CN106769853A - The Forecasting Methodology of CFRP and titanium alloy laminated construction drilling lamination defect - Google Patents

Abstract

The present invention provides the Forecasting Methodology of a kind of CFRP and titanium alloy laminated construction drilling lamination defect, is related to carbon fibre composite and titanium alloy lamination mounting technology field.The method produces the axis critical force of lamination defect by analytical Calculation carbon fibre composite, set up the mapping relations model of carbon fibre composite and titanium alloy laminated construction lamination defect evaluation analysis model, steady drilling starting stage axial cutting force computation model and axial cutting force with drilling number change, according to conditions such as current drill structure parameter, drill process parameter and drilling quantity, can boring procedure be judged produce lamination defect, and forecast analysis lamination defect region maximum gauge.The present invention can predict the maximum drilling hole amount for meeting setting lamination defect standard, effectively improve the qualification rate of drilling cutting-tool's used life and laminated construction drilling, prevent because more than part rejection caused by lamination defect standard, saving production cost.

Description

The Forecasting Methodology of CFRP and titanium alloy laminated construction drilling lamination defect

Technical field

The present invention relates to carbon fibre composite and titanium alloy lamination mounting technology field, more particularly to a kind of CFRP and titanium The Forecasting Methodology of alloy stack structure drilling lamination defect.

Background technology

Carbon fibre composite (CFRP) has the series of advantages such as density is low, intensity is high, specific strength is big, absorbing is good, It is widely used in fields such as Aero-Space, automobile, guided missiles.For example, the passenger plane fuselage surface 90% of Boeing 787 is all employed Carbon fibre composite, the new aviation aircraft of China also gradually increases the ratio that carbon fibre composite is used, aviation flight The application percentage of device composite and titanium alloy has become weighs one of its advanced important indicator.

As advanced aviation aircraft widely uses carbon fibre composite, carbon fibre composite is filled with titanium alloy lamination The drilling demand of distribution structure is increasing, and the assembling of the passenger plane of Boeing 787 needs 4,000,000 carbon fibre composites of drilling and titanium alloy Laminated construction hole.Due to the difficult processing characteristics and its mutually restriction, influence of carbon fibre composite and titanium alloy, drilling process is deposited Drilling efficiency is low, drilling quality be difficult to ensure, the unmanageable outstanding problem of part rejection rate.It is reported that flying both at home and abroad During machine assembling, the carbon fibre composite number of parts scrapped is caused to account for whole because of the lamination defect that drilling processing is produced More than the 60% of faulty part.Because even being that very small layering is also very serious potential safety hazard, and carbon fiber is multiple Condensation material finished surface cannot almost be repaired and retrieved once there is the major defect such as tear and layering.

Due to lacking effective laminated construction drilling lamination defect Forecasting Methodology, operating personnel are difficult to judge in Present Borehole Under the conditions of, standard causes part rejection beyond related mark when to produce lamination defect or delamination area diameter, can only basis Experience reduces drilling quantity, therefore greatly reduces drilling cutting-tool's used life, and artificial improves drilling cost.

For carbon fibre composite drilling lamination defect, substantial amounts of research work has been carried out both at home and abroad, successively proposed " the critical axial cutting force " that produces lamination defect is theoretical, lamination defect diameter evaluation points and lamination defect area evaluate because Son, for the forecast analysis of lamination defect provides theoretical foundation, and proposes the Forecasting Methodology of correlation respectively.

The Forecasting Methodology of current carbon fibre composite drilling lamination defect has the following disadvantages：(1) existing Forecasting Methodology The independent borehole conditions of carbon fibre composite are only applicable to, are drilled with titanium alloy laminated construction without proposition carbon fibre composite Under the conditions of effective lamination defect Forecasting Methodology.Titanium alloy material is to bore cutter in due to not accounting for laminated construction boring procedure Have the influence of abrasion, thus these Forecasting Methodologies are not suitable for laminated construction；(2) existing Forecasting Methodology is based on lamination defect area Domain diameter is proposed with the relational model of boring procedure static state cutting force, it is impossible to enough analyze what index drilling hole amount reaches Afterwards, delamination area diameter exceedes the defect standard specified, thus is unsatisfactory for lamination defect dynamic realtime prediction point in boring procedure The engineering actual demand of analysis.

