Online monitoring method for laser additive manufacturing

Abstract

The invention discloses an online monitoring method for laser additive manufacturing. The method includes the following steps that the center temperature of a molten pool and the diameter of the molten pool are collected in real time; and when the collected center temperature of the molten pool or the collected diameter of the molten pool does not conform to the pre-stored relationship of the laser power P, the center temperature of the molten pool and the diameter of the molten pool, the laser power P is adjusted according to the relationship so that the collected center temperature of the molten pool and the diameter of the molten pool conform to the pre-stored relationship of the laser power P, the center temperature of the molten pool and the diameter of the molten pool. By the application of the online monitoring method for laser additive manufacturing, online monitoring and control purposes are achieved, afterward detection is changed into intervening in the process, and the beneficial effects of good controllability and high machining efficiency are achieved. The online monitoring method can be better applied to large-size and large-area online monitoring in the field of ships, rail traffic and the like, the online monitoring method can better adapt to a flexible manufacturing environment, and more far-reaching practical significance is achieved.

Description

technical field

[0001] The invention relates to the technical field of additive manufacturing, and more specifically, to an online monitoring method for laser additive manufacturing. Background technique

[0002] The process of laser additive manufacturing is different from that of traditional materials. After casting, forging, and processing, traditional materials use X-ray, ultrasonic and other testing methods to determine whether the materials are qualified. Unqualified products are scrapped or welded. method to remedy. However, because laser additive manufacturing is produced by layer-by-layer stacking, it is significantly different from traditional manufacturing methods in terms of quality monitoring and monitoring.

[0003] For additive manufacturing, typically, each laser scan melts and resolidifies several layers of powder, typically 20 μm to several mm thick. After each laser shot, additional powder is scraped from the work area (powder spreading) or fresh powder ...

Examples

Embodiment 1

[0074] An online monitoring method for laser additive manufacturing containing a ceramic reinforced phase coating, comprising the following steps:

[0075] S1: Install and set up each device; specifically, multi-wavelength pyrometer, CCD high-speed infrared camera, laser processing head, laser power detector (with feedback and detection functions, used for power measurement and feedback, and automatic adjustment of power), CCD high-speed camera and protective gas pipeline are installed and set up according to the requirements;

[0076] S2: The test sample is placed at the designated position; here, Fe-based stainless steel powder is selected, and additive manufacturing is carried out on the Fe-based stainless steel 316L substrate. The strengthening phase is WC, and the proportion of WC in the strengthening phase is 2.5%, 5% and 10%. The method of feeding powder is adopted. The WC and Fe-based powders are uniformly mixed using a ball mill.

[0077] S3: Fixed laser scanning sp...

Embodiment 2

[0087] In this embodiment, the powder used is Ni-based alloy In625, the experimental substrate is 316 stainless steel, and the strengthening phase is TiC powder. The content of TiC in the period is 10%, 20%, 30%, and the difference with embodiment one is

[0088] In the acquisition stage of T1 parameters, the laser scanning speed is fixed (V=10mm.s -1 ) and laser powder feeding rate (Mp=10g / min, laser spot D=4mm and laser defocus amount F=0, keep the existing parameters of the equipment unchanged during the whole processing process, the same as below), change different laser power (P = 2000 ~ 500W) for experiments, using a temperature recorder to record the temperature of the center of the molten pool and using a CCD camera to record the diameter of the molten pool to obtain the temperature center data and diameter data of the molten pool under different laser powers; determine according to the criteria Effective relationship T1, the effective interval of the molten pool diam...

Embodiment 3

[0093] The difference between this embodiment and the first embodiment is that

[0094] The powder feeding method is used for laser additive manufacturing. The powder used is Co-based alloy Stellite6, the experimental substrate is 316 stainless steel, and the strengthening phase is TiN powder.

[0095] In the acquisition stage of T1 parameters, the laser scanning speed is fixed (V=10mm.s -1 ) and laser powder feeding rate (Mp=10g / min, laser spot D=4mm and laser defocus amount F=0, keep the existing parameters of the equipment unchanged during the whole processing process, the same as below), change different laser power (P=2000~500W) to carry out the experiment, adopt the temperature recorder to record the temperature of the melting pool center and utilize the CCD camera to record the melting pool shape, obtain the melting pool temperature center data and the melting pool diameter data under different laser powers; Determine the effective relationship T1. At this time, the ef...

technical field

[0001] The invention relates to the technical field of additive manufacturing, and more specifically, to an online monitoring method for laser additive manufacturing. Background technique

[0002] The process of laser additive manufacturing is different from that of traditional materials. After casting, forging, and processing, traditional materials use X-ray, ultrasonic and other testing methods to determine whether the materials are qualified. Unqualified products are scrapped or welded. method to remedy. However, because laser additive manufacturing is produced by layer-by-layer stacking, it is significantly different from traditional manufacturing methods in terms of quality monitoring and monitoring.

[0003] For additive manufacturing, typically, each laser scan melts and resolidifies several layers of powder, typically 20 μm to several mm thick. After each laser shot, additional powder is scraped from the work area (powder spreading) or fresh powder ...

Examples

Embodiment 1

[0074] An online monitoring method for laser additive manufacturing containing a ceramic reinforced phase coating, comprising the following steps:

[0075] S1: Install and set up each device; specifically, multi-wavelength pyrometer, CCD high-speed infrared camera, laser processing head, laser power detector (with feedback and detection functions, used for power measurement and feedback, and automatic adjustment of power), CCD high-speed camera and protective gas pipeline are installed and set up according to the requirements;

[0076] S2: The test sample is placed at the designated position; here, Fe-based stainless steel powder is selected, and additive manufacturing is carried out on the Fe-based stainless steel 316L substrate. The strengthening phase is WC, and the proportion of WC in the strengthening phase is 2.5%, 5% and 10%. The method of feeding powder is adopted. The WC and Fe-based powders are uniformly mixed using a ball mill.

[0077] S3: Fixed laser scanning sp...

Embodiment 2

[0087] In this embodiment, the powder used is Ni-based alloy In625, the experimental substrate is 316 stainless steel, and the strengthening phase is TiC powder. The content of TiC in the period is 10%, 20%, 30%, and the difference with embodiment one is

[0088] In the acquisition stage of T1 parameters, the laser scanning speed is fixed (V=10mm.s -1 ) and laser powder feeding rate (Mp=10g / min, laser spot D=4mm and laser defocus amount F=0, keep the existing parameters of the equipment unchanged during the whole processing process, the same as below), change different laser power (P = 2000 ~ 500W) for experiments, using a temperature recorder to record the temperature of the center of the molten pool and using a CCD camera to record the diameter of the molten pool to obtain the temperature center data and diameter data of the molten pool under different laser powers; determine according to the criteria Effective relationship T1, the effective interval of the molten pool diam...

Embodiment 3

[0093] The difference between this embodiment and the first embodiment is that

[0094] The powder feeding method is used for laser additive manufacturing. The powder used is Co-based alloy Stellite6, the experimental substrate is 316 stainless steel, and the strengthening phase is TiN powder.

[0095] In the acquisition stage of T1 parameters, the laser scanning speed is fixed (V=10mm.s -1 ) and laser powder feeding rate (Mp=10g / min, laser spot D=4mm and laser defocus amount F=0, keep the existing parameters of the equipment unchanged during the whole processing process, the same as below), change different laser power (P=2000~500W) to carry out the experiment, adopt the temperature recorder to record the temperature of the melting pool center and utilize the CCD camera to record the melting pool shape, obtain the melting pool temperature center data and the melting pool diameter data under different laser powers; Determine the effective relationship T1. At this time, the ef...

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