CN106636563A - Multiple-unit control method and multiple-unit control device for reverse laser shot peening - Google Patents
Multiple-unit control method and multiple-unit control device for reverse laser shot peening Download PDFInfo
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- CN106636563A CN106636563A CN201610964052.XA CN201610964052A CN106636563A CN 106636563 A CN106636563 A CN 106636563A CN 201610964052 A CN201610964052 A CN 201610964052A CN 106636563 A CN106636563 A CN 106636563A
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/06—Surface hardening
- C21D1/09—Surface hardening by direct application of electrical or wave energy; by particle radiation
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- G—PHYSICS
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- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
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Abstract
The embodiment of the invention discloses a multiple-unit control method and a multiple-unit control device for reverse laser shot peening. The region area and impact depth of laser shot peening treatment are reasonably designed by virtue of the modification characteristic of a surface layer material generated through laser shot peening, and a laminated section is constructed to change the Young moduli of parts, thus the inherent frequency is changed, and the dual purposes of reinforcement and frequency modulation treatment are realized; moreover, modelling analysis is carried out through a mechanical model to optimize a sizing region and parameters with regard to the common problem of structure deformation in the laser shot peening treatment, and repair for the deformation of the parts is realized through reversely loading impact loads, thus the purpose of dimensional stability of the laser shot peening parts is achieved; and moreover, the multiple-unit control method and the multiple-unit control device are capable of meeting the various needs of rotating parts, and in particular, are suitable for high-speed rotating parts bearing aerodynamic loads, such as gas turbine blades, aviation engine blades and the like.
Description
Technical field
The present invention relates to laser peening field, more particularly to a kind of polynary control method of reverse laser peening and device.
Background technology
Due to the effect of centrifugal force and inertia force when high speed rotating part works, each particle bears alternate stress load in material
Lotus, although the stress that part is born is less than the yield point of material, but crackle or prominent is also easy to produce after the work of long period
So there is the fatigue failure ruptured completely.According to statistics, about more than 80% fatigue rupture is belonged in machine components failure, and
And without significantly deformation before fatigue rupture, so fatigue rupture often results in major accident, such as gas turbine stops, aircraft is sent out
Motivation flame-out in flight etc..Therefore, on the one hand bear the part of alternate load will select the preferable material of fatigue strength to manufacture, separately
On the one hand need to carry out material reinforcement process.
When gas turbine blades, blade of aviation engine high speed rotational operation, blade is to cause blade to shake with train resonance
The main cause of dynamic fatigue failure.Therefore there is strict demand to vibration frequency of blade：For example, the same grade blade of gas turbine is installed
Shi Bixu is by the control control of frequency dispersion degree within 8%.Again for example, aero-engine seaworthiness clause CCAR33.83 vibrations examination
Part regulation is tested, vibration stress analysis, vibration-mode analysis and vibration test must be carried out during blade design, adjusted
Frequently-resonance nargin analysis-modal test-dynamic stress rest and the experiment process assessed, it is ensured that under each working speed of blade altogether
Shake nargin >=10%, endurance percentage >=30%.Therefore, blade not only needs frequency modulation to process guarantee resonance nargin, and
Need intensive treatment to ensure dynamic stress nargin, make off-resonance frequence in the blade working range of speeds, meet projected life requirement.
In sum, revolution at a high speed part, especially blade need to carry out intensive treatment and frequency modulation is processed and could meet whole
Machine design requirement.It is a kind of surface intensified technique that at present widely used mechanic shot peening is processed, for improve part machinery intensity with
And wearability, antifatigue and corrosion resistance etc., but there is reinforcing dead angle in mechanic shot peening, and reinforcing effect randomness is unstable, work
The shortcomings of skill parameter more difficult formulation, it is difficult to the blade of intensive treatment complex contour.Current vane frequency modulation is mainly finely tuned using structure
Method changes barycenter or adjusts overall structure, and for example reinstalling blade improves installation quality, changes blade group number, leaf top brill
Degree of being connected firmly of hole, increase convex shoulder, adjustment blade and leaf dish etc., above control method is to be to change part quality/structure
Means, it is impossible to which from essence adjustment Natural Frequency of Blade, frequency offset is uncontrollable, it is difficult to process the high part of band requirement,
Such as aeroengine fan blades, compressor blade.
Therefore it provides one kind is based on Laser Peening Technology, realize that high speed rotating part material reinforcement, intrinsic frequency change
The control method and device for becoming and controlling the multiple elements design process of form factor is the problem that those skilled in the art need to solve.
The content of the invention
A kind of polynary control method of reverse laser peening and device are embodiments provided, existing high speed rotation is overcome
Turn reinforcing, frequency modulation and the nonsynchronous problem of school shape technique of part, and realized using laser peening reinforcing, frequency modulation and school shape ability
The polynary process of part, lift structure fatigue life, the resonance nargin ensured in part time job rotating speed.
