Laser repairing process without the vehicle mould of preheating
The application divides an application, the application number of original application: 201210248963.4, the applying date: 2012-07-18, the laser repairing process > > of invention and created name < < vehicle mould.
Technical field
The present invention relates to a kind of laser cladding method, especially a kind of laser melting coating restorative procedure of die surface.
Background technology
Vehicle mould is the general name of the mould of punching body of a motor car stamping parts, such as: top cover Abkantwerkzeug, crossbeam stiffening plate pressure-shaped mould etc., vehicle mould is being brought into play very important effect in car industry.In recent years, along with the develop rapidly of domestic automobile process industry, the development of the Die Manufacturing Enterprise of China is very rapid, has made significant headway, but manufacture advanced level with Foreign Automobile mould, compares, and still has obvious gap.Because the requirement that vehicle mould is manufactured in technical requirements and quality product is more and more higher, under the strong competition of the stricter foreign capital affiliate of technical requirements, the pressure that domestic vehicle mould production faces also grows with each passing day.At present, mould and die accuracy is poor, the life-span is short, construction cycle length is the mortal wound of domestic automobile mould.There is the situation of wrong processing in domestic automobile mould, in use can produce wearing and tearing in various degree in making processes, the condemnation factor of mould, up to 30%, has caused huge waste, causes domestic automobile mould competitive power on market not enough.Quality is exactly the life of enterprise, and the quality of mould is directly connected to the counterweight of competition among enterprises.For this situation, current most enterprises adopts common built-up welding to process vehicle mould is repaired, but because moulding stock is mostly high-carbon alloy steel or cast steel, common built-up welding meeting brings the shortcomings such as deflection is large, hardness is not enough, easy to crack to mould, have a strong impact on the service precision of mould, cause produced quality product to decline.
Laser melting coating refers to that with different adding material modes, place selecteed coated material on by cladding matrix surface makes it to melt with matrix surface skim through laser irradiation simultaneously, and it is extremely low after rapid solidification, to form extent of dilution, become the top coat of metallurgical binding with matrix, significantly improve the processing method of wear-resisting, anti-corrosion, heat-resisting, the anti-oxidant and electrical specification of substrate surface, thereby reach the object of surface modification or reparation.With built-up welding, spraying, plating and gas phase sediment-filled phase ratio, laser melting coating has that extent of dilution is little, dense structure, coating and matrix is combined, be applicable to that cladding material is many, granularity and the feature such as content is large.How laser melting and coating technique being effectively applied to vehicle mould reparation, is the problem that those skilled in the art need to solve.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind ofly carries out laser melting coating to die surface, makes the size of its surface hardness and abrading section reach the laser repairing process of the vehicle mould of service requirements.
In order to solve the problems of the technologies described above, the invention provides a kind of laser repairing process of vehicle mould, it is characterized in that, comprise the following steps:
A. die surface is processed, mould is detected to analysis;
B. mould is carried out to low-temperature heat, remove steam and the oil gas on die matrix surface;
C. according to the detection analytical results of mould, die cavity to die wear position is programmed, formulate processing parameter, successively laser melting coating is carried out in the plane position on the edge of mould, mould and the stepped portions on mould, in laser cladding process, mould is carried out to oscillating aging processing;
D. detect.
In order to make cladding layer there is higher hardness and wear resistance, and welding property is better, a kind of preferred technical scheme is: the component of the powdered alloy adopting in above-mentioned steps C and weight percent content are C≤0.1%, Cr:10% to 13%, B:1.5% to 2.5%, Si:1% to 2%, Mo:0.5% to 1.2%, Mn:8% to 12%, W:6% to 12%, TiO
2: 5% to 15%, all the other are Fe.The powdered alloy that this laser repairing process adopts has strictly been controlled the content of C, makes it be not more than 0.1%, is conducive to improve the wettability of cladding layer, prevents from cladding process, cracking and pore; Simultaneously in powdered alloy, by adding appropriate B, Si, alloy to be formed after solidifying take austenite be the matrix of leading, and utilizes appropriate Cr, Mo element to carry out basic alloy strengthening to ferrous alloy, also added in addition appropriate Mn, W, TiO
2ferrous alloy is carried out to further alloy strengthening, even if C content is lower, more than the hardness of cladding layer also can reach 55HRC, has fully met the hardness requirement that mould is used, and there is very high wear resistance.
In order to guarantee the performance of cladding layer, better eliminate built-up welding stress, a kind of preferred technical scheme is: in above-mentioned steps C, adopt the mode of preset powder feeding, the fast-transverse-flow CO2 laser of take carries out lap connection scanning to mould as light source; Laser power is 1500W to 1900W, and absolute altitude is 260mm to 275mm, and spot size is 10mm * 1.8mm, and sweep velocity is 110mm/min to 140mm/min, and amount of lap is 6.5mm, and powder sending quantity is 12g/min to 18g/min.This laser repairing process adopts broad band laser bundle, and efficiency is higher; Adopt the mode of preset powder feeding, strict control powder sending quantity, and laser power, sweep velocity, amount of lap etc. are optimized, make die deformation amount little, the fusion rate of the matrix at cladding layer and die wear position is high, in conjunction with closely, the homogeneity of structure of cladding layer is good, thickness and hardness even.
