CN105808507A - Comprehensive analysis method for weld seam appearance of laser welding parts under multiple characteristic indexes - Google Patents

Abstract

The invention provides a comprehensive analysis method for weld seam appearance of laser welding parts under multiple characteristic indexes. The method comprises the steps that a matrix of the multiple characteristic indexes of the weld seam appearance is constructed according to weld seam appearance characteristic indexes obtained under different welding processing technology parameters, normalization processing is conducted, weight values of all the characteristic indexes of the weld seam appearance are determined through a comprehensive weight method integrating subjective information and objective information, and a comprehensive weight vector integrating different information sources is obtained; a normative weighting matrix is constructed, a positive ideal solution and a negative ideal solution of the normative weighting matrix are calculated, and Euclidean distances of the weld seam appearance of all the welding parts and the positive ideal solution and the negative ideal solution are calculated respectively; comprehensive analysis coefficients of all the welding parts are calculated, and the welding parts are arranged according to the sequence from big to small according to the comprehensive analysis coefficients. A multi-attribute sorting result is more objective and reasonable, and therefore an optimal laser welding scheme is sorted out.

Description

A kind of comprehensive analysis method under the many characteristic indexs of laser welded parts seam center

Technical field

The invention belongs to laser weld program decisions technical field, be specifically related to the comprehensive analysis method under a kind of many characteristic indexs of laser welded parts seam center.

Background technology

When laser weld schemes synthesis demonstration or concept phase, typically require and adopt suitable strategy, according to analysis indexes specific in the laser welded parts seam center that alternative multiple welding schemes actually obtain (such as fusion penetration, molten width, pile high) optimum scheme comparison, but be mutually linked between the indices obtained, influence each other, complicated, often there is certain dependency or inharmonic situation in some criterion of laser weld scheme, this essence is a Multiple Attribute Decision Problems, the reasonability of multiple attribute decision making (MADM) result and each attribute distributed weight size has substantial connection.

The method that present analysis laser weld scheme is excellent mainly includes following several: (1) policymaker uses for reference expertise and gives certain proportion to specific attribute in laser welded parts seam center, this tax power method simple and fast, interpretability are strong, but the subjective impact by analysis personnel is big, have subjective random；(2) knowledge such as policymaker's applied optics, investigates the quantity of information of each attribute in laser welded parts seam center, determines that weight vectors, the method have mathematical theory basis by analysis indexes, can reflected sample raw information, but result easily deviates reality；(3) certain mode is utilized subjective weights and Objective Weight to be combined in a certain way, the shortcoming that the method can overcome subjective weights and Objective Weight, but it is bigger directly to adopt the normalization method of multiplicative synthesis to may result in big person, the multiplier effect that little person is less, it is difficult to objective, reasonably pick out optimum laser weld scheme.

Summary of the invention

Defect that the purpose of the present invention is contemplated to overcome above-mentioned prior art to exist and the comprehensive analysis method under a kind of many characteristic indexs of laser welded parts seam center is proposed, make the result that many attributes sort more objective, reasonable, thus picking out the laser weld scheme of optimum.

To achieve these goals, the present invention proposes the comprehensive analysis method under a kind of many characteristic indexs of laser welded parts seam center, comprises the following steps:

S1: determine seam center characteristic index；Include but not limited to weld seam left part length, weld seam right part length, weld seam upper and lower end length, weld penetration；

S2: build seam center characteristic index matrixWherein, M is the required weldment number analyzed, and N is seam center characteristic index number, a_ijRepresent the jth desired value of i-th weldment；

S3: to matrix A normalized, it is thus achieved that normalized seam center characteristic index matrixWherein,N is the normalized value of the jth seam center characteristic index of i-th weldment；

S4: determine the weight vectors of each characteristic index of seam center: concrete sub-step is as follows:

S41: collect subjective information, obtain each characteristic index weight vectors of seam center；

S42: collect objective information, obtain the weight vectors of each characteristic index of seam center；

Definition λ=[λ₁,λ₂,λ_p..., λ_T], representing the equilibrium index under different information source, p is the number of information source, and λ is 1 dimension T column vector, and T is the sum of information source；Equilibrium index λ is for weighing the degree of stability of different aforementioned sources:

${\mathrm{\λ}}_p=d_p/\underset{p=1}{\overset{T}{\Σ}}{d}_p,$

$d_p=\frac{\underset{p=1}{\overset{T}{\Σ}}\underset{q=1,p\≠q}{\overset{T}{\Σ}}norm(w_p,w_q)}{\underset{q=1,q\≠p}{\overset{T}{\Σ}}norm(w_p,w_q)};$

Wherein,For the weight vectors w under pth information source_p, and except w_pInformation source w in addition_qThe summation of Euclidean distance between the weight vectors obtained, norm represents and seeks Euclidean distance, w_pWith w_qBeing 1 row N column vector, the span of p and q is p≤T；q≤T.