A kind of polynary control method of reverse laser peening is embodiments provided, including：
S1：According to treat parts processed carry out laser peening reinforcing index that structural analysis and residual stress test obtain and
Technological parameter, determines the laser peening strengthening region of the pending part；
S2：Strengthen parameter according to preset laser peening carries out laser to the laser peening strengthening region of the pending part
Shot peening, the part after being strengthened；
S3：Part after the reinforcing is sampled and obtains specimen part, then fatigue life, residual is carried out to specimen part
Whether residue stress meets the off-line test of preset index, if qualified, performs S4, if index is unqualified, performs S1；
S4：Nargin analysis of resonating is carried out to the part after the reinforcing based on Campbell figures, and it is abundant according to the resonance
Degree analysis carries out intrinsic frequency adjustment to the part after the reinforcing so that the operation interval satisfaction of the part after the reinforcing sets
Meter requirement, obtains the part after frequency modulation；
S5：Judge whether the part laser peening frequency modulation mass index after the frequency modulation is qualified, if resonance nargin is not less than
10% and endurance percentage be not less than 30%, then perform S6, if resonance nargin less than 10% or endurance percentage it is little
In 30%, then S4 is performed；
S6：The selection of part school shape region is carried out to the part after the frequency modulation, one is applied to the part school shape region
Reverse impact load, to carry out Deformation Repair to the part after the frequency modulation；
S7：Judge whether the part school form quality amount after the shape of school is qualified, if the accessory size after the school shape is qualified, part
Process terminates, if unqualified, performs S6.
Preferably, it is described that laser peening strengthening region of the parameter to the pending part is strengthened according to preset laser peening
Laser peening intensive treatment is carried out, the part after being strengthened is specifically included：
The top layer of the pending part is coated with absorbed layer, and to the top layer of the pending part water constraint layer is applied,
Laser peening reinforcing is carried out to the laser peening strengthening region of the pending part further according to preset laser peening reinforcing parameter
Process, the part after being strengthened.
Preferably, it is described that nargin analysis of resonating is carried out to the part after the reinforcing based on Campbell figures, and according to institute
State resonance nargin analysis carries out intrinsic frequency adjustment to the part after the reinforcing so that the workspace of the part after the reinforcing
Between meet design requirement, obtain also including before the part after frequency modulation：
Model analysis is carried out to the part after the reinforcing, the part after the reinforcing is obtained intrinsic under different rotating speeds
Frequency and the vibration shape.
Preferably, it is described that nargin analysis of resonating is carried out to the part after the reinforcing based on Campbell figures, and according to institute
State resonance nargin analysis carries out intrinsic frequency adjustment to the part after the reinforcing so that the workspace of the part after the reinforcing
Between meet design requirement, obtain the part after frequency modulation and specifically include：
As abscissa, frequency is ordinate to rotating speed with the part after the reinforcing, is drawn and the part after the reinforcing
Corresponding Campbell figures, nargin analysis of resonating is carried out based on the Campbell figures to the part after the reinforcing；
The top layer of the part after the reinforcing is coated with absorbed layer, and to the top layer of the part after the reinforcing water constraint is applied
Layer, by arranging part zone area and laser peening impact depth, after being analyzed to the reinforcing according to the resonance nargin
Part carries out intrinsic frequency adjustment so that the operation interval of the part after the reinforcing meets design requirement, after obtaining frequency modulation
Part.
Preferably, the part to after the frequency modulation carries out the selection of part school shape region, to the part school shape region
Apply a reverse impact load, specifically included with carrying out Deformation Repair to the part after the frequency modulation：
School shape mechanical model is set up with the part after frequency modulation, by numerical simulation, according to the school shape mechanical model to institute
Stating the part after frequency modulation carries out the selection of part school shape region, then applies a reverse impact load to the part school shape region,
To carry out Deformation Repair to the part after the frequency modulation.
Preferably, the resonance nargin is obtained by a computing formula, and the computing formula is：
Wherein, wherein fdFor part in rotating speed n actual dynamic frequency, unit is Hz；It is r/min that n is design speed unit；
KnFor rotating speed multiplying power.
Preferably, the embodiment of the present invention additionally provides a kind of polynary control device of reverse laser peening, it is characterised in that bag
Include：Five degree of freedom workbench, motion controller, laser instrument, laser controller, optical measurement camera, graphics process work station and
Main frame；
Described motion controller one end and the five degree of freedom workbench connect, the motion controller other end and described
Main frame connects；
Described laser controller one end and the laser instrument connect, and the laser controller other end and the main frame connect
Connect；
Described graphics process work station one end and the optical measurement camera connect, the graphics process work station other end
With main frame connection.