In order better to remove steam and the oil gas of vehicle mould matrix surface, a kind of preferred technical scheme is: the Heating temperature in above-mentioned steps B is 80 ℃ to 150 ℃.
For vehicle mould to be repaired is repaired successfully in the process of laser melting coating, and obtain better repairing effect, a kind of preferred technical scheme is: above-mentioned steps A removes the dust on mould, greasy dirt, corrosion; Record the original working conditions of mould, hardness and mechanical property parameters; Detect the size at each position of mould, determine abrading section and abrasion loss thereof; Remove the right angle of abrading section, remove the fatigue layer of abrading section, and clean.
In order to guarantee the quality of the vehicle mould after reparation, a kind of preferred technical scheme is: above-mentioned steps D detects die surface hardness; Detect die deformation amount; Die surface is carried out to mechanical workout; Carry out permeation flaw detection, verification.
Technique scheme of the present invention has the following advantages compared to existing technology: in the laser repairing process of vehicle mould of the present invention, before mould laser melting coating He in laser cladding process, do not need integral body or local heating.This technique only need to be carried out low-temperature heat in order to remove steam and the oil gas on die matrix surface before laser melting coating; Then, by first corner, back plane, then the laser melting coating at step right angle sequentially avoids heat to concentrate generation thermal stresses; In laser cladding process, the stress while welding by vibration aging on eliminating.This technique can not affect the mechanical property of mould without preheating and annealing, can not make mould produce distortion, is conducive to further improve hardness and the wear resistance of mould.
Embodiment
(embodiment 1)
The concrete steps of the laser repairing process of the vehicle mould of the present embodiment are as follows:
A. die surface to be repaired is processed, mould is detected to analysis.
By removings such as upper dust, greasy dirt, corrosions; Record the original working conditions of mould, hardness and mechanical property parameters; Detect the size at each position of mould, determine abrading section and abrasion loss thereof; By polishing, remove the right angle of abrading section, remove the fatigue layer of abrading section, and clean.
B. mould is carried out to low-temperature heat, Heating temperature is 100 ℃, in order to remove steam and the oil gas on die matrix surface.
C. according to the detection analytical results of mould, die cavity to die wear position programme (numerical control machining simulation system that programming can be used Siemens Company), formulate processing parameter, first the edge of mould is carried out to laser melting coating, then laser melting coating is carried out in the plane position on mould, then the stepped portions on mould is carried out to laser melting coating.In laser cladding process, ceaselessly with copper rod, evenly knock mould alloy cladding layer, thereby make mould vibration eliminate welding stress.
Adopt the mode of preset powder feeding, the fast-transverse-flow CO2 laser of take carries out lap connection scanning to mould as light source.Laser power is 1700W, and absolute altitude (being that laser apparatus is from the distance between Substrate, absolute altitude=focal length+defocusing amount) is 270mm, and spot size is 10mm * 1.8mm, and sweep velocity is 120mm/min, and amount of lap is 6.5mm, and powder sending quantity is 15g/min.The component of the powdered alloy adopting and weight percent content are C:0.08%, Cr:11%, B:2%, Si:1.5%, Mo:1%, Mn:10%, W:8%, TiO
2: 10%, all the other are Fe.
D., after reparation finishes, detect.
Detect surface hardness; Detect deflection; According to the requirement of drawing, die surface is carried out to mechanical workout; Carry out permeation flaw detection, detect and whether have pore, slag inclusion, slight crack etc. to affect the defect of mould mechanical property; Carry out verification, whether quality inspection is qualified.
The hardness mean value on the vehicle mould surface after this technique reparation is 57.2HRC, and in all check points, the surface hardness of hardness value lowest part is 55.9HRC.
(embodiment 2)
The rest part of the laser repairing process of the vehicle mould of the present embodiment is identical with embodiment 1, and difference is:
The component of the powdered alloy adopting and weight percent content are C:0.08%, Cr:15%, B:1.5%, Si:1%, Mo:0.5%, Mn:8%, W:6%, TiO
2: 8%, all the other are Fe.
The hardness mean value on the vehicle mould surface after this technique reparation is 56.5HRC, and in all check points, the surface hardness of hardness value lowest part is 55.2HRC.
(embodiment 3)
The rest part of the laser repairing process of the vehicle mould of the present embodiment is identical with embodiment 1, and difference is:
The component of the powdered alloy adopting and weight percent content are C:0.1%, Cr:13%, B:2.5%, Si:2%, Mo:1.2%, Mn:12%, W:12%, TiO
2: 15%, all the other are Fe.
The hardness mean value on the vehicle mould surface after this technique reparation is 57.8HRC, and in all check points, the surface hardness of hardness value lowest part is 56.3HRC.
Obviously, above-described embodiment is only for example of the present invention is clearly described, and is not the restriction to embodiments of the present invention.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here exhaustive without also giving all embodiments.And these belong to apparent variation that spirit of the present invention extended out or change still among protection scope of the present invention.