C prealloy powder is 0.8- 1.8wt%.
7. alloy according to claim 1, which is characterized in that the pure Cu powder accounts for the 85-90wt% of the raw material, described Fe-C prealloy powder accounts for the 10-15wt% of the raw material.
8. alloy according to claim 1, which is characterized in that the C in the Fe-C prealloy powder accounts for the prealloy powder 0.8~1.2wt%.
9. alloy according to claim 1, which is characterized in that C content in the Fe-C prealloy powder for 1.0~ 1.2wt%.
10. alloy according to claim 1, which is characterized in that C content in the Fe-C prealloy powder for 1.2~ 1.6wt%.
CN201810259093.8A 2018-03-27 2018-03-27 Cu-Fe-C alloy Expired - Fee Related CN108193077B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117604301A (en) * 2023-11-24 2024-02-27 河南理工大学 Preparation method of elastic refrigeration alloy

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Publication number Priority date Publication date Assignee Title
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CN105543534A (en) * 2015-12-18 2016-05-04 中国科学院兰州化学物理研究所 Copper-based pantograph sliding plate material and preparation method thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117604301A (en) * 2023-11-24 2024-02-27 河南理工大学 Preparation method of elastic refrigeration alloy

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