Wherein, main frame, treating parts processed for basis carries out the laser spray that structural analysis and residual stress test are obtained
Ball strengthens index and technological parameter, determines the laser peening strengthening region of the pending part；
Main frame, is additionally operable to strengthen parameter according to preset laser peening, using laser of the laser instrument to the pending part
Shot peening strengthening region carries out laser peening intensive treatment, the part after being strengthened；
Main frame, is additionally operable to be sampled the part after the reinforcing and obtains specimen part, then specimen part is carried out tired
Whether labor life-span, residual stress meet the off-line test of preset index, if qualified, based on Campbell figures to described strong
Part after change carries out nargin analysis of resonating, and according to the resonance nargin analysis and utilization laser instrument to the part after the reinforcing
Carry out intrinsic frequency adjustment so that the operation interval of the part after the reinforcing meets design requirement, obtain the part after frequency modulation；
Main frame, is additionally operable to judge whether the part laser peening frequency modulation mass index after the frequency modulation is qualified, if resonance is abundant
Degree is not less than 10% and endurance percentage is not less than 30%, then the choosing of part school shape region is carried out to the part after the frequency modulation
Take, one reverse impact load is applied to the part school shape region using laser instrument, to carry out to the part after the frequency modulation
Deformation Repair；
Main frame, is additionally operable to judge that the part school form quality amount after the shape of school is by optical measurement camera and graphics process work station
No qualified, if the accessory size after the school shape is qualified, part process terminates.
Preferably, a kind of polynary control device of reverse laser peening provided in an embodiment of the present invention also includes：Painting water spray pipe,
Modal analysis system, acceleration transducer；
The painting water spray pipe and the connection of described laser controller one end, the laser controller other end connects with the main frame
Connect；
Described modal analysis system one end and acceleration transducer connection, the modal analysis system other end and institute
State main frame connection.
Preferably, the five degree of freedom workbench includes：Fixture integrated and counter weight base.
Preferably, the modal analysis system includes：Modification amplifier, elastic excitation hammer, signal analyzer and analysis are soft
Part.
As can be seen from the above technical solutions, the embodiment of the present invention has advantages below：
A kind of polynary control method of reverse laser peening and device are embodiments provided, wherein, the reverse laser
The polynary control method of shot-peening includes：S1：The laser that structural analysis and residual stress test are obtained is carried out according to parts processed is treated
Shot peening strengthening index and technological parameter, determine the laser peening strengthening region of the pending part；S2：Sprayed according to preset laser
Ball reinforcing parameter carries out laser peening intensive treatment to the laser peening strengthening region of the pending part, after being strengthened
Part；S3：Part after the reinforcing is sampled and obtains specimen part, then fatigue life, remnants are carried out to specimen part
Whether stress meets the off-line test of preset index, if qualified, performs S4, if index is unqualified, performs S1；S4：
Nargin analysis of resonating is carried out to the part after the reinforcing based on Campbell figures, and is analyzed to described according to the resonance nargin
Part after reinforcing carries out intrinsic frequency adjustment so that the operation interval of the part after the reinforcing meets design requirement, obtains
Part after frequency modulation；S5：Judge whether the part laser peening frequency modulation mass index after the frequency modulation is qualified, if resonance nargin is not
Less than 10% and endurance percentage is not less than 30%, then S6 is performed, if resonance nargin is less than 10% or endurance percentage
Than less than 30%, then performing S4；S6：The selection of part school shape region is carried out to the part after the frequency modulation, to part school shape
Region applies a reverse impact load, to carry out Deformation Repair to the part after the frequency modulation；S7：Judge the part after the shape of school
Whether school form quality amount is qualified, if the accessory size after the school shape is qualified, part process terminates, if unqualified, performs S6.
The skin-material reinforcing of rotating part is carried out using the knock wave mechanics effect of induced with laser, belongs to noncontact processing, reinforcing effect
Fruit is significantly.The skin-material modification characteristic that the present invention is produced using laser peening, appropriate design laser peening processing region area
And impact depth, lamination alternation of cross-section part Young's modulus is built, so as to change intrinsic frequency, realize reinforcing with frequency modulation process
Dual purpose, and the malformation problem of generally existing is processed for laser peening, using mechanical model modeling analysis, preferred school
Shape region and parameter, by Opposite side loading shock loading the reparation of part deformation is realized, is solved laser peening accessory size and is stablized
Property a difficult problem, it is possible to meet rotation class part every demand, be especially suitable for bearing the high speed rotating part of aerodynamic loading, such as
Gas turbine blades, blade of aviation engine etc..
Description of the drawings
In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing
The accompanying drawing to be used needed for having technology description is briefly described, it should be apparent that, drawings in the following description are only this
Some embodiments of invention, for those of ordinary skill in the art, without having to pay creative labor, may be used also
To obtain other accompanying drawings according to these accompanying drawings.
Fig. 1 is a kind of schematic flow sheet of the polynary control method of reverse laser peening provided in an embodiment of the present invention；
Fig. 2 is a kind of another schematic flow sheet of the polynary control method of reverse laser peening provided in an embodiment of the present invention；
Fig. 3 is a kind of structural representation of the polynary control device of reverse laser peening provided in an embodiment of the present invention；
Fig. 4 is blade of aviation engine strengthening region schematic diagram；
Fig. 5 is blade of aviation engine vibration analysis Campbell figures；
Fig. 6 is blade of aviation engine frequency modulation area schematic；
Fig. 7 is that blade of aviation engine reversely controls shape schematic diagram.
Wherein, mark in figure as described below：
1. 2. five degree of freedom workbench of pending part, 3. motion controller 4. applies the laser of 5. laser instrument of water spray pipe 6.
The main frame of 10. graphics process work station of controller 7. acceleration transducer, 8. modal analysis system, 9. optical measurement camera 11.
