CN1324160C - Plasma spraying method for improving fatigue performance of welded structure - Google Patents
Plasma spraying method for improving fatigue performance of welded structure Download PDFInfo
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- CN1324160C CN1324160C CNB2005100132849A CN200510013284A CN1324160C CN 1324160 C CN1324160 C CN 1324160C CN B2005100132849 A CNB2005100132849 A CN B2005100132849A CN 200510013284 A CN200510013284 A CN 200510013284A CN 1324160 C CN1324160 C CN 1324160C
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- 238000000034 method Methods 0.000 title claims abstract description 28
- 239000011248 coating agent Substances 0.000 claims abstract description 57
- 238000000576 coating method Methods 0.000 claims abstract description 57
- 239000000843 powder Substances 0.000 claims abstract description 17
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 10
- 230000008569 process Effects 0.000 claims abstract description 10
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 9
- 229910003266 NiCo Inorganic materials 0.000 claims abstract description 4
- 229910052723 transition metal Inorganic materials 0.000 claims abstract description 4
- 150000003624 transition metals Chemical class 0.000 claims abstract description 4
- 238000002360 preparation method Methods 0.000 claims abstract description 3
- 229910000831 Steel Inorganic materials 0.000 claims description 12
- 238000005507 spraying Methods 0.000 claims description 12
- 239000010959 steel Substances 0.000 claims description 12
- 230000015572 biosynthetic process Effects 0.000 claims 1
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- 238000007747 plating Methods 0.000 description 33
- 229910052751 metal Inorganic materials 0.000 description 15
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- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 11
- 238000009661 fatigue test Methods 0.000 description 10
- 238000012545 processing Methods 0.000 description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 6
- 239000004411 aluminium Substances 0.000 description 6
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Abstract
本发明公开了一种改善焊接结构疲劳性能的等离子喷涂法，采用等离子喷涂工艺在焊缝表面喷涂涂层，该喷涂涂层的制备方法包括以下步骤：a.将试样焊缝处进行吹砂处理；b.在焊缝表面等离子喷涂粘结底层，所述底层材料选自Ni/Al、Ni/Cr或MCrAlY，M为过渡金属Fe、Ni、Co或NiCo，底层厚度为0.03～0.07mm；c.将粉未等离子喷涂在焊缝表面形成表面涂层，涂层厚度为0.8～1.2mm。本发明通过在接头焊趾处等离子喷涂低弹性模量涂层的方法改善焊接结构的疲劳性能，接头焊趾处等离子喷涂层可改善截面形状变化，降低该处的应力集中，提高焊接结构的疲劳强度；(二)与焊态试件相比，本发明的等离子喷涂试件的疲劳强度提高25.9%，火焰喷涂试件仅提高9.7%。The invention discloses a plasma spraying method for improving the fatigue performance of a welded structure. The plasma spraying process is used to spray a coating on the surface of a weld. The preparation method of the sprayed coating comprises the following steps: a. performing sandblasting on the weld of a sample Treatment; b. Plasma spraying and bonding the bottom layer on the surface of the weld, the bottom layer material is selected from Ni/Al, Ni/Cr or MCrAlY, M is a transition metal Fe, Ni, Co or NiCo, and the thickness of the bottom layer is 0.03-0.07mm; c. Plasma spray the powder on the surface of the weld to form a surface coating with a thickness of 0.8-1.2mm. The invention improves the fatigue performance of the welded structure by plasma spraying the low elastic modulus coating at the welding toe of the joint, and the plasma spraying coating at the welding toe of the joint can improve the shape change of the section, reduce the stress concentration there, and improve the fatigue of the welding structure Intensity; (2) compared with the welded test piece, the fatigue strength of the plasma sprayed test piece of the present invention improves by 25.9%, and the flame sprayed test piece only improves by 9.7%.
Description
Technical field
The present invention relates to a kind of post-treating method of Metal Material Welding joint, particularly a kind of plasma spraying method that improves fatigue performance of welded structure.
