CN105803253A

CN105803253A - Production process of alloy for producing high-power power generator rotor slot wedge

Info

Publication number: CN105803253A
Application number: CN201610401755.1A
Authority: CN
Inventors: 李国升
Original assignee: Pingdingshan Power Supply Co of State Grid Henan Electric Power Co Ltd
Current assignee: Pingdingshan Power Supply Co of State Grid Henan Electric Power Co Ltd
Priority date: 2013-11-29
Filing date: 2013-11-29
Publication date: 2016-07-27
Anticipated expiration: 2033-11-29
Also published as: CN105925838B; CN105803253B; CN103643079B; CN105925838A; CN103643079A

Abstract

The invention discloses a production process of an alloy for producing a high-power power generator rotor slot wedge. The alloy comprises 2.4-2.6 Wt% of Ni, 0.36-0.40 Wt% of Cr, 0.60-0.65 Wt% of Si, 0.02-0.03 Wt% of P and the balance of Cu. The production process includes steps of smelting, casting, solid solution treatment and age strengthening. Through ingredient proportion controlling, process optimizing and multiphase strengthening, conductivity of the obtained alloy is 62-65% IACS; at temperature below 500 DEG C, tensile strength is 689-692 MPa, and yield strength is 644-647 MPa. The alloy is high in conductivity, good in resistance to high temperature, long in service life, capable of meeting requirements on using for the high-power power generator rotor slot wedge, simple, low in production cost, little in environment pollution and good in market prospect and economic benefit.

Description

A kind of production technology producing high-power generator rotor slot wedge alloy

Technical field

The invention belongs to generator amature slot wedge material production technical field, be specifically related to a kind of production technology producing high-power generator rotor slot wedge alloy.

Background technology

Generator amature slot wedge to bear copper cash, insulating part and self huge centrifugal force in rotor operating time slot, and electric current flows through slot wedge can produce higher temperature rise, needs to use the alloy material that conductivity is high, resistance to elevated temperatures is excellent when producing rotor slot wedge.

Application number is that in the patent " large-capacity steam turbine generator rotor copper alloy slot wedge and preparation method thereof " of 200510123011, alloying component is: Ni:1.35～2.05%, Si:0.40～0.80%, Cr:0.05～0.25%, Be:0.15～0.40%, Cu: surplus；Production technology mainly adopts 920～980 DEG C of solution treatment, 35～50% cold deformations, 450～500 DEG C of insulation 4～5h Ageing Treatment, air cooling.In this technical scheme, Be price is high, and affects the high-temperature stability of alloy, makes alloy should not bear hot operation for a long time, and the dust of the alloy generation simultaneously adding Be can be poisonous；In alloy, the quality proportioning of Ni, Si is about 2.5～3.5, and Si content is relatively higher, and only some Si forms Ni₂Si precipitated phase, remaining Si exists with solid solution state, has a strong impact on the conductivity of alloy；Gained alloy conductive rate is only 49%IACS, and the life-span is short, and resistance to elevated temperatures is unknown.Application number is in the patent " titan bronze for slot wedge on turbo generator rotor and processing technique thereof " of 200510038051.4, titan bronze adopts and designs without zirconium without cobalt, its composition is: Be:0.1～0.3%, Ni:1.5～2.5%, Ti:0.4～0.6%, Cu: surplus, gained alloy conductive rate is only 47%IACS, high temperature (427 DEG C) yield strength 480～550MPa, tensile strength 540～630MPa, working life is short, it is impossible to meet the demand of high-power generator long time running.

Summary of the invention

The present invention is to make up above-mentioned deficiency, and composition proportion and production technology are improved, thering is provided a kind of production technology producing high-power generator rotor slot wedge alloy, this alloy conductive rate is high, and resistance to elevated temperatures is good, life-span is long, meeting the instructions for use of high-power generator rotor slot wedge alloy, technique is simple simultaneously, and production cost is low, environmental pollution is little, has good market prospect and economic benefit.