The exhaust 1-2 ranks of 15. blade root of side, 16. blade face frequency modulation region, 17. blade center area 18. of 12. blade, 13. leading edge 14. are shaken
The laser peening school shape loading direction of 19. deformable blade direction of type maximum displacement border 20.
Specific embodiment
A kind of polynary control method of reverse laser peening and device are embodiments provided, existing high speed rotation is overcome
Turn reinforcing, frequency modulation and the nonsynchronous problem of school shape technique of part, and realized using laser peening reinforcing, frequency modulation and school shape ability
The polynary process of part, lift structure fatigue life, the resonance nargin ensured in part time job rotating speed.
To enable goal of the invention, feature, the advantage of the present invention more obvious and understandable, below in conjunction with the present invention
Accompanying drawing in embodiment, is clearly and completely described, it is clear that disclosed below to the technical scheme in the embodiment of the present invention
Embodiment be only a part of embodiment of the invention, and not all embodiment.Based on the embodiment in the present invention, this area
All other embodiment that those of ordinary skill is obtained under the premise of creative work is not made, belongs to protection of the present invention
Scope.
Refer to Fig. 1, a kind of one embodiment of the polynary control method of reverse laser peening provided in an embodiment of the present invention,
Including：
101st, basis treats parts processed and carries out the laser peening reinforcing index that structural analysis and residual stress test are obtained
And technological parameter, determine the laser peening strengthening region of pending part；
Main frame carries out the laser peening reinforcing index that structural analysis and residual stress test are obtained according to parts processed is treated
And technological parameter, determine the laser peening strengthening region of pending part.
102nd, the laser peening strengthening region for treating parts processed according to preset laser peening reinforcing parameter carries out laser spray
Ball intensive treatment, the part after being strengthened；
Main frame carries out laser spray according to the laser peening strengthening region that preset laser peening reinforcing parameter treats parts processed
Ball intensive treatment, the part after being strengthened.
103rd, the part after reinforcing is sampled and obtains specimen part, then fatigue life, remnants are carried out to specimen part
Whether stress meets the off-line test of preset index, if qualified, performs 104, if index is unqualified, performs 101；
It is strong that the laser peening strengthening region for treating parts processed according to preset laser peening reinforcing parameter carries out laser peening
Change is processed, and after the part after being strengthened, main frame is sampled to the part after reinforcing and obtains specimen part, then to specimen part
Carry out whether fatigue life, residual stress meet the off-line test of preset index, if qualified, perform 104, if index is not
It is qualified, then perform 101.
104th, nargin analysis of resonating is carried out to the part after reinforcing based on Campbell figures, and it is right according to resonance nargin analysis
Part after reinforcing carries out intrinsic frequency adjustment so that the operation interval of the part after reinforcing meets design requirement, obtains frequency modulation
Part afterwards；
After judging the part qualified after reinforcing, it is abundant that main frame carries out resonance to the part after reinforcing based on Campbell figures
Degree analysis, and intrinsic frequency adjustment is carried out to the part after reinforcing according to resonance nargin analysis so that the work of the part after reinforcing
Meet design requirement as interval, obtain the part after frequency modulation.
105th, judge whether to resonate nargin not less than 10% and endurance percentage is not less than 30%, if so, then perform
106, if it is not, then performing 104；
Main frame judges whether the part laser peening frequency modulation mass index after frequency modulation is qualified, if resonance nargin is not less than 10%
And endurance percentage is not less than 30%, then perform 106, if resonance nargin is less than 10% or endurance percentage is less than
30%, then perform 104.
106th, the selection of part school shape region is carried out to the part after frequency modulation, a reverse impact is applied to part school shape region
Load, to carry out Deformation Repair to the part after frequency modulation；
Main frame carries out the selection of part school shape region to the part after frequency modulation, and to part school shape region a reverse impact is applied
Load, to carry out Deformation Repair to the part after frequency modulation.
107th, judge whether the accessory size after the shape of school is qualified, and if so, then part process terminates, if it is not, then performing
106。
Main frame judges whether the part school form quality amount after the shape of school is qualified, if the accessory size after the shape of school is qualified, at part
Reason terminates, if unqualified, performs 106.
Refer to Fig. 2, a kind of another enforcement of the polynary control method of reverse laser peening provided in an embodiment of the present invention
Example, including：
201st, basis treats parts processed and carries out the laser peening reinforcing index that structural analysis and residual stress test are obtained
And technological parameter, determine the laser peening strengthening region of pending part；
Main frame carries out the laser peening reinforcing index that structural analysis and residual stress test are obtained according to parts processed is treated
And technological parameter, determine the laser peening strengthening region of pending part.
202nd, the top layer of pending part is coated with absorbed layer, and the top layer for treating parts processed applies water constraint layer, then root
The laser peening strengthening region for treating parts processed according to preset laser peening reinforcing parameter carries out laser peening intensive treatment, obtains
Part after reinforcing；
The top layer of pending part is coated with absorbed layer, and host computer applies the top layer applying water that water dispenser device treats parts processed
Restraint layer, it is strong that the laser peening strengthening region for treating parts processed further according to preset laser peening reinforcing parameter carries out laser peening
Change is processed, the part after being strengthened.