Background technology
The ability that welding joint bears static load generally is not less than mother metal, but the ability and the mother metal that bear repeated load greatly differ from each other, and therefore, causes some welded construction joint areas to cause fatigue cracking prematurely and loses efficacy.The major cause that welded construction fatigue strength is on the low side has: weld metal causes the abrupt change of cross-section; Unrelieved stress and distortion that local heating and inhomogeneous cooling cause; The welding flaw of toe zone such as undercut and slag inclusion etc.For concrete welded construction, can take some technological measures at postwelding, to improve its fatigue strength, weld remelting, local heating and low transformation temperature welding rod and ultrasonic impact processing etc. as welding toe detail sanding, shot-peening, TIG, its objective is and reduce stress concentration, eliminate otch or introduce compressive residual stress on the member top layer, but effect is not very good.
Whitman in 1970 and Webber have proposed a kind of method of improving fatigue performance of welded structure, promptly at weld seam welding toe deposition low elastic modulus thin layer.The test-results of Chedwick shows that the toe of weld thin layer can make the fatigue strength of welding joint obviously improve.
Summary of the invention
Technical problem to be solved of the present invention is, a kind of plasma spraying method that improves fatigue performance of welded structure is provided, and this method can reduce the stress concentration at welding joint place, improves welded fatigue strength.
The present invention is by improving welded fatigue property in the method for welding toe of joint plasma spraying low elastic modulus coating, and the welding toe of joint plasma sprayed coating can improve cross-sectional shape and change, and reduces the stress concentration at this place, improves welded fatigue strength.
For solving the problems of the technologies described above, the plasma spraying method that improves fatigue performance of welded structure of the present invention adopts plasma spray coating process at the weld face spray-on coating, and the preparation method of this spray-on coating may further comprise the steps:
A. the sample commissure being carried out blast handles;
B. at weld face plasma spraying bond coating, described primer is selected from Ni/Al, Ni/Cr or MCrAlY, and M is transition-metal Fe, Ni, Co or NiCo, and underlayer thickness is 0.03-0.07;
C. the powdered alloy plasma spray is coated in weld face and forms top coat, coat-thickness is 0.8-1.2mm.
Coat-thickness among the described step c is 0.9mm.Powdered alloy among the described step c can be Al contained Ni end and low-carbon (LC) comminuted steel shot.Powdered alloy among the described step c can also be powder of self-adhesive, composite powder or pure metal powder.
Compared with prior art, the present invention has following beneficial effect: (one) the present invention is by improving welded fatigue property in the method for welding toe of joint plasma spraying low elastic modulus coating, the welding toe of joint plasma sprayed coating can improve cross-sectional shape and change, reduce the stress concentration at this place, improve welded fatigue strength; (2) compare with as welded sample, the fatigue strength of plasma spraying test specimen of the present invention improves 25.9%, and the flame plating test specimen only improves 9.7%; (3) be 1.58～9.62 times of as welded sample the fatigue lifetime of plasma spraying test specimen of the present invention, and be as-welded 1.55～1.97 times the fatigue lifetime of flame plating test specimen; (4) plasma spraying processing of the present invention is better than flame plating to the effect of improving of fatigue performance of welded structure; (5) plasma spraying method of the present invention is the effective ways that improve fatigue performance of welded structure, and the 1Cr18Ni9Ti joint fatigue property behind the plasma spraying obviously improves; (6) finite element analysis shows that the theoretical stress concentration factor of as-welded sample welding toe is 2.75, and the stress concentration factor of spraying back welding toe significantly reduces.
Description of drawings
Fig. 1 is non-bearing cruciform joint figure;
Fig. 2 is for calculating the coating pattern simulation sprayed coating figure that adopts;
Fig. 3 is welding toe joint size of mesh opening figure;
Fig. 4 is the fracture position of fatigue sample;
Fig. 5 is as-welded and the match S-N curve spray treatment test specimen
Fig. 6 is toe zone σ
xDistribution plan;
Fig. 7 is coating and the σ of basal body interface place
yDistribution plan;
Fig. 8 is the stress distribution (σ of coating part after peeling off
x) figure;
Fig. 9 is that Young's modulus is to welding toe stress influence figure;
Figure 10 is that coat-thickness is to the welding toe stress influence;
Figure 11 is longitudinal angle welding line joint figure;
Figure 12 is a longitudinal angle welding line joint S-N curve.
Embodiment
Below in conjunction with embodiment the present invention is elaborated.
