Process Parameter Optimization of Ti-45Nb Titanium Alloy Produced Using the Design of Experiments Technique

The goal of this study is to optimize the production conditions of Ti-45Nb titanium alloy by innovatively introducing the Design of Experiments (DOE) method and using the 2k method of full factor analysis in DOE, and to improve the chemical heterogeneity of Ti-45Nb titanium alloy by analyzing and optimizing the parameter conditions of the production process and a total of 32 experiments was conducted. Ti-45Nb titanium alloy was produced by vacuum arc remelting (VAR) according to the following process parameters. The titanium alloy products obtained from each production were cut into circular samples with a diameter of 16 cm, and the chemical inhomogeneity was measured by Energy-dispersive X-ray spectroscopy using the 5-point sampling method. Then, the chemical inhomogeneity data values were entered into the previous experimental design, and the appropriate factor levels were determined using the technology provided in the Minitab statistical software package, with a significance level of 0.05 (α = 0.05). Through full factorial design (DOE) and residual analysis, a regression model for chemical inhomogeneity was successfully constructed. After optimization, the production conditions of Ti-45Nb titanium alloy are: Smelting current (KA) = 1.7, Current coil (A) = 3.2542, Transform time (S) = 6, Inlet water temperature (°C) = 25, and Water flow (L/min) = 220. The chemical inhomogeneity value of the produced Ti-45Nb titanium alloy is theoretically 10%. It can provide a reference for enterprise production.