203rd, the part after reinforcing is sampled and obtains specimen part, then fatigue life, remnants are carried out to specimen part
Whether stress meets the off-line test of preset index, if qualified, performs 204, if index is unqualified, performs 201；
It is strong that the laser peening strengthening region for treating parts processed according to preset laser peening reinforcing parameter carries out laser peening
Change is processed, and after the part after being strengthened, main frame is sampled to the part after reinforcing and obtains specimen part, then to specimen part
Carry out whether fatigue life, residual stress meet the off-line test of preset index, if qualified, perform 204, if index is not
It is qualified, then perform 201.
204th, model analysis is carried out to the part after reinforcing, intrinsic frequency of the part after being strengthened under different rotating speeds
And the vibration shape；
Main frame carries out model analysis to the part after reinforcing, intrinsic frequency of the part after being strengthened under different rotating speeds
And the vibration shape.
205th, as abscissa, frequency is ordinate to the rotating speed with the part after reinforcing, draws corresponding with the part after reinforcing
Campbell figure, based on Campbell figures to the part after reinforcing carry out resonate nargin analysis；
After judging the part qualified after reinforcing, as abscissa, frequency is vertical to the rotating speed of part of the main frame after strengthening
Coordinate, draws Campbell figures corresponding with the part after reinforcing, and the part after reinforcing is resonated based on Campbell figures
Nargin is analyzed.
The top layer of the part after the 206th, strengthening is coated with absorbed layer, and to the top layer of the part after reinforcing water constraint layer is applied,
By arranging part zone area and laser peening impact depth, the part after reinforcing is carried out inherently according to resonance nargin analysis
Frequency is adjusted so that the operation interval of the part after reinforcing meets design requirement, obtains the part after frequency modulation；
The top layer of the part after reinforcing is coated with absorbed layer, and host computer applies water dispenser device and the top layer of the part after reinforcing is applied
Plus water constraint layer, by arranging part zone area and laser peening impact depth, after being analyzed to reinforcing according to resonance nargin
Part carries out intrinsic frequency adjustment so that the operation interval of the part after reinforcing meets design requirement, obtains the part after frequency modulation.
207th, judge whether to resonate nargin not less than 10% and endurance percentage is not less than 30%, if so, then perform
208, if it is not, then performing 205；
Main frame judges whether the part laser peening frequency modulation mass index after frequency modulation is qualified, if resonance nargin is not less than 10%
And endurance percentage is not less than 30%, then perform 208, if resonance nargin is less than 10% or endurance percentage is less than
30%, then perform 205.
208th, school shape mechanical model is set up with the part after frequency modulation, by numerical simulation, is exchanged according to school shape mechanical model
Part after frequency carries out the selection of part school shape region, then applies a reverse impact load to part school shape region, with to frequency modulation
Part afterwards carries out Deformation Repair；
Main frame sets up school shape mechanical model with the part after frequency modulation, by numerical simulation, is exchanged according to school shape mechanical model
Part after frequency carries out the selection of part school shape region, then applies a reverse impact load to part school shape region, with to frequency modulation
Part afterwards carries out Deformation Repair.
209th, judge whether the accessory size after the shape of school is qualified, and if so, then part process terminates, if it is not, then performing
208。
Main frame judges whether the part school form quality amount after the shape of school is qualified, if the accessory size after the shape of school is qualified, at part
Reason terminates, if unqualified, performs 208.
In the present embodiment, the detailed process of the polynary control method of reverse laser peening is：
First, the plasma shock wave for being produced using intense laser beam forms intensive, stable dislocation structure in material surface
With residual compressive stress, material surface is set to produce strain hardening.Residual compressive stress can reduce the tensile stress level in alternate load, make
Mean stress level declines, so as to improve fatigue crack initiation life.Simultaneously the presence of residual compressive stress, can cause closing for crackle
Effect is closed, so as to effectively reduce the driving force of crack Propagation, extends Crack Growth Fatigue Life.
Then, resonate nargin analysis and the analysis of dynamic stress nargin are carried out to part, is formed using laser peening impact part
Variation rigidity region, by arranging zones of different area and impact depth, accuracy controlling part intrinsic frequency, is allowed to avoid certain frequency
Rate scope, in trouble free service frequency field.
Finally, the accessory size deviation for causing with frequency modulation for laser peening reinforcing, by mechanical modeling analysis and numerical value
Emulation technology, preferred school shape processing region realizes the reparation of part deformation by applying reverse impact load.
Refer to Fig. 3, a kind of one embodiment of the polynary control device of reverse laser peening provided in an embodiment of the present invention,
Including：
At five degree of freedom workbench 2, motion controller 3, laser instrument 5, laser controller 6, optical measurement camera 9, figure
Reason work station 10 and main frame 11；
The one end of motion controller 3 and five degree of freedom workbench 2 connect, and the other end of motion controller 3 and main frame 11 connect；
The one end of laser controller 6 and laser instrument 5 connect, and the other end of laser controller 6 and main frame 11 connect；
The one end of graphics process work station 10 and optical measurement camera 9 connect, the other end of graphics process work station 10 and main frame
11 connections.