The welding of non-bearing cruciform joint:
As shown in Figure 1, sample material is a 1Cr18Ni9Ti sheet material, thickness 8mm.The mechanical property of sheet material sees Table 1.Fatigue sample adopts manual argon arc welding, square groove.Before the weldering steel plate is cut into 190 * 70 and 70 * 25 lath.In order to prevent and to reduce Welding Angular Deformation, position weldering in the side earlier, after the alignment by hand argon arc welding intersect welding four road weld seams.During welding from the end starting the arc of sample to the other end blow-out, guarantee to mill and can remove the starting the arc and blow-out district in the course of processing at postwelding.Leg 4～5mm, welding current 148A, weldingvoltage 18V, welding wire are 00Cr18Ni9.After finishing, sample welding mills processing experiment section size again.Arc transition place with specimen test section and gripping section polishes smooth at last, prevents from this fracture.
The mechanical property of table 1 1Cr18Ni9Ti
| Tensile strength sigma b/MPa | Yield strength σ 0.2/M pa | Elongation δ/% | Relative reduction in area ψ/% |
| 592 | 291 | 55 | 80 |
The welding process embodiment one of steel of the present invention or aluminium:
The welding process of steel of the present invention or aluminium adopts prior art.The plasma spraying method that improves fatigue performance of welded structure of the present invention adopts plasma spray coating process at the weld face spray-on coating, and this spray-on coating may further comprise the steps: before a. spraying blast is carried out in the sample commissure and handle.B. at weld face plasma spraying bond coating, described primer is selected from Ni/AL, Ni/Cr or McrALY, and M is transition-metal Fe, Ni, Co or NiCo, and underlayer thickness is 0.03～0.07mm; Preferably adopt nickel alclad bottom, prime coat thickness is preferably 0.05mm.C. the powder plasma spray is coated in weld face and forms top coat, coat-thickness is 0.8～1.2mm; The plasma spraying powder preferably adopts nickel alclad and low-carbon (LC) comminuted steel shot.Adopt the outer powder feeding of rifle during plasma spraying low-carbon (LC) comminuted steel shot, working gas is Ar+H
2, powder feeding gas is an argon gas, spray voltage 85V, and spraying current 480A, coat-thickness is preferably 0.9mm.In order to contrast, to get one group of sample and carry out flame plating.
The welding process embodiment two of steel of the present invention or aluminium:
Only be with the difference of embodiment one, adopt powder of self-adhesive as the plasma spraying powder.
The welding process embodiment three of steel of the present invention or aluminium:
Only be with the difference of embodiment one, adopt composite powder as the plasma spraying powder.
The welding process embodiment four of steel of the present invention or aluminium:
Only be with the difference of embodiment one, adopt alloy powder as the plasma spraying powder.
The welding process embodiment five of steel of the present invention or aluminium:
Only be with the difference of embodiment one, adopt the pure metal powder as the plasma spraying powder.
Fatigue test method:
Test is carried out on the 100KN HF fatigue testing machine, and the static load precision full range of trier is ± 0.2%, and dynamic load amplitude fluctuation degree full range is ± 2%.
The applied load situation is: all fatigue tests are all carried out under constant amplitude loading, and load type is a tension load, stress ratio R=0.
Stress calculation:
Get non-bearing fillet weld in the horizontal position sample during calculating, the toe of weld angle of weld seam is 45 degree, and square groove, leg are of a size of 0.6B (B is a specimen thickness).The Young's modulus of sprayed coating is E
c, the Young's modulus of weld seam is identical with test plate (panel), is E
p, get E
p=198GPa.Measure the Young's modulus of coating with the three point bending test of composite beam, the Young's modulus of flame spray coating and plasma sprayed coating is respectively 97.7GPa and 118.1GPa.Plate is the elastic linear state of strain, and the Poisson's ratio of mother metal, weld seam and coating is 0.3.
Spray treatment test specimen welding toe is coated with course mother metal rounding off, adopts coating pattern simulation sprayed coating as shown in Figure 2, applies tensile stress 180MPa at as shown in the figure directions X.Adopt the two dimensional plane strain model during calculating,, get it and 1/2 calculate because cruciform joint has symmetry.The grid of coating and former weld seam welding toe is divided as shown in Figure 3, and unit therefor is eight node isoparametric elements, and identical cell size 0.0125B is all adopted in coating and commissure under the various states, i.e. 0.1mm is 2mm away from the cell size of commissure.