The content of the invention

For the defect of prior art, it is pre- with titanium alloy laminated construction drilling lamination defect that the present invention provides a kind of CFRP Survey method, according to conditions such as current drill structure parameter, drill process parameter and drilling quantity, judges that can boring procedure produce Lamination defect, and forecast analysis lamination defect region maximum gauge, can predict meet setting lamination defect standard maximum Drilling hole amount, effectively improves drilling qualification rate, reduces because beyond part rejection rate caused by lamination defect standard.

A kind of CFRP and the Forecasting Methodology of titanium alloy laminated construction drilling lamination defect, comprise the following steps that：

Step 1, setting lamination defect requirement, i.e., lamination defect region maximum gauge allowable；

Step 2, the critical axial cutting force for calculating carbon fibre composite generation lamination defect；

Step 2.1, based on economics analysis method, set up the critical axial direction that carbon fibre composite drilling produces lamination defect Cutting force computing formula, as shown in formula (1)；

Wherein, F_AIt is borehole axial cutting force, G_ICIt is the extension energy of carbon fibre composite crackle in unit area, E It is the modulus of elasticity in static bending, h is carbon fibre composite thickness in monolayer, and v is Poisson's ratio；

Step 2.2, using super depth-of-field microscope observation, measurement composite board, obtain carbon fibre composite sheet material Thickness in monolayer；

Step 2.3, by composite board thickness in monolayer, carbon fibre composite crack propagation energy, elastic modelling quantity and Poisson's ratio variable substitutes into formula (1) computing formula, obtains the critical axial cutting force for producing lamination defect；

Step 3, the borehole axial cutting force for calculating the steady drilling starting stage；

Step 3.1, carry out laminated construction drilling orthogonal test, drill into the steady drilling stage it is initial when, use Dynamometer is gathered, measures every group of borehole axial cutting force of experiment, by observing the variation tendency of cutting force in boring procedure, really Determine carbon fibre composite and titanium alloy laminated construction drilling reach the steady drilling starting stage standard be drilling 5 or 6 Hole；

Step 3.2, by the axial cutting force Data Analysis Services to step 3.1, set up with drill head helix angle, drift angle, The related carbon fibre composite drilling cutting force empirical equation of outer rim relief angle, drilling cutting speed, the drilling amount of feeding, such as formula (2) shown in；

Wherein, F_zsiIt is the borehole axial cutting force of carbon fibre composite drilling steady drilling starting stage, β is drill bit Helical angle, α_rIt is drill bit outer rim relief angle,It is drill head apical angle, Vc is drilling cutting speed, and fr is drilling feed of every rotation；

Step 3.3, the borehole axial cutting force that the steady drilling starting stage is calculated by formula (2)；

Step 4, calculate with drilling number change the whole steady drilling stage dynamic realtime axial cutting force；

Step 4.1, the continuous drilling multi-well experiment of laminated construction is carried out, using the real-time axle in each hole of dynamometer measurement drilling To cutting force；

Step 4.2, by Data Analysis Services, the relation curve of axial cutting force and drilling quantity is obtained, based on steady The borehole axial cutting force of drilling starting stage, sets up whole steady drilling stage cutting force and is closed with the Linear Mapping of drilling quantity It is formula, as shown in formula (3)；

F_Nb=1.136N+102.927+F_zsi (3)

Wherein, F_NbIt is boring procedure dynamic realtime axial cutting force, N is drilling hole amount；

Step 4.3, by being input into different drilling quantity, calculate the axial cutting force of dynamic realtime；

The dynamic realtime cutting force F of step 4.4, comparison step 4.3_NbWith the critical cutting force F of step 1_A, judge whether to produce Layer defects estranged；

If F_NbLess than F_A, then lamination defect is not produced, increase by 1 drilling quantity, return to step 4.3；If F_NbIt is more than Or equal to F_A, then lamination defect is produced, perform step 5；

Step 5, prediction lamination defect regional diameter and maximum drilling quantity；

Step 5.1, the continuous drilling multi-well experiment of laminated construction is carried out, using the multiple material lamination defect region of ultrasound examination Area, while using the axial cutting force of dynamometer measurement drilling；

Step 5.2, by data processing, using economics analysis method, set up lamination defect regional diameter forecast analysis mould Type, shown in the forecast analysis model such as formula (4)；

Wherein, D_mIt is lamination defect region maximum gauge, D is bore diameter；

Step 5.3, by forecast analysis modular form (4), the diameter in prediction lamination defect region, and acquisition meets step 1 The maximum drilling quantity of lamination defect requirement.