In the present embodiment, optical measurement camera has whole audience scan function, coordinates graphics process work station, can carry out
The three-dimensionalreconstruction of accessory size is tested with real-time deformation, it is ensured that part school shape stage size precision.
Main frame is connected with motion controller, laser controller, graphics process work station and modal analysis system, keeps real
When data exchange, the reinforcing, frequency modulation and school shape stage in part, system host is right by theory analysis and numerical simulation technology
Technological parameter real-time optimization and iteration, it is ensured that the precise high-efficiency of whole technology chain.
A kind of polynary control device of reverse laser peening provided in an embodiment of the present invention also includes：Apply water spray pipe 4, acceleration
Sensor 7, modal analysis system 8；
Water spray pipe 4 and the connection of the one end of laser controller 6 are applied, the other end of laser controller 6 is connected with main frame 11；
The one end of modal analysis system 8 and acceleration transducer 7 connect, and the other end of modal analysis system 8 and main frame 11 connect.
Five degree of freedom workbench 2 includes：Fixture integrated and counter weight base, fixture integrated and counter weight base can keep
It is sufficiently stiff, it is exclusively used in part intrinsic frequency detection demand.
Modal analysis system 8 includes：Modification amplifier, elastic excitation hammer, signal analyzer and analysis software, system can
Ensure the accurate of test data and stablize.
The above is the detailed description to a kind of polynary control method of reverse laser peening and device, for ease of understanding, below
Application with a concrete application scene to a kind of polynary control method of reverse laser peening and device is illustrated, application examples bag
Include：
Using blade of aviation engine as research object, as shown in Fig. 3 to Fig. 7, blade of aviation engine laser peening is strong
Change, the implementation steps of frequency modulation and school shape are：
(1) part status assessment：Blade of aviation engine structure is analyzed using finite element software MSC.Nastran, is adopted
Residual stress at XRD methods detection blade leading edge, exhaust side and blade root, determines laser peening reinforcing index and technological parameter.
Pending part 1 (i.e. blade) is fixed on five degree of freedom workbench 2.
(2) strengthening region is arranged：As shown in figure 4, according to structural analysis and residual stress test result, determining leading edge
13rd, side 14 and the position laser peening strengthening region size of blade root 15 are vented, improve region of stress concentration residual stress amplitude, lifted
Important load region fatigue crack initiation life.
(3) laser peening reinforcing：As shown in figure 4, blade top layer applies absorbed layer, Tu Shui robots (applying water spray pipe 4) are applied
Plus water constraint layer, implement laser peening reinforcing according to parameter preset.
(4) reinforcing quality is judged：The problem with high costs for blade of aviation engine, chooses same material and makes profile
Simple sample, with same process parameter laser peening reinforcing is carried out, to sample fatigue life, residual stress index off-line test,
Such as qualified, then terminate laser peening intensive treatment；Such as index is unqualified, then repeat step (2)-(4), until part is strong
Change qualified.
(5) model analysis：Using the natural mode of vibration (1-15 ranks) of finite element analysis blade of aviation engine, obtain blade and exist
Eigenfrequncies and vibration models under various rotating speed, should include the typical rotating speed on flight profile, mission profile in operating mode：Idling, take off, cruise and
Landing working speed.
(6) resonance analyzing：As shown in figure 5, drawing the Campbell figures of blade of aviation engine, abscissa turns for part
Speed, ordinate is frequency.Free running frequency represents by horizontal line is fixed, the intrinsic frequency under correspondence blade different modalities；Force
Oscillating component, i.e., relevant with rotating speed frequency content is presented on the ray drawn with origin, the various internal excitings of ray representation
Power.Such as intrinsic frequency straight line and ray intersection, then it may happen that resonance.Nargin analysis of resonating is carried out based on Campbell figures,
Consider blade key rotating speed and the resonance nargin that need to be met.
(7) nargin that resonates assessment：In the range of all design speeds of blade, resonance nargin meets claimed below：
Wherein, wherein fdFor part in rotating speed n actual dynamic frequency, unit is Hz；It is r/min that n is design speed unit；
KnFor rotating speed multiplying power.
(8) laser peening frequency modulation：Blade top layer applies absorbed layer, and Tu Shui robots apply water constraint layer, as shown in fig. 6,
With 1-2 first order mode maximum displacements border 18 as boundary, zones of different area and laser peening impact are set in blade center area 17
Depth, based on nargin analysis of resonating, in blade frequency modulation region 16 part intrinsic frequency is adjusted, it is ensured that blade working is interval full
Foot resonance margin requirement.
(9) frequency modulation mass is judged：The addition counterweight of five degree of freedom workbench 2 ensures rigidity, carries out blade modal testing experiment,
Acceleration transducer 7 is fixed into three sections of blade upper, middle and lower, is tapped as driving source, pilot blade laser peening using elastic excitation hammer
Intrinsic frequency after frequency modulation process.Index is resonance nargin >=10%, endurance percentage >=30%.As frequency modulation index reaches
Mark, then terminate the process of laser peening frequency modulation；Such as index is unqualified, then repeat step (7)-(9), until part frequency modulation is up to standard.