In order to define stress concentration factor, the stress that is arranged in the plate surface cell in toe of weld zone behind the stress application is plotted in figure, and think the stress of drawing in the center of triangular element, if no special instructions, the toe of weld of mentioning herein is the toe of weld of the preceding former weld seam of spraying.By curve extrapolation to welding toe has been obtained effective stress concentration factor.It is emphasized that, stress concentration factor herein is not the real stress concentration factor of welding toe, (or other sharp-pointed discontinuous places) theoretic stress concentration factor is infinitely-great in the minor radius nook, and its value depends on the radius size of nook.The cell size of nook is more little in finite element model, and the stress value that calculates is also just big more, and this explanation has only that calculation result just can compare mutually when using identical cell size.
Fatigue test results:
The fatigue test results of various terminal sees Table 2～4.
As-welded and non-bearing cruciform joint sample flame plating all breaks at the toe of weld position, sees Fig. 4 a, b, and the plasma spraying sample breaks on mother metal, sees Fig. 4 c.Fracture surface of sample after the repeated stress failure as can be seen, the part has taken place flame plating sample welding toe coating peels off, plasma spraying does not then have the part to peel off phenomenon.Plasma spraying sample fatigue cracking is in the arc transition place crack initiation of test section and gripping section, illustrates that the fatigue property of plasma spraying test specimen improves comparatively obvious.
According to the test-results of table 2～4 and the routine test method of pressing fatigue strength, providing spray treatment front and back sample is 2 * 10 at the circulation cycle
6The time fatigue strength (survival rate is 50%), the results are shown in table 5.Contrast spray treatment test specimen and original as welded sample are 2 * 10 at the circulation cycle
6The time fatigue strength, the flame plating test specimen is compared with original as welded sample, the improvement degree of its fatigue strength reaches 9.7%; The plasma spraying test specimen is compared with original as welded sample, and its fatigue strength improves 25.9% approximately.
Draw match S-N curve as-welded and the spray treatment test specimen by the fatigue data of table 2～4, as shown in Figure 5, the data representation of band arrow breaks in mother metal or not fracture among the figure.Corresponding S-N curve in the comparison diagram, as can be seen: be lower than the test specimen through flame plating the fatigue lifetime of undressed as welded sample under identical stress level, the test specimen of flame plating is lower than the test specimen through plasma spraying; Under identical fatigue lifetime, the fatigue strength of plasma spray processing test specimen is higher than the test specimen of flame plating, and the fatigue strength of flame plating test specimen is higher than as welded sample.
The fatigue test results of the as-welded sample of table 2
| Specimen coding | Fatigue lifetime (* 10 6) | Fracture position | Stress range Δ σ (MPa) |
| 1 2 3 4 5 6 7 8 9 10 11 | 5 1.637 2.5 1.064 1.814 1.256 0.925 0.574 0.455 0.265 0.162 | Not disconnected toe of weld toe of weld toe of weld toe of weld toe of weld toe of weld toe of weld toe of weld toe of weld toe of | 160 170 170 180 180 180 200 200 220 220 240 |
The fatigue test results of table 3 flame plating sample
| Specimen coding | Fatigue lifetime (* 10 6) | Fracture position | Stress range Δ σ (MPa) |
| 1 2 3 4 5 | 5.185 2.277 1.379 0.464 0.324 | Not disconnected toe of weld toe of weld toe of weld mother metal | 170 180 200 220 240 |
The fatigue test results of table 4 plasma spraying sample
| Specimen coding | Stress range Δ σ (MPa) | Fatigue lifetime (* 10 6) | |
| 1 2 3 4 5 6 7 | 200 205 210 220 230 240 240 | 6.5 6.5 1.924 0.901 0.565 0.522 0.468 | Not disconnected not disconnected mother metal mother metal mother metal mother metal mother metal |
Table 5 fatigue strength Δ σ/2 * 10
6
| The sample state | As-welded | Flame plating | Deng from spraying |
| Fatigue strength Δ σ/MPa (2 * 10 6) | 169.8 | 186.2 | 213.8 |
Testing data statistical study and stress calculation result:
The statistical treatment of 1 fatigue data
According to the relevant document of International Institude of Welding (IIW), adopt following statistical method that the corresponding fatigue experiment data of various welding joints are handled, the characteristics of this statistical processing methods are:
Meet under the prerequisite of lognormal distribution in the hypothesis fatigue test results, with have same slope m and corresponding respectively K doubly two nominal S-N curves of positive and negative standard deviation form a data dispersion train.The result of Chu Liing drops in this dispersion train testing data with certain probability under a certain degree of confidence like this.Wherein K is referred to as eigenwert for dropping on probability and the closely-related parameter of respective confidence in the dispersion train with the quantity of testing data.