As shown from the above technical solution, the beneficial effects of the present invention are：The CFRP that the present invention is provided and titanium alloy lamination Structure drill lamination defect Forecasting Methodology, can under the conditions of Present Borehole, analyze drilling to during different drilling quantity whether Meet the analyzing defect standard of setting, and the maximum drilling quantity for meeting lamination defect standard can be given, effectively improve drilling Cutting-tool's used life and laminated construction drilling qualification rate, prevent because exceed lamination defect standard caused by part rejection, Save production cost.

Brief description of the drawings

Fig. 1 is the Forecasting Methodology flow of CFRP provided in an embodiment of the present invention and titanium alloy laminated construction drilling lamination defect Figure；

Fig. 2 is the graph of relation of plateau borehole axial cutting force provided in an embodiment of the present invention and drilling quantity；

Fig. 3 is the schematic diagram that drilling provided in an embodiment of the present invention produces lamination defect.

Specific embodiment

With reference to the accompanying drawings and examples, specific embodiment of the invention is described in further detail.Hereinafter implement Example is not limited to the scope of the present invention for illustrating the present invention.

The method that the present invention is tested using economics analysis and drilling, analytical Calculation carbon fibre composite produces lamination defect Axis critical force, set up T300 carbon fibre composites and TC6 titanium alloy laminated construction lamination defect evaluation analysis model, flat Steady drilling starting stage axial cutting force computation model and axial cutting force are proposed with the mapping relations model of drilling number change A kind of prediction analysis method of laminated construction boring procedure carbon fibre composite lamination defect, joins according to current drill bit structure The conditions such as number, drill process parameter and drilling quantity, judge that can boring procedure produce lamination defect, and forecast analysis layering The maximum gauge of defect area.

By taking T300 carbon fibre composites and TC6 titanium alloy laminated construction boring procedures as an example, there is provided a kind of CFRP and titanium Alloy stack structure drills the Forecasting Methodology of lamination defect, drilling sequences of the laminated construction and first to process T300 composites Sheet material, post-processing TC6 titanium alloy plates.As shown in figure 1, the method for the present embodiment is as described below.

Step 1, setting lamination defect region maximum gauge allowable are 6mm.

Step 2, the critical axial cutting force that carbon fibre composite produces lamination defect is calculated, specific method is：

Step 2.1, based on economics analysis method, set up the critical axial direction that carbon fibre composite drilling produces lamination defect Cutting force computing formula, as shown in formula (1).

Wherein, F_AIt is borehole axial cutting force, G_ICIt is the extension energy of carbon fibre composite crackle in unit area, E It is the modulus of elasticity in static bending, h is carbon fibre composite thickness in monolayer, and v is Poisson's ratio；

Step 2.2, using super depth-of-field microscope observation, measurement composite board, obtain carbon fibre composite sheet material Thickness in monolayer；In the present embodiment, tested by measuring, the thickness in monolayer for measuring T300 composite boards is 0.297mm.

Step 2.3, by carbon fibre composite sheet material thickness in monolayer, carbon fibre composite crack propagation energy, elasticity Modulus and Poisson's ratio variable substitute into formula (1) computing formula, obtain the critical axial cutting force for producing lamination defect.

By associated materials handbook, the correlation properties for obtaining T300 composites are：Crack propagation energy is 285J/m²、 Elastic modelling quantity is 115Gpa, Poisson's ratio is 0.34, and the T300 critical axial cutting forces of composite lamination defect being calculated are 159.852N。

Step 3, the borehole axial cutting force for calculating steady drilling starting stage, specific method is：

Step 3.1, carry out laminated construction drilling orthogonal test, drill into the steady drilling stage it is initial when, use Dynamometer is gathered, measures every group of borehole axial cutting force of experiment.In the present embodiment, cutting force change becomes in observation boring procedure Gesture, it is found that cutting force is changed into steadily increasing state since the 5th hole of drilling, it is thus determined that carbon fibre composite and titanium are closed The standard that golden laminated construction drilling reaches the steady drilling starting stage is 5 holes of drilling.In specific implementation, at the beginning of reaching steady drilling The standard in stage beginning can also be set as 6 holes of drilling.

Step 3.2, cutting force Data Analysis Services are measured by step 3.1, set up and drill head helix angle, drift angle, outer The related carbon fibre composite drilling cutting force empirical equation of edge relief angle, drilling cutting speed, the drilling amount of feeding, such as formula (2) It is shown.

