CN110360948A - A kind of laser cladding layer and Pool characterizing method - Google Patents

Abstract

The invention relates to a laser cladding layer and molten pool morphology characterization method, which belongs to the technical field of laser cladding remanufacturing, and relates to a laser cladding layer and molten pool morphology characterization method. In this method, a wire cutting machine is used to cut the clad substrate sample along the direction perpendicular to the scanning path of the cladding layer; First, grind according to the order of particle size from small to large; then take the polished matrix sample for super depth of field photography; then use arcs with different curvature radii to draw the contours of the cladding layer and molten pool in the super depth of field photo , and record the radius of curvature of each arc; finally measure the width, height and angle between the cladding layer and the molten pool of the entire profile. This method can quickly and accurately characterize the cladding layer and molten pool morphology.

Description

A laser cladding layer and molten pool morphology characterization method

technical field

The invention belongs to the technical field of laser cladding and remanufacturing, and relates to a laser cladding layer and a method for characterizing the morphology of a molten pool.

Background technique

Laser cladding technology is an advanced remanufacturing technology. Due to its many advantages such as small heat-affected zone, small workpiece deformation and high bonding strength, it is widely used in the field of rapid prototyping and repair of parts. However, in the process of rapid prototyping and repairing of parts, the process parameters of laser cladding have a crucial influence on the quality of forming and repairing, and the geometry of the cladding layer has a great influence on the lap rate and Z-axis of laser cladding. Process parameters such as lifting amount have a direct impact, so the characterization of laser cladding layer and molten pool morphology plays a vital role in the rapid prototyping and repair quality of parts. Aiming at the characterization of the geometric morphology of the laser cladding layer, Dai Xiaoqin et al.’s patent “A Method for Automatically Controlling the Geometric Morphology of Laser-Induction Composite Cladding Coating” (CN103060798 U) provides a method of using cladding coating width and thickness A method for characterizing the geometry of cladding coatings. Aiming at the characterization of the geometric shape of the laser molten pool, Sun Jun et al.'s patent "a method for measuring the shape of the electroslag remelted metal molten pool" (CN105675513 A) provides a method to characterize the geometry of the molten pool by the depth of the metal molten pool. method of appearance. However, neither of these two methods can fully characterize the morphology of the cladding layer and the molten pool, especially when performing laser cladding on an inclined base surface, due to the influence of gravity on the tension of the cladding layer and molten pool, the cladding The contours of the cladding layer and the molten pool are no longer symmetrical, so the original characterization method of the cladding layer and the molten pool cannot express the influence of gravity on the cladding layer and the molten pool, and it is impossible to study the effect of gravity on the zero Rapid prototyping of components and impact on repair quality. Therefore, in order to fully characterize the morphology of the cladding layer and the molten pool, so as to achieve the purpose of rapid prototyping and repair quality research on the inclined base surface due to gravity, it is necessary to invent a laser cladding layer and molten pool morphology Characterization method.

Contents of the invention

The present invention overcomes the defects of the prior art, especially when performing laser cladding on an inclined base surface, due to the influence of gravity on the tension of the cladding layer and the molten pool, the contours of the cladding layer and the molten pool are no longer Therefore, the existing characterization methods for the cladding layer and molten pool morphology cannot express the influence of gravity on the cladding layer and molten pool morphology, and thus cannot study the influence of gravity on the rapid prototyping and repair quality of parts; especially It is aimed at the characterization of the cladding layer and molten pool morphology on the surface of the inclined substrate. A laser cladding layer and molten pool morphology characterization method was invented. In this method, a wire cutting machine is used to cut the cladding substrate sample. Then, the cut matrix sample was polished on sandpaper of different particle sizes according to the method of metallographic sample preparation; and then the polished matrix sample was photographed with super depth of field. Then use arcs with different radii of curvature to draw the contours of the cladding layer and molten pool in the ultra-depth-of-field photos; finally measure the width and height of the entire contour and the angle between the cladding layer and the molten pool. In this way, the purpose of fully characterizing the cladding layer and the shape profile of the molten pool can be achieved, and the purpose of studying the influence of gravity on the rapid prototyping and repair quality of the inclined base can be realized.

The technical solution adopted in the present invention is a laser cladding layer and molten pool morphology characterization method, which is characterized in that the method first uses a wire cutting machine to cut the clad substrate sample along the direction perpendicular to the scanning path of the cladding layer Cut it; then grind the cut matrix sample on sandpaper of different particle sizes according to the method of metallographic sample preparation, and polish it in the order of particle size from small to large; then take the polished matrix sample for ultra-depth-of-field photography ; Then use arcs with different curvature radii to draw the contours of the cladding layer and molten pool in the ultra-depth-of-field photo, and record the radius of curvature of each arc; finally measure the width, height and cladding layer of the entire contour and the angle between the molten pool. The specific steps of the method are as follows:

Step 1 Cut the substrate sample that has been clad

Use a wire cutting machine to cut the clad substrate sample along the direction perpendicular to the scanning path of the cladding layer;

Step 2 Grinding the cut matrix sample

According to the metallographic sample preparation method, the cut matrix samples are polished on sandpaper of different particle sizes in order of particle size numbers from small to large;

Step 3 Take photos with super depth of field

Use the ultra-depth-of-field instrument to take pictures of the polished substrate samples;

Step 4: Expand and draw the contours of the cladding layer and molten pool

Utilize arcs with different radii of curvature to draw the contours of cladding layers and molten pools in ultra-depth-of-field photos, and record the radii of curvature of each arc;

Step 5 Measure the morphology and profile of the cladding layer and molten pool

Measure the width, height and angle between the cladding layer and the molten pool of the entire topographical outline drawn by the ultra-depth-of-field photo extension.