The width of this dispersion train is corresponding with the dispersiveness (standard deviation) of processing testing data.It depends on the confidence level that statistical treatment is adopted, and reaches the size that testing data drops on the survival probability in the dispersion train, promptly is closely related with eigenwert K.
The specified survival probability of International Institude of Welding (IIW) is 95%, and degree of confidence is 75%.
Nominal value can calculate by following program:
1) calculates the stress range Δ σ or the maximum stress σ of all fatigue data points
MAX, cycle index N denary logarithm value.
2) adopt power function model regression Calculation exponent m and constant logC value:
mlogΔσ+logN＝logC (1)
3) establish X
iBe the logarithmic value of testing data, utilize the m value that is obtained, calculate the mean value X of logC
mWith standard deviation stdv:
4) computation of characteristic values X
k:
X
k＝X
m-K·stdv (4)
The X that obtains by above-mentioned formula
mAnd X
kCalculate corresponding C respectively
mAnd C
k
Handle fatigue data in this test by above-mentioned statistical method, statistics sees Table 6.
In order to obtain changing conditions fatigue lifetime of spray treatment front and back test specimen under the identical stress level, the fatigue test results in the table is pressed equation S respectively
mN=C match (parameter of S-N curve sees Table 6), obtaining the plasma spraying fatigue Life is 1 * 10
7The time pairing stress range under fatigue lifetime of as welded sample, flame plating test specimen, and as welded sample fatigue lifetime be 1 * 10
5The time pairing stress range under fatigue lifetime of plasma spraying test specimen, flame plating test specimen, the results are shown in Table 7.
The statistics of table 6 fatigue data
| The sample state | m | C m | C k | stdv |
| As-welded flame plating plasma spraying | 7.08 7.81 12.54 | 0.139×10 23 0.114×10 25 0.314×10 36 | 0.113×10 23 0.838×10 24 0.164×10 36 | 0.033 0.038 0.080 |
The contrast of table 7 fatigue property
| The sample state | Stress range Δ σ 1/MPa | Life-span N 1(× 10 5) | Stress range Δ σ 2/MPa | Life-span N 2(× 10 7) |
| As-welded flame plating plasma spraying | 259 259 259 | 1.0 1.547 1.582 | 186 186 186 | 0.104 0.205 1.0 |
The fatigue lifetime of test specimen under the various states in the contrast table 7, be 1.58～9.62 times of as welded sample the fatigue lifetime of plasma spraying test specimen, be as-welded 1.55～1.97 times the fatigue lifetime of flame plating test specimen, and what the plasma spraying test specimen was described improves effect apparently higher than the flame plating test specimen.
2 stress calculation interpretations of result
Fig. 6 be the X of as-welded, flame plating and plasma spraying sample toe zone to stress (hereinafter referred to as σ
x) distribute.The theoretical stress concentration factor of as-welded sample welding toe is 2.75.Flame plating and plasma spraying sample maximum value all occurs at toe of weld and coating welding toe stress.The stress concentration factor of flame plating test specimen toe of weld and coating welding toe is respectively 1.2 and 1.1, and the stress concentration factor of plasma spraying test specimen toe of weld and coating welding toe is respectively 1.05 and 1.13, and stress concentration factor all significantly reduces.
Spraying sample toe zone coating and the Y of basal body interface place to stress (hereinafter referred to as σ
y) distribute and see Fig. 7.Flame plating and plasma spraying sample welding toe σ
yMaximum value appears, with the distance toe of weld apart from increase, σ
yReduce gradually.The interface bond strength of coating and matrix, the interface bond strength of sprayed coating and the σ of welding toe have been tested with the bonding stretching method
ySee Table 8.Flame spray coating toe zone coating and the σ of basal body interface place
yGreater than its interface bond strength, coating the part will occur and peel off phenomenon when fatigue loads.Plasma spraying sample toe zone coating and the σ of basal body interface place
yInterface bond strength less than coating.