Wherein, F_zsiIt is the borehole axial cutting force of carbon fibre composite drilling steady drilling starting stage, β is drill bit Helical angle, α_rIt is drill bit outer rim relief angle,It is drill head apical angle, Vc is drilling cutting speed, and fr is drill feed amount.

Step 3.3, the borehole axial cutting force that the steady drilling starting stage is calculated by formula (2).

In the present embodiment, a diameter of 6mm of drilling drill bit, helical angle are 25 degree, outer rim relief angle is 12 degree, drift angle is 140 degree, cutter material be K6UF (hard alloy), drilling cutting speed be 30m/min, the drilling amount of feeding be 0.03mm/min. The axial cutting force of steady drilling starting stage is 108.626N after formula (2) is calculated 5 holes of drilling.

Step 4, dynamic realtime axial cutting force with the whole steady drilling stage of drilling number change is calculated, specific side Method is：

Step 4.1, drilling experiment is carried out according to the drilling condition of step (2), carry out the laminated construction porous examination of continuous drilling Test, using the real-time axial cutting force in each hole of dynamometer measurement drilling, main announcement cutting force drilling quantity is increased dynamic State Changing Pattern.

Step 4.2, by Data Analysis Services, the relation curve of axial cutting force and drilling quantity is obtained, based on steady The borehole axial cutting force of drilling starting stage, sets up whole steady drilling stage cutting force and is closed with the Linear Mapping of drilling quantity It is formula, as shown in formula (3).

F_Nb=1.136N+102.927+F_zsi (3)

Wherein, F_NbIt is boring procedure dynamic realtime axial cutting force, N is drilling hole amount.

Step 4.3, by being input into different drilling quantity, calculate dynamic realtime axial cutting force.In the present embodiment, steadily Stage borehole axial cutting force is as shown in Figure 2 with the graph of relation of drilling quantity.

The cutting force measured in step 4.1 is that, for setting up formula (3), and the meaning of step 4.3 is to be surveyed again Amount experiment, can directly calculate dynamic cutting force by formula (3).

The dynamic realtime cutting force F of step 4.4, comparison step 3_NbWith the critical cutting force F of step 1_A, judge whether to produce Lamination defect；

If F_NbLess than F_A, then lamination defect is not produced, increase drilling quantity, continue executing with step 3.3；If F_NbIt is more than Or equal to F_A, then lamination defect is produced, perform step 4.In the present embodiment, by calculating simultaneously observation analysis, find in drilling extremely After 51 holes, there is lamination defect in T300 carbon fibre composites, as shown in Figure 3.By formula (3) calculating drilling now Axial cutting force is 160.863N, more than the 159.852N for producing the critical axial cutting force of lamination defect.

Step 5, prediction lamination defect regional diameter and maximum drilling quantity；

Step 5.1, the continuous drilling multi-well experiment of laminated construction is carried out, using the multiple material lamination defect region of ultrasound examination Area, while using the axial cutting force of dynamometer measurement drilling, the main maximum lamination defect diameter that discloses cuts with dynamic The dynamic rule of power；

Step 5.2, by data processing, using economics analysis method, set up lamination defect regional diameter forecast analysis mould Type, shown in the forecast analysis model such as formula (4)；

Wherein, D_mIt is the maximum gauge in lamination defect region, D is bore diameter；

Step 5.3, by forecast analysis modular form (4), the lamination defect regional diameter for being calculated the hole of drilling the 51st is 5.976mm, the lamination defect regional diameter that the lamination defect regional diameter in the hole of drilling the 52nd is is 6.278mm, is set more than step 1 The lamination defect region allowable maximum gauge put, therefore maximum drilling quantity is 50 holes.

CFRP and the Forecasting Methodology of titanium alloy laminated construction drilling lamination defect that the present invention is provided, can be in Present Borehole Under the conditions of, whether meet the analyzing defect standard of setting when analysis drilling is to different drilling quantity, and satisfaction layering can be provided The maximum drilling quantity of defect standard, effectively improves the qualification rate of drilling cutting-tool's used life and laminated construction drilling, prevents Because more than part rejection caused by lamination defect standard, saving production cost.

Finally it should be noted that：The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；Although The present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those within the art that：It still may be used Modified with to the technical scheme described in previous embodiment, or which part or all technical characteristic are equal to Replace；And these modifications or replacement, the essence of appropriate technical solution is departed from the model that the claims in the present invention are limited Enclose.