(10) school shape mechanical model：Blade is completed after laser peening reinforcing and frequency modulation, by optical measurement camera 9 and figure
Processing workstation 10 measures deformable blade 3D data, and with deformed vanes geometric shape laser peening school shape mechanical model is set up.
(11) shape region in school is preferred：Main frame 11 is excellent based on the shape mechanical model of school by theory analysis and numerical simulation
Select part school shape region.
(12) reverse laser peening control shape：As shown in fig. 7, the reverse side in deformable blade direction 19 applies a reverse impact
Load (as shown in laser peening loading direction 20 in figure), realizes the reparation of deformable blade amount, the applying zone of shock loading and
Load parameter is obtained by mechanical model and numerical value iteration of simulations.
(13) school shape quality testing：Optical measurement camera 9 and the on-line checking blade school form quality amount of graphics process work station 10,
Such as size qualification, then step (14) is gone to；Such as accessory size is unqualified, then repeat step (11)-(13), until blade dimensions are closed
Lattice.
(14) the polynary control flow of reverse control shape laser peening of the change intrinsic frequency of blade of aviation engine terminates.
The above, above example only to illustrate technical scheme, rather than a limitation；Although with reference to front
State embodiment to be described in detail the present invention, it will be understood by those within the art that：It still can be to front
State the technical scheme described in each embodiment to modify, or equivalent is carried out to which part technical characteristic；And these
Modification is replaced, and does not make the spirit and scope of the essence disengaging various embodiments of the present invention technical scheme of appropriate technical solution.
Claims (10)
1. the polynary control method of a kind of reverse laser peening, it is characterised in that include：
S1：Laser peening reinforcing index and the technique that structural analysis and residual stress test are obtained is carried out according to parts processed is treated
Parameter, determines the laser peening strengthening region of the pending part；
S2：Strengthen parameter according to preset laser peening carries out laser peening to the laser peening strengthening region of the pending part
Intensive treatment, the part after being strengthened；
S3：Part after the reinforcing is sampled and obtains specimen part, then specimen part is carried out fatigue life, it is remaining should
Whether power meets the off-line test of preset index, if qualified, performs S4, if index is unqualified, performs S1；
S4：Nargin analysis of resonating is carried out to the part after the reinforcing based on Campbell figures, and according to the resonance nargin point
Analysis carries out intrinsic frequency adjustment to the part after the reinforcing so that the operation interval of the part after the reinforcing meets design will
Ask, obtain the part after frequency modulation；
S5：Judge whether the part laser peening frequency modulation mass index after the frequency modulation is qualified, if resonance nargin is not less than 10%
And endurance percentage is not less than 30%, then perform S6, if resonance nargin is less than 10% or endurance percentage is less than
30%, then perform S4；
S6：The selection of part school shape region is carried out to the part after the frequency modulation, one is applied to the part school shape region reversely
Shock loading, to carry out Deformation Repair to the part after the frequency modulation；
S7：Judge whether the part school form quality amount after the shape of school is qualified, if the accessory size after the school shape is qualified, part process
Terminate, if unqualified, perform S6.
2. the polynary control method of reverse laser peening according to claim 1, it is characterised in that described according to preset laser
Shot peening strengthening parameter carries out laser peening intensive treatment to the laser peening strengthening region of the pending part, after being strengthened
Part specifically include：
The top layer of the pending part is coated with absorbed layer, and to the top layer of the pending part water constraint layer, then root are applied
Laser peening intensive treatment is carried out to the laser peening strengthening region of the pending part according to preset laser peening reinforcing parameter,
Part after being strengthened.
3. the polynary control method of reverse laser peening according to claim 1, it is characterised in that described based on Campbell
Figure carries out nargin analysis of resonating to the part after the reinforcing, and is analyzed to the part after the reinforcing according to the resonance nargin
Carry out intrinsic frequency adjustment so that the operation interval of the part after the reinforcing meets design requirement, obtain the part after frequency modulation
Also include before：
Model analysis is carried out to the part after the reinforcing, intrinsic frequency of the part after the reinforcing under different rotating speeds is obtained
And the vibration shape.
4. the polynary control method of reverse laser peening according to claim 3, it is characterised in that described based on Campbell
Figure carries out nargin analysis of resonating to the part after the reinforcing, and is analyzed to the part after the reinforcing according to the resonance nargin
Carry out intrinsic frequency adjustment so that the operation interval of the part after the reinforcing meets design requirement, obtain the part after frequency modulation
Specifically include：
As abscissa, frequency is ordinate to rotating speed with the part after the reinforcing, is drawn corresponding with the part after the reinforcing
Campbell figure, based on the Campbell figures to the part after the reinforcing carry out resonate nargin analysis；
The top layer of the part after the reinforcing is coated with absorbed layer, and to the top layer of the part after the reinforcing water constraint layer is applied,
By arranging part zone area and laser peening impact depth, analyzed to the part after the reinforcing according to the resonance nargin
Carry out intrinsic frequency adjustment so that the operation interval of the part after the reinforcing meets design requirement, obtain the part after frequency modulation.