S5: calculate the comprehensive weight vector after integrated different information source

S6: structure specification weighting matrix

S7: obtain positive ideal solution c⁺With minus ideal result c^-, wherein,

Positive ideal solution:

Minus ideal result:

S8: calculate each weldment seam center characteristic index and positive Euclidean distance D between ideal solution and minus ideal result respectively_i ⁺And D_i ^-, wherein,

${D_i}^{+}=\sqrt{\underset{j=1}{\overset{n}{\Σ}}{c}_{ij}-{c_j}^{{+}^2}},i=1,2,\mathrm{...},M$

${D_i}^{-}=\sqrt{\underset{j=1}{\overset{n}{\Σ}}{c}_{ij}-{c_j}^{{-}^2}},i=1,2,\mathrm{...},M$

S9: what calculate each weldment comprehensively analyzes coefficient k_i, k_i=D_i ^-/(D_i ⁺+D_i ^-), and press k_iDescending arrangement, obtains the sequence value vector K under weldment seam center many signs indicator conditions；In sequence value vector K, each sequence value numbering is more forward, it was shown that the comprehensive pattern of weld seam of this weldment is more good.

Further, in the step S4 of described comprehensive analysis method, described subjective information is from expert estimation or analytic hierarchy process (AHP).

Further, in the step S4 of described comprehensive analysis method, objective information adopts VC Method and comentropy method to obtain.

The invention has the beneficial effects as follows: according to the many characteristic indexs of laser welded parts seam center, propose comprehensive subjective weight method and the objective weight method of a kind of reasonable science, by defining the equilibrium index of subjective weight and objective weight, weigh the degree of stability of subjective weight and objective weight, and calculated the comprehensive weight method simultaneously considering subjective weight and objective weight by step 4.The subjective impact by analyzing subjective weight can be overcome big, there is subjective random subjective method and the shortcoming easily deviateing actual objective weight method, can according to the many characteristic indexs of laser welded parts seam center, make the result that the many attributes of seam center sort more objective, reasonable, thus picking out the laser weld scheme of optimum.

Accompanying drawing explanation

Fig. 1 is the comprehensive analysis method flow chart under the many characteristic indexs of laser welded parts seam center of the present invention.

Detailed description of the invention

In order to make the purpose of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein is only in order to explain the present invention, is not intended to limit the present invention.As long as just can be mutually combined additionally, technical characteristic involved in each embodiment of invention described below does not constitute conflict each other.

As it is shown in figure 1, the comprehensive analysis method under the many characteristic indexs of laser welded parts seam center of the present invention, specifically comprise the following steps that

S1: obtain the seam center under 25 groups of difference technique for welding parameters and characterize index (bottom weld seam left end length, weld seam right-hand member length, weld seam wide, weld seam top width)；

The seam center obtaining laser welded parts according to laser welding process parameter under various combination (speed of welding (WS), wire feed rate (WF), spacing) is as shown in table 1 below:

In table 1, wide bottom weld seam left end length, weld seam right-hand member length, weld seam, weld seam top width is the selected weldquality characteristic index of present embodiment.

Table 1

S2: build under different working process parameter, seam center many signs exponential matrix.Owing to have chosen wide, wide 4 characteristic indexs in weld seam top bottom weld seam left end length, weld seam right-hand member length, weld seam, the exponential matrixs that characterize are that 25 row 4 arrange more.