Claims (1)

1. a kind of CFRP and titanium alloy laminated construction drill the Forecasting Methodology of lamination defect, it is characterised in that：The method is specifically wrapped Include following steps：

Step 1, setting lamination defect requirement, i.e., lamination defect region maximum gauge allowable；

Step 2, the critical axial cutting force for calculating carbon fibre composite generation lamination defect；

Step 2.1, based on economics analysis method, set up the critical axially cutting that carbon fibre composite drilling produces lamination defect Power computing formula, as shown in formula (1)；

$F_A=\mathrm{\π}{\[\frac{8G_{IC}{\mathrm{Eh}}^3}{3(1-v^2)}\]}^{1/2}---\left(1\right)$

Wherein, F_AIt is borehole axial cutting force, G_ICIt is the extension energy of carbon fibre composite crackle in unit area, E is curved Modulus in elasticity in bending, h is carbon fibre composite thickness in monolayer, and v is Poisson's ratio；

Step 2.2, using super depth-of-field microscope observation, measurement composite board, obtain carbon fibre composite sheet material individual layer Thickness；

Step 2.3, by composite board thickness in monolayer, carbon fibre composite crack propagation energy, elastic modelling quantity and Poisson Formula (1) computing formula is substituted into than variable, the critical axial cutting force for producing lamination defect is obtained；

Step 3, the borehole axial cutting force for calculating the steady drilling starting stage；

Step 3.1, carry out laminated construction drilling orthogonal test, drill into the steady drilling stage it is initial when, using dynamometry Instrument is gathered, measures every group of borehole axial cutting force of experiment, and carbon fibre composite and the drilling of titanium alloy laminated construction reach flat The standard of steady drilling starting stage is 5 or 6 holes of drilling；

Step 3.2, by the axial cutting force Data Analysis Services to step 3.1, set up and drill head helix angle, drift angle, outer rim The related carbon fibre composite drilling cutting force empirical equation of relief angle, drilling cutting speed, the drilling amount of feeding, such as formula (2) institute Show；

Wherein, F_zsiIt is the borehole axial cutting force of carbon fibre composite drilling steady drilling starting stage, β is drill bit spiral Angle, α_rIt is drill bit outer rim relief angle,It is drill head apical angle, Vc is drilling cutting speed, and fr is drilling feed of every rotation；

Step 3.3, the borehole axial cutting force that the steady drilling starting stage is calculated by formula (2)；

Step 4, calculate with drilling number change the whole steady drilling stage dynamic realtime axial cutting force；

Step 4.1, the continuous drilling multi-well experiment of laminated construction is carried out, cut using the real-time axial direction in each hole of dynamometer measurement drilling Cut power；

Step 4.2, by Data Analysis Services, the relation curve of axial cutting force and drilling quantity is obtained, based on steady drilling The borehole axial cutting force of starting stage, sets up whole steady drilling stage cutting force public with the linear mapping relation of drilling quantity Formula, as shown in formula (3)；

F_Nb=1.136N+102.927+F_zsi (3)

Wherein, F_NbIt is boring procedure dynamic realtime axial cutting force, N is drilling hole amount；

Step 4.3, by being input into different drilling quantity, calculate the axial cutting force of dynamic realtime；

The dynamic realtime cutting force F of step 4.4, comparison step 4.3_NbWith the critical cutting force F of step 1_A, judge whether to produce and divide Layer defects；

If F_NbLess than F_A, then lamination defect is not produced, increase drilling quantity, continue executing with step 4.3；If F_NbMore than or wait In F_A, then lamination defect is produced, perform step 4；

Step 5, prediction lamination defect regional diameter and maximum drilling quantity；

Step 5.1, the continuous drilling multi-well experiment of laminated construction is carried out, using the face in the multiple material lamination defect region of ultrasound examination Product, while using the axial cutting force of dynamometer measurement drilling；

Step 5.2, by data processing, using economics analysis method, set up lamination defect regional diameter forecast analysis model, should Shown in forecast analysis model such as formula (4)；

$D_m=\sqrt{{(0.0267\×(F_{Nb}-F_A)*D)}^2+D^2}---\left(4\right)$

Wherein, D_mIt is lamination defect region maximum gauge, D is bore diameter；

Step 5.3, by forecast analysis modular form (4), the diameter in prediction lamination defect region, and obtain and meet step 1 and be layered The maximum drilling quantity of defect requirement.