The σ in toe of weld zone, back is peeled off in flame plating sample welding toe coating part
xFig. 6 is seen in distribution, and the welding toe stress concentration factor is 2.56, approaches 2.75 of as-welded sample.Fig. 8 is the stress (σ after peel off welding toe coating part
x), coating is obviously separated with matrix behind the applied load, does not produce the stress shunting action substantially, this just flame plating test specimen fatigue strength be lower than the reason of plasma spraying test specimen.From the post-rift fracture of fatigue sample, peel off coating part, flame plating sample toe zone, and the plasma spraying sample does not then have the phenomenon of peeling off, and the exactness of The results has been described.
Fig. 9 was seen in the influence of coating Young's modulus counter stress when coat-thickness was 1.2mm.Increase the σ of coating welding toe with the coating Young's modulus
xRaise the σ of former weld seam welding toe gradually
x, σ
yReduce.σ wherein
yChange obviously, be lower than Bond Strength of Coating by becoming of beginning greater than coating and substrate combinating strength.
When the coating Young's modulus was the Young's modulus 118.1GPa of plasma sprayed coating, Figure 10 was seen in the influence of coat-thickness counter stress.The σ of former weld seam welding toe
x, σ
yStress all reduces with the increase of coat-thickness, but the stress of coating welding toe increases gradually.
Table 8 sample welding toe σ
yAnd anchoring strength of coating
| The sample state | Welding toe σ y (MPa) | Anchoring strength of coating (MPa) |
| The flame plating plasma spraying | 33.3 26.6 | 24.2 45.6 |
By above experiment, can obtain to draw a conclusion:
(1) fatigue strength of as welded sample is 169.8MPa, and the flame plating test specimen is 186.2MPa, and the plasma spraying test specimen is 213.8MPa.Compare with as welded sample, the fatigue strength of plasma spraying test specimen improves 25.9%, and the flame plating test specimen only improves 9.7%.
(2) be 1.58～9.62 times of as welded sample the fatigue lifetime of plasma spraying test specimen, and be as-welded 1.55～1.97 times the fatigue lifetime of flame plating test specimen.
(3) plasma spraying is better than flame plating to the effect of improving of fatigue performance of welded structure.
(4) plasma spraying is the effective ways that improve fatigue performance of welded structure, and the 1Cr18Ni9Ti joint fatigue property behind the plasma spraying obviously improves.
(5) finite element analysis shows that the theoretical stress concentration factor of as-welded sample welding toe is 2.75, and the stress concentration factor of spraying back welding toe significantly reduces.The σ of welding toe
x, σ
yIncrease with coat-thickness, Young's modulus reduces.
(6) near the σ flame plating sample toe of weld
yGreater than the stretching bonding strength of coating, cause welding toe coating part to be peeled off, this is that flame plating improves the reason that the fatigue property effect is lower than the plasma spraying sample.
Figure 11 is longitudinal angle welding line joint figure.The longitudinal angle welding line joint adopts covered arc welding, earlier steel plate is cut into the lath of 190 * 70 (making mainboard) and 60 * 25 (making gusset joint plate), and preceding mainboard is milled of weldering is processed into 190 * 60mm and processing experiment section size 40mm, 110mm and R25.In order to prevent and angular distortion when reducing to weld, position weldering in both sides, gusset joint plate middle part earlier, electric-arc welding is intersected in the mainboard both sides and is welded by hand then.During welding earlier in the gusset joint plate one middle side part starting the arc, behind the Rotate 180 degree of gusset joint plate end in the middle part blow-out of gusset joint plate opposite side.Welding condition sees Table 9.The test-results of longitudinal angle welding line joint sees Table 10.Longitudinal angle welding line joint fatigue property sees Table 11.Longitudinal angle welding line joint S-N curve is seen Figure 12.