$\begin{array}{c}A=\[\\ \begin{array}{cccc}4.12& 0.61& 2.48& 3.43\\ 3.61& 0.95& 2.07& 2.55\\ 4.07& 1.26& 1.79& 2.37\\ 4.2& 1.03& 1.98& 3.32\\ 3.8& 1.25& 2.26& 3.1\\ 3.84& 3.11& 2.29& 2.38\\ 3.71& 0.96& 1.93& 2.56\end{array}\end{array}$

$\begin{array}{c}\begin{array}{cccc}4& 0.93& 1.93& 2.88\\ 3.88& 1.24& 1.86& 2.62\\ 3.82& 0.83& 1.86& 2.61\\ 3.7& 0.85& 2.53& 2.73\\ 3.63& 1.28& 1.72& 2.59\\ 3.65& 1.01& 2.94& 3.02\\ 3.42& 1.03& 1.33& 2.36\\ 3.64& 1.11& 1.68& 2.46\\ 3.24& 1.41& 0.92& 1.91\\ 3.62& 1.3& 1.76& 2.37\\ 3.5& 1.09& 1.33& 2.1\\ 3.41& 1.12& 1.6& 1.92\\ 3.37& 1.27& 1.81& 2.07\\ 3.5& 1.35& 1.24& 2.4\\ 2.23& 1.01& 1.25& 3.44\\ 3.31& 1.12& 1.443& 1.92\\ 3.26& 1.24& 1.12& 2.16\\ 2.41& 0.86& 2.07& 2.39\end{array}\\ \];\end{array}$

S3: butt welded seam pattern many signs exponential matrix A normalized, it is thus achieved that normalized seam center characteristic index matrix B, wherein,

$\begin{array}{c}B=\[\\ \begin{array}{cccc}0.0463& 0.0209& 0.0549& 0.0539\\ 0.0406& 0.0325& 0.0458& 0.0401\\ 0.0458& 0.0431& 0.0396& 0.0372\\ 0.0472& 0.0352& 0.0438& 0.0522\\ 0.0427& 0.0428& 0.0500& 0.0487\\ 0.0432& 0.1064& 0.0507& 0.0374\\ 0.0417& 0.0329& 0.0427& 0.0402\\ 0.0450& 0.0318& 0.0427& 0.0452\\ 0.0436& 0.0424& 0.0412& 0.0412\\ 0.0430& 0.0284& 0.0412& 0.0410\\ 0.0416& 0.0291& 0.0560& 0.0429\\ 0.0408& 0.0438& 0.0381& 0.0407\\ 0.0410& 0.0346& 0.0651& 0.0474\\ 0.0385& 0.0352& 0.0294& 0.0371\\ 0.0409& 0.0380& 0.0372& 0.0386\\ 0.0364& 0.0483& 0.0204& 0.0300\\ 0.0407& 0.0445& 0.0389& 0.0372\end{array}\end{array}$

$\begin{array}{c}\begin{array}{cccc}0.0394& 0.0373& 0.0294& 0.0330\\ 0.0383& 0.0383& 0.0354& 0.0302\\ 0.0379& 0.0435& 0.0401& 0.0325\\ 0.0394& 0.0462& 0.0274& 0.0377\\ 0.0251& 0.0346& 0.0277& 0.0540\\ 0.0372& 0.0383& 0.0319& 0.0302\\ 0.0367& 0.0424& 0.0248& 0.0339\\ 0.0271& 0.0294& 0.0458& 0.0375\end{array}\\ \];\end{array}$

S4: adopt combination weights method to determine the weighted value of each sign index of seam center for integrated subjectivity and objective information, specifically comprise the following steps that

S41: collect subjective information source: such as expert estimation or analytic hierarchy process (AHP)；The present embodiment adopts expert graded commonly used in the art, and in actual welding process, good left end length, weld seam right-hand member appearance are more difficult to obtain in weld seam for width, weld seam top bottom weld seam, therefore take: W₁=[0.30.30.250.15]；

S42: collect objective information source: usual method is to select seam center each VC Method characterizing index and information Entropy Method；The present embodiment adopts VC Method and information Entropy Method

Employing VC Method obtains: W₂=[0.12810.38260.26360.1758]；

Employing information Entropy Method obtains: W₃=[0.07640.49030.30230.1310]；

S43: determine equilibrium index (λ): norm (W₁-W₂)=0.2615；norm(W₁-W₃)=0.2988；norm(W₂-W₃)=0.4858. λ=[0.2743,0.4135,0.3122]；

S5: obtain the comprehensive weight vector after integrated different information sourceW=[0.1591,0.3936,0.2720,0.1547]；