The beneficial effect of the invention is to provide a characterization method for the cladding layer on the surface of the inclined substrate and the profile of the molten pool. The cladding layer on the surface of the inclined substrate and the profile of the molten pool are characterized by the radius of curvature of different arcs, the width and height of the entire profile, and the angle between the cladding layer and the molten pool, which can not only fully characterize the cladding layer It can also achieve the purpose of studying the influence of gravity on the rapid prototyping and repair quality of inclined base surfaces. The method is simple and direct, and realizes rapid and accurate characterization of the cladding layer and molten pool morphology.

Description of drawings

Figure 1 is a schematic diagram of the position of the laser cladding inclined substrate, and Figure 2 is a schematic diagram of the position of the substrate to be cut,

Figure 3 is the ultra-depth-of-field photo of the matrix sample.

Fig. 4 is a schematic diagram of the arc numbering of the cladding layer and the contour of the molten pool. Among them, the cladding layer contour is enveloped by No. 1 arc, No. 2 arc, No. 3 arc and No. 4 arc, and the molten pool contour is surrounded by No. 5 arc, No. 6 arc, No. Arc No. 9, Arc No. 9, Arc No. 10 and Arc No. 11 are enveloped.

Figure 5 is a schematic diagram of the overall morphology of the cladding layer and molten pool. Among them, W-width, h-height, α-the left angle between the cladding layer and the molten pool, and β-the right angle between the cladding layer and the molten pool.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and technical solutions.

The base material used in this example is 17CrNiMo6, and the cladding layer material is Ni60. The inclination angle of the substrate is 60°, the laser power is 2000W, the scanning speed is 0.003m/s, and the powder feeding rate is 20r/min. The specific steps of the method are as follows:

Step 1 Cut the substrate sample that has been clad

Use a wire cutting machine to cut the clad substrate sample along the direction perpendicular to the scanning path of the cladding layer, that is, cut along the position marked with the cutting line in Figure 2;

Step 2 Grinding the cut matrix sample

Grind one of the cut matrix samples on sandpaper with a particle size of 80, 120, 400, 800, 1500, 2000 and 2500 according to the method for metallographic sample preparation, and then grind the polished matrix sample to polish;

Step 3 Take photos with super depth of field

Use the ultra-depth-of-field instrument to take pictures of the polished substrate sample, as shown in Figure 3;

Step 4: Expand and draw the contours of the cladding layer and molten pool

Utilize arcs with different curvature radii to draw the contours of the cladding layer and molten pool in the ultra-depth-of-field photo shown in Figure 3, and record the curvature radius of each arc. As shown in Figure 4, the cladding layer contour can be enveloped by four sections of the No. 1 arc, the No. 2 arc, the No. 3 arc and the No. 4 arc. The curvature radii of the No. 1 arc and the No. 4 arc The radius of curvature of the No. 2 arc is 27.8mm, the radius of curvature of the No. 2 arc is 13.9mm, and the radius of curvature of the No. 3 arc is 4.7mm; the contour of the molten pool can be composed of No. 5 arc, No. 6 arc, No. 7 arc, No. Arc, No. 10 arc and No. 11 arc are enveloped by seven sections, of which the radius of curvature of arc No. 5 is 0.4mm, the radius of curvature of arc No. 6 is 7.5mm, and the radius of curvature of arc No. 7 is 1.5mm. The radius of curvature of arc No. 8 is 5mm, the radius of curvature of arc No. 9 is 4.2mm, the radius of curvature of arc No. 10 is 0.4mm, and the radius of curvature of arc No. 11 is 5mm;

Step 5 Measure the morphology and profile of the cladding layer and molten pool

Measure the width, height and angle between the cladding layer and the molten pool of the entire topographical outline drawn by the ultra-depth-of-field photo extension. As shown in Figure 5, the width W of the entire profile is 5.9 mm, the height h is 1.9 mm, and the angle α between the cladding layer and the molten pool is 42° and β is 41°.

This method realizes rapid and accurate characterization of the cladding layer and molten pool morphology.

Claims (1)

1. A laser cladding layer and molten pool morphology characterization method are characterized in that the method first utilizes a wire cutting machine to cut the cladding substrate sample along the direction of the vertical cladding layer scanning path; then The cut matrix samples are polished on sandpaper of different particle sizes according to the method of metallographic sample preparation, and are polished in the order of particle size numbers from small to large; then the polished matrix samples are photographed with super depth of field; The radius of the arc is extended to draw the contour of the cladding layer and the molten pool in the ultra-depth-of-field photo, and record the radius of curvature of each arc; finally measure the width and height of the entire contour and the distance between the cladding layer and the molten pool The specific steps of the method are as follows: Step 1 Cut the substrate sample that has been clad Use a wire cutting machine to cut the clad substrate sample along the direction perpendicular to the scanning path of the cladding layer; Step 2 Grinding the cut matrix sample According to the metallographic sample preparation method, the cut matrix samples are polished on sandpaper of different particle sizes in order of particle size numbers from small to large; Step 3 Take photos with super depth of field Use the ultra-depth-of-field instrument to take pictures of the polished substrate samples; Step 4: Expand and draw the contours of the cladding layer and molten pool Utilize arcs with different radii of curvature to draw the contours of cladding layers and molten pools in ultra-depth-of-field photos, and record the radii of curvature of each arc; Step 5 Measure the morphology and profile of the cladding layer and molten pool Measure the width, height and angle between the cladding layer and the molten pool of the entire topographical outline drawn by the ultra-depth-of-field photo extension.