A kind of production technology producing high-power generator rotor slot wedge alloy, the composition of described alloy and content (Wt%) thereof including: Ni2.4～2.6, Cr0.36～0.40, Si0.60～0.65, P0.02～0.03, Cu: surplus；Comprise the following steps:

1. melting: first cathode copper is preheated to 250～280 DEG C, reinstall in Ajax-Wyatt furnace, coverture is added when starting to melt, make cladding thickness reach 1.2～1.4mm, all add the phosphor-copper accounting for copper mass 0.5～0.7% after fusing as deoxidizer, skim, after supplementing coverture, considering the physicochemical property of each element, Si, P, Ni, Cr technique routinely added according to this in copper melts, insulation 15min comes out of the stove；

2. casting: adopt conventional continuous casting process, hydraulic press forges into base；

3. solution treatment: heat treatment 1.5h carries out Water Quenching again at 940～960 DEG C, cold rolling makes alloy produce 60% cold deformation；

4. ageing strengthening: after again strand heating being incubated 2.5h to 460～480 DEG C, be machined into required form；The composition of described coverture and content (Wt%) thereof is: 50% Linesless charcoal, 30% cullet, 10%NaCl, 10%CaF₂。

In the technical program, in composition proportion, Cr can put forward heavy alloyed electrical conductance, forms Cr₃Si phase affects the high-temperature stability of alloy, and can suppress the grain growth of alloy during solution treatment to a certain extent；Because Be and Ni in cuprio₂Si has similar mechanical performance, therefore, can properly increase Ni₂The content of Si, obtain better heat stability and elevated temperature strength, the weight/mass percentage composition of proportioning Ni and Si is respectively 2.2～2.6%, 0.55～0.65%, avoid in alloy containing solid solution state Si, thus improve intensity and the conductivity of alloy, both guarantee the performance of alloy, reduced production cost, decrease again pollution；And after adding Cr, Cr will be first dissolved in Cu than Ni, Si, have the substrate at saturation, improve Ni to a certain extent₂The amount of precipitation of Si phase, in matrix, Ni, Si content reduces, and decreases the degree of distortion of lattice in matrix, improves the conductivity of alloy；Make alloy contain P that weight/mass percentage composition is 0.02～0.03%, it is in order to alloy will not be made to produce on the basis of obvious distortion of lattice, produce Ni3P precipitation phase, put forward heavy alloyed microhardness and tensile strength further, and suppress growing up of precipitated phase to a certain extent, making alloy substrate obtain purification, conductivity improves.

During alloy melting, Ajax-Wyatt furnace is selected to reduce the melting consumption of copper alloy, first preheat before in cathode copper addition stove, Si, P, Ni, Cr are melted in order, rational shove charge and fusing order shorten fusing time effectively, and coverture quality proportioning selects 50% Linesless charcoal, 30% cullet, 10%NaCl, 10%CaF₂, this coverture spreadability is good, can cover liquid metal bath surface during alloy melting comprehensively, strong with the affinity of slag, has the fabulous ability purifying liquid metal, refining alloy, makes melt suitably be protected and obtain preferably melting atmosphere；The phosphor-copper of addition 0.5～0.7% is as deoxidizer, it is possible to effectively removes the oxygen particle in melt, is effectively improved quality and the yield rate of alloy.

Strand adopts the admittedly molten Quenching Treatment of high temperature, aging of middle temperature process the method precipitating out precipitation hardening alloy, and the method production technology is simple, it is simple to alloy is convenient for large-scale production.Treatment temperature during solution treatment does not produce premised on coarse grains by alloy, improves temperature, rapid cooling after held for some time, it is ensured that the solute element of precipitated phase reaches maximum solid solubility in the base as far as possible.When at 940～960 DEG C, heat treatment 1.5h carries out Water Quenching again, excessive phased soln, obtain supersaturated solid solution, the cold rolling cold deformation making alloy generation bigger, alloy substrate generation recrystallization, intrinsic silicon is made to produce a large amount of dislocations, the substructure of alloy is refined, but this working hardening is limited to the intensity contribution of copper alloy, needing Ageing Treatment to strengthen further, be incubated the Ageing Treatment of 2.5h through 460～480 DEG C, alloying element is the precipitated phase phase of Dispersed precipitate, and precipitation hardened, alloy is made to obtain best performance.

The technical program is on the basis of common process, by optimizing multicomponent alloy composition, adding trace element, control composition proportioning to put forward heavy alloyed intensity, and it is avoided as much as or reduces the harmful effect of alloy conductivity, carrying out heterogeneous strengthening, gained alloy material, under room temperature, tensile strength 796～798MPa, yield strength 734～737MPa, elongation 17.9～18.2%, conductivity 62～65%IACS；At 500 DEG C, tensile strength 689～692MPa, yield strength 644～647MPa, conductivity is high, and resistance to elevated temperatures is good, and the life-span is long, it is ensured that the security reliability of high-power generator.Meeting the instructions for use of high-power generator rotor slot wedge alloy, significantly improve the security reliability of high-power generator, technique is simple simultaneously, and production cost is low, and environmental pollution is little, has good market prospect and economic benefit.

