Method for achieving adjusting and controlling of titanium alloy beta crystal grains obtained through laser additional material manufacturing

Abstract

The invention discloses a method for achieving adjusting and controlling of titanium alloy beta crystal grains obtained through laser additional material manufacturing. The method comprises the stepsthat a laser additional material manufacturing process window is preliminarily optimized, optimized process parameters are obtained, and under the optimized process window, the temperature field of amolten pool is calculated; the temperature gradient G and the cooling rate xi of the molten pool are extracted, and the G2 / xi value is worked out; the beta grain histomorphology is judged according tothe following rules, specifically, when xi is larger than or equal to 3*10<3> and smaller than or equal to 10<5> DEG C and G2 / xi is smaller than or equal to 1.2*10<6> DEG C s / m<2>, the beta grains are equiaxial grains, and when xi is smaller than or equal to 3*10<3> DEG C / s and G2 / xi is larger than or equal to 3*10<9> DEG C s / m<2>, the beta grains are columnar grains; the main process parameter sections of the equiaxial beta grains and the columnar beta grains are obtained; and finally, laser additional material manufacturing is conducted by adopting the corresponding process parameters, andparts controllable in beta grain histomorphology are obtained. According to the method, through molten pool temperature field simulation and solidification theory combination, achieving adjusting andcontrolling of the beta crystal grains are achieved, and the mechanical property of the formed parts can be effectively improved.

Description

technical field

[0001] The invention relates to the field of laser metal material processing, in particular to a method for realizing regulation of β grains of titanium alloy manufactured by laser additive manufacturing. Background technique

[0002] Laser additive manufacturing technology, also known as "laser metal 3D printing", is an advanced manufacturing technology that combines laser cladding with rapid prototyping technology. This technology is based on the principle of "layer-by-layer manufacturing and layer-by-layer accumulation". It can quickly form solid parts directly according to the 3D CAD model of the part. It has the characteristics of high material utilization rate, short production cycle, small forming restriction, and no mold required. In the direct forming of complex large-scale integral parts, the surface modification of parts and the direct customization of personalized products, it can also realize the rapid repair of damaged parts. It has broad applic...

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