S6: structure specification weighting matrix C,

$C=\[$

$\begin{array}{c}\begin{array}{cccc}0.0074& 0.0082& 0.0149& 0.0083\\ 0.0065& 0.0128& 0.0125& 0.0062\\ 0.0073& 0.0170& 0.0108& 0.0058\\ 0.0075& 0.0139& 0.0119& 0.0081\\ 0.0068& 0.0168& 0.0136& 0.0075\\ 0.0069& 0.0419& 0.0138& 0.0058\\ 0.0066& 0.0129& 0.0116& 0.0062\\ 0.0072& 0.0125& 0.0116& 0.0070\\ 0.0069& 0.0167& 0.0112& 0.0064\\ 0.0068& 0.0112& 0.0112& 0.0063\\ 0.0066& 0.0114& 0.0152& 0.0066\\ 0.0065& 0.0172& 0.0104& 0.0063\\ 0.0065& 0.0136& 0.0177& 0.0073\\ 0.0061& 0.0139& 0.0080& 0.0057\\ 0.0065& 0.0150& 0.0101& 0.0060\\ 0.0058& 0.0190& 0.0055& 0.0046\\ 0.0065& 0.0175& 0.0106& 0.0058\\ 0.0063& 0.0147& 0.0080& 0.0051\\ 0.0061& 0.0151& 0.0096& 0.0047\\ 0.0060& 0.0171& 0.0109& 0.0050\\ 0.0063& 0.0182& 0.0075& 0.0058\\ 0.0040& 0.0136& 0.0075& 0.0084\\ 0.0059& 0.0151& 0.0087& 0.0047\\ 0.0058& 0.0167& 0.0067& 0.0052\\ 0.0043& 0.0116& 0.0125& 0.0058\end{array}\\ \];\end{array}$

S7: find out positive ideal solution and minus ideal result, wherein, positive ideal solution and minus ideal result are obtained by following method:

Positive ideal solution:

c⁺=[0.00750.04190.01770.0177],

Minus ideal result:

c^-=[0.00400.00820.00550.0046]；

S8: calculate the seam center of each welding number of packages and positive Euclidean distance D between ideal solution and minus ideal result respectively_i ⁺And D_i ^-, wherein D_i ⁺And D_i ^-It is calculated by this formula:

${D_i}^{+}=\sqrt{\underset{j=1}{\overset{n}{\Σ}}{c}_{ij}-{c_j}^{{+}^2}},i=1,2,\mathrm{...},25,{D_i}^{-}=\sqrt{\underset{j=1}{\overset{n}{\Σ}}{c}_{ij}-{c_j}^{{-}^2}},i=1,2,\mathrm{...},25$

$\begin{array}{c}{D_i}^{+}=\[\\ \begin{array}{ccccccccc}0.0351& 0.0472& 0.0549& 0.0627& 0.0684& 0.0685& 0.0755& 0.0820& 0.0867\\ 0.0929& 0.0984& 0.1023& 0.1065& 0.1111& 0.1152& 0.1185& 0.1218& 0.1257\\ 0.1294& 0.1325& 0.1355& 0.1391& 0.1425& 0.1456& 0.1493\],& & \end{array}\end{array}$

$\begin{array}{c}{D_i}^{-}=\[\\ \begin{array}{ccccccccc}0.0106& 0.0133& 0.0160& 0.0187& 0.0224& 0.0395& 0.0402& 0.0408& 0.0421\\ 0.0425& 0.0432& 0.0445& 0.0459& 0.0463& 0.0471& 0.0481& 0.0493& 0.0498\\ 0.0505& 0.0516& 0.0525& 0.0529& 0.0534& 0.0541& 0.0544\];& & \end{array}\end{array}$

S9: what calculate each weld seam comprehensively analyzes coefficient k_i, k_i=D_i ^-/(D_i ⁺+D_i ^-),

$\begin{array}{c}k=\[\\ \begin{array}{ccccccccc}0.2328& 0.2197& 0.2255& 0.2299& 0.2465& 0.3657& 0.3471& 0.3322& 0.3269\\ 0.3138& 0.3051& 0.3031& 0.3011& 0.2943& 0.2904& 0.2885& 0.2881& 0.2837\\ 0.2805& 0.2800& 0.2793& 0.2754& 0.2727& 0.2708& 0.2672\]& & \end{array}\end{array}$