5. according to the polynary control method of reverse laser peening described in claim 1, it is characterised in that it is described to the frequency modulation after
Part carries out the selection of part school shape region, applies a reverse impact load to the part school shape region, with to the frequency modulation
Part afterwards carries out Deformation Repair and specifically includes：
School shape mechanical model is set up with the part after frequency modulation, by numerical simulation, according to the school shape mechanical model to the tune
Part after frequency carries out the selection of part school shape region, then applies a reverse impact load to the part school shape region, with right
Part after the frequency modulation carries out Deformation Repair.
6. according to the polynary control method of reverse laser peening described in claim 1, it is characterised in that the resonance nargin passes through one
Computing formula is obtained, and the computing formula is：
Wherein, wherein fdFor part in rotating speed n actual dynamic frequency, unit is Hz；It is r/min that n is design speed unit；KnFor
Rotating speed multiplying power.
7. the polynary control device of a kind of reverse laser peening, it is characterised in that include：Five degree of freedom workbench, motion controller,
Laser instrument, laser controller, optical measurement camera, graphics process work station and main frame；
Described motion controller one end and five degree of freedom workbench connection, the motion controller other end and the main frame
Connection；
Described laser controller one end and the laser instrument connect, and the laser controller other end and the main frame connect；
Described graphics process work station one end and optical measurement camera connection, the graphics process work station other end and institute
State main frame connection；
Wherein, main frame, for carry out the laser peening that structural analysis and residual stress test obtain strong according to parts processed is treated
Change index and technological parameter, determine the laser peening strengthening region of the pending part；
Main frame, is additionally operable to strengthen parameter according to preset laser peening, using laser peening of the laser instrument to the pending part
Strengthening region carries out laser peening intensive treatment, the part after being strengthened；
Main frame, is additionally operable to be sampled the part after the reinforcing and obtains specimen part, then carries out the tired longevity to specimen part
Whether life, residual stress meet the off-line test of preset index, if qualified, based on Campbell figures to the reinforcing after
Part carry out resonate nargin analysis, and according to it is described resonance nargin analysis and utilization laser instrument the part after the reinforcing is carried out
Intrinsic frequency is adjusted so that the operation interval of the part after the reinforcing meets design requirement, obtains the part after frequency modulation；
Main frame, is additionally operable to judge whether the part laser peening frequency modulation mass index after the frequency modulation is qualified, if resonance nargin is not
Less than 10% and endurance percentage be not less than 30%, then the part after the frequency modulation is carried out part school shape region selection,
One reverse impact load is applied to the part school shape region using laser instrument, to deform to the part after the frequency modulation
Repair；
Main frame, is additionally operable to judge whether the part school form quality amount after the shape of school closes by optical measurement camera and graphics process work station
Lattice, if the accessory size after the school shape is qualified, part process terminates.
8. the polynary control device of reverse laser peening according to claim 7, it is characterised in that also include：Painting water spray pipe,
Modal analysis system, acceleration transducer；
The painting water spray pipe and the connection of described laser controller one end, the laser controller other end is connected with the main frame；
Described modal analysis system one end and acceleration transducer connection, the modal analysis system other end and the master
Machine connects.
9. the polynary control device of reverse laser peening according to claim 7, it is characterised in that the five degree of freedom work
Platform includes：Fixture integrated and counter weight base.
10. the polynary control device of reverse laser peening according to claim 7, it is characterised in that the model analysis system
System includes：Modification amplifier, elastic excitation hammer, signal analyzer and analysis software.
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| CN109583037A (en) * | 2018-11-06 | 2019-04-05 | 西北工业大学 | A kind of parameter control method of blade of aviation engine shot-peening machining deformation |
| CN110586695A (en) * | 2019-07-31 | 2019-12-20 | 广东工业大学 | Laser shock peening and shape correction method and device for engine bifurcated tail nozzle welding seam |
| CN110900463A (en) * | 2018-09-17 | 2020-03-24 | 鲍臻 | Automatic shot blasting forming device and method for synchronous cambered surface forming hammer |
| CN111055086A (en) * | 2019-12-27 | 2020-04-24 | 北京航空航天大学 | Surface modification and residual stress regulation and control method for trace removal after shot peening |
| CN112048614A (en) * | 2020-09-10 | 2020-12-08 | 中国航发沈阳黎明航空发动机有限责任公司 | Hollow blade life-prolonging shape-controlling method based on laser shock peening |
| CN113312825A (en) * | 2021-06-18 | 2021-08-27 | 广东工业大学 | Laser shot peening effect monitoring method and device |
| CN114592119A (en) * | 2022-03-14 | 2022-06-07 | 中国航空制造技术研究院 | Laser shock peening method based on prestress |
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| CN113312825B (en) * | 2021-06-18 | 2022-03-22 | 广东工业大学 | Laser shot peening effect monitoring method and device |
| CN114592119A (en) * | 2022-03-14 | 2022-06-07 | 中国航空制造技术研究院 | Laser shock peening method based on prestress |
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