The welding condition of table 9 longitudinal angle welding line joint
| Welding rod | Electrode diameter (mm) | Welding current (A) | Weldingvoltage (V) | Welding speed (S/mm.min -1) |
| A107 | Φ2.5 | 100 | 22～24 | 100 |
The test-results of table 10 longitudinal angle welding line joint
| The sample state | Stress range Δ σ (MPa) | Fatigue lifetime (* 10 6) | Fracture position |
| As-welded | 120 | 5 | Not disconnected |
| 130 | 1.88 | Toe of | |
| 140 | 1.25 | Toe of | |
| 150 | 0.966 | Toe of | |
| 160 | 0.744 | Toe of weld | |
| 170 | 0.566 | Toe of | |
| 180 | 0.465 | Toe of | |
| 200 | 0.317 | Toe of weld | |
| Plasma spraying | 150 | 6.5 | Not disconnected |
| 160 | 2.43 | Toe of weld | |
| 170 | 1.75 | Toe of | |
| 180 | 1.37 | Toe of | |
| 200 | 0.525 | Toe of | |
| 220 | 0.312 | Toe of | |
| 240 | 0.114 | Toe of weld |
Table 11 longitudinal angle welding line joint fatigue property
| The sample state | Fitting constant | Fatigue property | ||||
| m | C | Fatigue strength Δ σ/MPa (2 * 10 6) | Fatigue lifetime N * 10 6/cycles | |||
| 195MPa | 170MPa | 155MPa | ||||
| As-welded | 4.80 | 3.02×10 16 | 131.8 | 0.309 | 0.589 | 1.084 |
| Plasma spraying | 7.85 | 6.03×10 23 | 169.8 | 0.631 | 1.866 | 5.012 |
| The improvement degree | - | - | 28.9％ | 2.0 doubly | 3.2 doubly | 4.6 doubly |
Claims (2)
1. a plasma spraying method that improves fatigue performance of welded structure is characterized in that, adopts plasma spray coating process at the weld face spray-on coating, and the preparation method of this spray-on coating may further comprise the steps:
A. the sample commissure being carried out blast handles;
B. at weld face plasma spraying bond coating, described primer is selected from Ni/Al, Ni/Cr or MCrAlY, and M is transition-metal Fe, Ni, Co or NiCo, and underlayer thickness is 0.03-0.07mm;
C. Al contained Ni end or soft steel powder plasma are sprayed on weld face formation top coat, coat-thickness is 0.8-1.2mm.
2. a kind of plasma spraying method that improves fatigue performance of welded structure according to claim 1 is characterized in that the coat-thickness among the described step c is 0.9mm.
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| JP5543261B2 (en) * | 2010-04-14 | 2014-07-09 | 株式会社Ｉｈｉ | Ultrasonic peening construction method |
| CN102861990B (en) * | 2012-10-17 | 2014-11-05 | 山东电力集团公司电力科学研究院 | Method for improving fusion depth in laser welding process of aluminum alloy |
| CN106676455B (en) * | 2015-11-04 | 2019-08-02 | 中国人民解放军装甲兵工程学院 | The method of raising contact fatigue property is combined in a kind of texturing with coating process optimization |
| CN106676459A (en) * | 2015-11-04 | 2017-05-17 | 中国人民解放军装甲兵工程学院 | Method for improving anti-fatigue performance of coating |
| CN106676456B (en) * | 2015-11-04 | 2019-08-02 | 中国人民解放军装甲兵工程学院 | A method of control coat inside structure improves coating anti-fatigue performance |
| CN107460431A (en) * | 2017-10-12 | 2017-12-12 | 河北工业大学 | A kind of method for improving 6061 aluminum alloy surface plasma spraying Ni60A anchoring strength of coating |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58179653A (en) * | 1982-04-15 | 1983-10-20 | Canon Inc | Recording system |
| EP0824986A1 (en) * | 1996-08-22 | 1998-02-25 | Castolin S.A. | Manufacturing method of corrosion resistance connecting pipes |
| CN1210048A (en) * | 1997-09-04 | 1999-03-10 | 国营五二三厂 | Argon arc welding spot welding method for cadmium plate with thickness of 0.5 mm |
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2005
- 2005-04-07 CN CNB2005100132849A patent/CN1324160C/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58179653A (en) * | 1982-04-15 | 1983-10-20 | Canon Inc | Recording system |
| EP0824986A1 (en) * | 1996-08-22 | 1998-02-25 | Castolin S.A. | Manufacturing method of corrosion resistance connecting pipes |
| CN1210048A (en) * | 1997-09-04 | 1999-03-10 | 国营五二三厂 | Argon arc welding spot welding method for cadmium plate with thickness of 0.5 mm |
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