Research On Blade Manufacturing Process And Performance Based On Laser Cladding Technology

Due to its high forming efficiency and the remarkable characteristics of forming complex structural parts and hollow structural parts,additive manufacturing technology has received national attention and vigorous development.As a kind of additive manufacturing technology,laser cladding technology has the characteristics of simple processing equipment and high forming efficiency.Great attention has been paid in the fields of biomedicine;aerospace and automobile manufacturing.As one of the main common parts in the power system,the impeller plays an important role in the high-end manufacturing fields such as automobile manufacturing and aerospace.In the current manufacturing industry,the manufacture of impellers is still dominated by conventional turning and milling,but the blades of the impellers are often thin-walled parts with complex shapes,and the conventional processing technology still has its limitations.Therefore,in view of this situation,this paper uses the combination of theory and experiment to establish the theoretical model of the basic process and conduct the basic process parameter test.In order to increase the maximum machining inclination angle,a tilting process is proposed.In order to ensure the machining efficiency and machining accuracy at the same time,a variable parameter path scanning method based on laser cladding technology is proposed.Finally,the blade model is processed by the combined processing method of increasing and decreasing materials,and ’the performance of laser cladding specimens is tested.The main contents of the research are as follows:(1)Introduced the background and significance of laser cladding technology,researched and analyzed the research status of laser cladding technology at home and abroad,and proposed the current technical bottleneck and future development of laser cladding technology.The research direction and content of this topic.(2)Several basic process parameters for laser cladding manufacturing include laser power,powder feeding amount,scanning speed,lifting amount and lap ratio.In this paper,the basic theoretical model of process parameters is first established.Then,for several major basic process parameters,single-channel single-layer,single-channel multi-layer and multi-channel single-layer tests are designed.The evaluation method of the single-channel single-layer test is the contact angle between the cladding layer and the substrate.The larger the contact angle,the better the bonding effect between the cladding layer and the substrate.The evaluation criteria for a single-channel multilayer test is the error between the actual machining height and the theoretical machining height.Evaluation criteria for multi-channel single-layer tests This paper proposes two methods:standard deviation method and positive evaluation method.Finally,the optimal process parameters were determined by the process parameter test.(3)Since the impeller blades tend to have inclined characteristics,the maximum tilting angle of the laser cladding to manufacture the inclined thin-walled parts is studied.In the laser cladding technique,the tilt characteristic is achieved by the offset between the layers.When the tilt angle is increased,the interlayer shift is also increased.When the offset is too large,the unsupported portion of the powder collapses.Therefore,the maximum tilt angle of laser cladding processing is improved by presetting the process tilt angle.(4)Due to the processing capability of the equipment,when the machining path is too complicated,the improper scanning speed makes the position of the laser head unable to maintain accuracy,which leads to a decrease in machining accuracy.Therefore,the processing of complex path segments requires a proper reduction in scanning speed.If the low-speed scanning is used globally,the processing efficiency will be greatly affected.When the local scanning speed is reduced,the energy density becomes larger,which affects the processing quality.Therefore,it is necessary to maintain the processing quality by adjusting the laser power and the powder feeding amount..For this reason,a variable parameter processing path scanning method based on laser cladding technology is proposed in this paper,which improves the processing efficiency under the premise of ensuring the processing precision.(5)At the end of the paper,the processing of the designed impeller blades was completed by the combined processing method of increasing and decreasing materials.First,the blade blank is processed by laser cladding technology,and then the blade is reworked by milling.The dimensional accuracy of the processed blade was analyzed,and the tensile strength and hardness of the laser cladding test specimen were analyzed.