In order to study the modular design of computer numerical control machine tools oriented to customer demands, the customer demand information model was established based on rough analytic hierarchy process and information entropy by analyzing and transforming customer demands. Based on the domain mapping method of axiomatic design and quality function deployment integration, the product function model and structure model of computer numerical control machine tools are established. Based on fuzzy clustering analysis, the module division of computer numerical control machine tools is studied, and the dynamic clustering diagram of computer numerical control machine tools is formed with MATLAB as the operating environment. Based on Technique for Order Preference by Similarity to Ideal Solution method, the scheme of computer numerical control machine tools module division is evaluated. Taking the horizontal computer numerical control machine tool products of Shenyang Machine Tool Group as an example, the module division is carried out. The example design and the result analysis prove that the module division system is very effective and fast.

Microalloying vanadium can change the segregation state of Nb element in IN718 alloy, reduce the formation of harmful Laves phase and refine the dendritic structure of IN718 alloy during the laser process. Therefore, IN718 alloys with V content from 0.081 to 1.88 wt.% were prepared and evaluated. Metallographic microscopy and scanning electron microscopy were used to observe the corresponding morphology, structure, and distribution of elements. First of all, it was found that the addition of V refines the grain size of IN718 alloy and reduces the primary dendrite arm spacing. Secondly, adding V to IN718 alloy can reduce the porosity of the cladding layer. The elements are uniformly distributed in the cladding layer, and the addition of vanadium reduces the segregation degree of the Nb element, which is conducive to homogenization. In addition, microhardness and residual stress were also investigated. Finally, the addition of vanadium was shown to have no apparent effect on the tensile strength and yield strength but can significantly improve the elongation of IN718 alloy. In conclusion, the microstructure and mechanical properties of IN718 alloy with 0.081 wt.% vanadium content provide a new solution to improve the application level of IN718 alloy in laser cladding.

The finite element model (FE) of temperature field of straight thin-walled samples in laser cladding IN718 was established, and the growth of microstructure was simulated by cellular automata (CA) method through macro-micro coupling (CA-FE). The effects of different cooling conditions on microstructure, hardness, and properties of laser-cladding layer were studied by designing cooling device. The results show that the simulation results are in good agreement with the microstructure of the cladding layer observed by the experiment. With the scanning strategy of reducing laser power layer-by-layer, the addition of water cooling device and the processing condition of 0.7 mm Z-axis lift, excellent thin-walled parts can be obtained. With the increase of cladding layers, the pool volume increases, the temperature value increases, the temperature gradient, cooling rate, solidification rate, K value gradually decrease, and eventually tend to be stable, in addition, the hardness shows a fluctuating downward trend. Under the processing conditions of layer-by-layer power reduction and water cooling device, the primary dendrite arm spacing reduced to about 8.3 μm, and the average hardness at the bottom of cladding layer increased from 260 HV to 288 HV. The yield strength and tensile strength of the tensile parts prepared under forced water cooling increased to a certain extent, while the elongation slightly decreased.