Coefficient magnitude order is comprehensively analyzed by each weld seam, arrange its number order k, the integrated ordered quality of weld seam can be obtained and be followed successively by (# represents welding seam No): K=[6#7#8#9#10#11#12#13#14#15#16#17#18#19#20#21#22#23#24#25# 5#1#4#3#2#], as can be seen from Table 1, bottom the weld seam left end length of weld seam 6, weld seam right-hand member length, weld seam, the measurement result of wide, wide 4 characteristic indexs in weld seam top is relative to other weld seam indexs, it is in the middle part of interval, more meets and comprehensively select excellent result.

The method of the present invention, comprehensive subjective weight method and objective weight method, the subjective impact by analyzing subjective weight can be overcome big, there is subjective random subjective method and the shortcoming easily deviateing actual objective weight method, can according to the many characteristic indexs of laser welded parts seam center, make the result that the many attributes of seam center sort more objective, reasonable, thus picking out the laser weld scheme of optimum.

The ultimate principle of the present invention, principal character and advantages of the present invention have more than been shown and described.Skilled person will appreciate that of the industry; the present invention is not restricted to the described embodiments; described in above-described embodiment and description is that principles of the invention is described; without departing from the spirit and scope of the present invention; the present invention also has various changes and modifications, and these changes and improvements both fall within the scope of protection of present invention.

Claims (3)

1. the comprehensive analysis method under the many characteristic indexs of laser welded parts seam center, it is characterised in that comprise the following steps:

S1: determine seam center characteristic index；

S2: build seam center characteristic index matrixWherein, M is the required weldment number analyzed, and N is seam center characteristic index number, including weld seam left part length, weld seam right part length, weld seam upper and lower end length, weld penetration；a_ijRepresent the jth desired value of i-th weldment；

S3: to matrix A normalized, it is thus achieved that normalized seam center characteristic index matrixWherein,Normalized value for the jth seam center characteristic index of i-th weldment；

S4: determine the weight vectors of each characteristic index of seam center: concrete sub-step is as follows:

S41: collect subjective information, obtain each characteristic index weight vectors of seam center；

S42: collect objective information, obtain the weight vectors of each characteristic index of seam center；

S43: definition λ=[λ₁, λ₂..., λ_p..., λ_T] representing the equilibrium index under different information source, p is the number of information source, and λ is 1 dimension T column vector, and T is the sum of information source；Equilibrium index λ is for weighing the degree of stability of different aforementioned sources:

Wherein

Wherein,For the weight vectors w under pth information source_p, and except w_pInformation source w in addition_qThe summation of Euclidean distance between the weight vectors obtained, norm represents and seeks Euclidean distance, w_pWith w_qBeing 1 row N column vector, the span of p and q is p≤T；q≤T.

S5: calculate the comprehensive weight vector after integrated different information source

S6: structure specification weighting matrix

S7: obtain positive ideal solution c⁺With minus ideal result c^-, wherein,

Positive ideal solution:

Minus ideal result:

S8: calculate each weldment seam center characteristic index and positive Euclidean distance D between ideal solution and minus ideal result respectively_i ⁺And D_i ^-, wherein,

${D_i}^{+}=\sqrt{\underset{j=1}{\overset{n}{\Σ}}{c}_{ij}-{c_j}^{{+}^2}},i=1,2,\mathrm{...},M$

${D_i}^{-}=\sqrt{\underset{j=1}{\overset{n}{\Σ}}{c}_{ij}-{c_j}^{{-}^2}},i=1,2,\mathrm{...},M$

S9: what calculate each weldment comprehensively analyzes coefficient k_i, k_i=D_i ^-/(D_i ⁺+D_i ^-), and press k_iDescending arrangement, obtains the sequence value vector K under weldment seam center many signs indicator conditions；The sequence value numbering more leaned in sequence value vector K, the comprehensive pattern of weld seam of the weldment of its correspondence is more good.

2. the comprehensive analysis method under a kind of many characteristic indexs of laser welded parts seam center according to claim 1, it is characterised in that in step S4, described subjective information is from expert estimation or analytic hierarchy process (AHP).

3. comprehensive analysis method according to claim 2, it is characterised in that in step S4, objective information adopts VC Method and comentropy method to obtain.