Without the need to the laser repairing process of the vehicle mould of preheating
The application is divisional application, the application number of original application: 201210248963.4, the applying date: 2012-07-18, invention and created name " laser repairing process of 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 plays very important effect in car industry.In recent years, along with the develop rapidly of domestic automobile process industry, the Die Manufacturing Enterprise development of China is very rapid, has made significant headway, but compared with Foreign Automobile Making mold advanced level, still there is obvious gap.The requirement be manufactured in technical requirements and quality product due to vehicle mould is more and more higher, and 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 mistake processing in making processes in domestic automobile mould, in use can produce wearing and tearing in various degree, the condemnation factor of mould, up to 30%, causes huge waste, and commercially competitive power is not enough to cause domestic automobile mould.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 process to repair vehicle mould, but because moulding stock is mostly high-carbon alloy steel or cast steel, common built-up welding can bring the shortcomings such as deflection is large, hardness is not enough, easy to crack to mould, have a strong impact on mold use precision, cause produced quality product to decline.
Laser melting coating refers to and is made it to melt with matrix surface skim through laser irradiation by coated material cladding matrix surface placed by selecting with different adding material modes simultaneously, and it is extremely low to form extent of dilution after rapid solidification, the top coat of metallurgical binding is become with matrix, the remarkable processing method improving the wear-resisting, anti-corrosion, heat-resisting, anti-oxidant of substrate surface and electrical specification, thus 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 needs to solve.
Summary of the invention
The technical problem to be solved in the present invention is to provide one and 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, comprising the following steps:
A. die surface is processed, detection is carried out to mould and analyzes;
B. low-temperature heat is carried out to mould, remove steam and the oil gas on die matrix surface;
C. according to the detection analytical results of mould, the die cavity at die wear position is programmed, formulate processing parameter, successively laser melting coating is carried out to the plane position on the edge of mould, mould and the stepped portions on mould, in laser cladding process, vibration stress relief treatment is carried out to mould;
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 adopted 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 strictly controls the content of C, makes it be not more than 0.1%, is conducive to the wettability improving cladding layer, prevents from cracking in cladding process and pore; Simultaneously make alloy form matrix based on austenite after solidification by appropriate B, the Si of interpolation in powdered alloy, utilize appropriate Cr, Mo element to carry out basic alloy strengthening to ferrous alloy, also added appropriate Mn, W, TiO in addition
2carry out further alloy strengthening to ferrous alloy, even if C content is lower, the hardness of cladding layer also can reach more than 55HRC, fully meets the hardness requirement that mould uses, and has very high wear resistance.
In order to ensure the performance of cladding layer, better eliminate built-up welding stress, a kind of preferred technical scheme is: the mode adopting preset powder feeding in above-mentioned steps C is that light source carries out lap connection scanning to mould with fast-transverse-flow CO2 laser; 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, combine closely, the homogeneity of structure of cladding layer is good, thickness and hardness even.
In order to better 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 DEG C to 150 DEG C.
In order to make vehicle mould to be repaired repair successfully in the process of laser melting coating, and obtain better repairing effect, a kind of preferred technical scheme is: the dust on mould, greasy dirt, corrosion are removed by above-mentioned steps A; Working conditions, hardness and mechanical property parameters that record mould is original; 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 ensure the quality of the vehicle mould after repairing, a kind of preferred technical scheme is: above-mentioned steps D detects die surface hardness; Detect die deformation amount; Mechanical workout is carried out to die surface; Carry out permeation flaw detection, verification.
Technique scheme of the present invention has the following advantages compared to existing technology: before mould laser melting coating He in laser cladding process, do not need entirety or local heating in the laser repairing process of vehicle mould of the present invention.This technique only needs before laser melting coating, to carry out low-temperature heat in order to remove steam and the oil gas on die matrix surface; Then, by first corner, back plane, then the laser melting coating order at step right angle avoids heat to concentrate generation thermal stresses; In laser cladding process, stress when being welded by vibration aging on eliminating.This technique can not affect the mechanical property of mould without the need to preheating and annealing, mould can not be made to produce distortion, be conducive to the hardness and the wear resistance that improve mould further.
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, detection is carried out to mould and analyzes.
By removings such as upper dust, greasy dirt, corrosions; Working conditions, hardness and mechanical property parameters that record mould is original; Detect the size at each position of mould, determine abrading section and abrasion loss thereof; Removed the right angle of abrading section by polishing, remove the fatigue layer of abrading section, and clean.
B. carry out low-temperature heat to mould, Heating temperature is 100 DEG C, in order to remove steam and the oil gas on die matrix surface.
C. according to the detection analytical results of mould, (numerical control machining simulation system that programming can use Siemens Company) is programmed to the die cavity at die wear position, formulate processing parameter, first laser melting coating is carried out to the edge of mould, then laser melting coating is carried out to the plane position on mould, then laser melting coating is carried out to the stepped portions on mould.In laser cladding process, ceaselessly evenly knock mould alloy cladding layer with copper rod, make mold vibration thus eliminate welding stress.
Adopting the mode of preset powder feeding, is that light source carries out lap connection scanning to mould with fast-transverse-flow CO2 laser.Laser power is 1700W, and absolute altitude (namely 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 adopted 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. repair after terminating, detect.
Detect surface hardness; Detect deflection; According to the requirement of drawing, mechanical workout is carried out to die surface; Carry out permeation flaw detection, detect and whether have pore, slag inclusion, slight crack etc. to affect the defect of mould machine performance; Verify, 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 adopted 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 adopted 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 the need to also giving all embodiments.And these belong to spirit institute's apparent change of extending out of the present invention or change and are still among protection scope of the present invention.