Specific embodiment

Embodiment one

A kind of high-power generator rotor slot wedge alloy of preparation, composition and the content (Wt%) thereof of each combination gold include: 2.2%Ni, 0.32%Cr, 0.55%Si, 0.02%P, Cu: surplus；

The production technology of described high-power generator rotor slot wedge alloy, comprises the following steps:

1. melting: first cathode copper is preheated to 250 DEG C, reinstalls in Ajax-Wyatt furnace, adds coverture when starting to melt, coverture mass component includes 50% Linesless charcoal, 30% cullet, 10%NaCl, 10%CaF₂, make cladding thickness reach 1.2mm, all add the phosphor-copper accounting for copper mass 0.5% after fusing as deoxidizer, skim, after supplementing coverture, consider the physicochemical property of each element, Si, P, Ni, Be, Cr technique routinely being added according to this in copper melts, insulation 15min comes out of the stove；

3. solution treatment: heat treatment 1.5h carries out Water Quenching again at 940 DEG C, cold rolling makes alloy produce 60% cold deformation；

4. ageing strengthening: after again strand heating being incubated 2.5h to 460 DEG C, be machined into required form.

After testing, alloy property is as shown in the table:

Embodiment two

A kind of high-power generator rotor slot wedge alloy of preparation, composition and the content (Wt%) thereof of each combination gold include: 2.4%Ni, 0.36%Cr, 0.60%Si, 0.03%P, Cu: surplus；

1. melting: first cathode copper is preheated to 265 DEG C, reinstalls in Ajax-Wyatt furnace, adds coverture when starting to melt, coverture mass component includes 50% Linesless charcoal, 30% cullet, 10%NaCl, 10%CaF₂, make cladding thickness reach 1.3mm, all add the phosphor-copper accounting for copper mass 0.6% after fusing as deoxidizer, skim, after supplementing coverture, consider the physicochemical property of each element, Si, P, Ni, Be, Cr technique routinely being added according to this in copper melts, insulation 15min comes out of the stove；

3. solution treatment: heat treatment 1.5h carries out Water Quenching again at 950 DEG C, cold rolling makes alloy produce 60% cold deformation；

4. ageing strengthening: after again strand heating being incubated 2.5h to 470 DEG C, be machined into required form.

After testing, alloy property is as shown in the table:

Embodiment three

A kind of high-power generator rotor slot wedge alloy of preparation, composition and the content (Wt%) thereof of each combination gold include: 2.6%Ni, 0.40%Cr, 0.65%Si, 0.03%P, Cu: surplus；

1. melting: first cathode copper is preheated to 280 DEG C, reinstalls in Ajax-Wyatt furnace, adds coverture when starting to melt, coverture mass component includes 50% Linesless charcoal, 30% cullet, 10%NaCl, 10%CaF₂, make cladding thickness reach 1.4mm, all add the phosphor-copper accounting for copper mass 0.7% after fusing as deoxidizer, skim, after supplementing coverture, consider the physicochemical property of each element, Si, P, Ni, Be, Cr technique routinely being added according to this in copper melts, insulation 15min comes out of the stove；

3. solution treatment: heat treatment 1.5h carries out Water Quenching again at 960 DEG C, cold rolling makes alloy produce 60% cold deformation；

4. ageing strengthening: after again strand heating being incubated 2.5h to 480 DEG C, be machined into required form.

After testing, alloy property is as shown in the table:

Shown by above three embodiment, employing the technical program, gained alloy material, under room temperature, tensile strength 796～798MPa, yield strength 734～737MPa, elongation 17.9～18.2%, conductivity 62～65%IACS；At 500 DEG C, tensile strength 689～692MPa, yield strength 644～647MPa, conductivity is high, and resistance to elevated temperatures is good, and the life-span is long, can meet the instructions for use of high-power generator rotor slot wedge alloy, it is ensured that the security reliability of high-power generator.

Claims

1. produce a production technology for high-power generator rotor slot wedge alloy, the composition of described alloy and content (Wt%) thereof to include: Ni2.4～2.6, Cr0.36～0.40, Si0.60～0.65, P0.02～0.03, Cu: surplus；It is characterized in that, comprise the following steps: