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Performance recovery is the main emphasis in most remanufactured machine tools, rather than the effective combination of customer requirements (CRs) and redesign processes. Because of this, remanufactured machine tools do not reach their potential competitiveness, highly restricting the implementations to recover used machine tools. To help remedy this, fuzzy nonlinear regression is applied to the fuzzy relationships between CRs and redesign parameters, and the fuzzy correlations among redesign parameters are analysed by fully considering the uncertainties between CRs and redesign parameters. Improved planning equations based on fuzzy nonlinear regression are proposed by injecting fuzziness into the original planning equations. The redesign process of a machine tool is taken as an example to implement the proposed method. The results show that the improved planning equations can obtain higher customer satisfaction compared to the unimproved planning equations. This can provide new thinking to effectively combine CRs and redesign processes. [ABSTRACT FROM AUTHOR]

The cladding layer formed by laser cladding is formed by solidification of the molten pool. The quality of the cladding layer is directly determined by the evolution of the molten pool. The numerical simulation of the evolution of the molten pool is carried out, revealing the relationship between different powers and the evolution of the molten pool. The results show that the volume of the molten pool exhibits a nonlinear expansion of "expansion-shrinkage-re-expansion" before reaching the steady state, and the volume and expansion rate of the molten pool are determined by the laser power. In addition, the degree of shrinkage of the molten pool and the speed of convection can also be controlled by the laser power. When the laser power reaches a certain level, evaporation occurs on the surface of the molten pool. The convection pattern of the molten pool can be changed by evaporation. However, due to the impact of shielding gas and Marangoni movement, the effect of evaporation on the geometry of the cladding layer is limited. [ABSTRACT FROM AUTHOR]

Because the convection pattern inside the laser cladding transient molten pool is difficult to measure by experimental means, the numerical analysis model of the inside of the laser cladding molten pool was constructed, and the forming mechanism of the cladding layer was simultaneously analyzed. The internal convection pattern of the single-track, multi-track and multi-layer laser cladding molten pool was analyzed. The results show that the convection inside the laser cladding molten pool in different types is mainly annular convection. The fluid at the bottom of the molten pool flows to the surface of the molten pool, and the fluid on the surface of the molten pool flows along the sides to the bottom of the molten pool. Therefore, the cladding layer is mainly solidified by the fluid flowing from the bottom of the molten pool to the surface of the molten pool. [ABSTRACT FROM AUTHOR]