Laser shock peening method for additive manufactured component of double-phase titanium alloy

Abstract

A laser shock peening method for an additive manufactured component of a double-phase titanium alloy is provided. First, a three-dimensional digital model of a complex component is obtained, and the model is divided into a plurality of slices; a forming direction of a formed part in an additive manufacturing process is determined according to a stress direction of the additive manufactured component in an engineering application; then, the component of the double-phase titanium alloy is formed and manufactured by selective laser melting, and orientations of a C-axis of an α phase is allowed to be consistent through adjustment and control; and finally, laser shock peening is performed on all outer surfaces of the high-performance additive manufactured component of the double-phase titanium alloy by inducing a high-intensity shock wave to act in an acting direction which forms an angle in a predetermined range with the C-axis of the α phase.

Claims

1. A laser shock peening method for an additive manufactured component of a double-phase titanium alloy comprising the following steps: (1) obtaining a three-dimensional digital model of a complex component through a computer software, and dividing the model into a plurality of slices; (2) determining a forming direction in the process according to a load direction of the additive manufactured component in an engineering application, and then making an additive forming surface parallel to the load direction; (3) then, forming the component of the double-phase titanium alloy by selective laser melting, and allowing the orientations of a C-axis of an α phase to be consistent through continuously applying a strong magnetic field generated by a spiral superconducting coil to a metal melt; (4) performing the laser shock peening with a normal of the C-axis as a symmetry axis by forming an incident angle, namely, an angle α, between an acting direction of a laser shock wave and the C-axis of the α phase on each of left and right sides; and (5) performing the laser shock peening on all outer surfaces of the additive manufactured component of the double-phase titanium alloy.

2. The laser shock peening method for the additive manufactured component of the double-phase titanium alloy according to claim 1, wherein in step (3), an intensity of the strong magnetic field is ≥6 T, and parameters of the selective laser melting comprise: a spot diameter of 80 μm, a laser wavelength of 1.06 to 1.10 μm, a laser power of 200 to 1000 W, a scanning speed of 500 to 1000 mm/s, and a powder layer thickness of 0.02 to 0.5 mm.

3. The laser shock peening method for the additive manufactured component of the double-phase titanium alloy according to claim 1, wherein in step (4), 0°<α<30°.

4. The laser shock peening method for the additive manufactured component of the double-phase titanium alloy according to claim 1, wherein in step (5), ranges of process parameters of the laser shock peening comprise: a laser pulse energy of 3 to 12 J, a pulse width of 5 to 20 ns, a spot diameter of 1 to 3 mm, and an overlap ratio in transverse and longitudinal directions each being 30% to 50%.

5. The laser shock peening method for the additive manufactured component of the double-phase titanium alloy according to claim 1, wherein a material of the component of the double-phase titanium alloy comprises a near-a titanium alloy such as TC1, TC4, and TC6.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In order to illustrate the technical solutions in the embodiments of the present application or in the prior art more clearly, the accompanying drawings to be used in the description of the examples or the prior art will be introduced briefly below.

(2) FIG. 1 is a schematic view of a C-axis of an α phase of a double-phase titanium alloy.

(3) FIG. 2 is a schematic view illustrating that the additive forming surface is parallel to the stress direction in the additive manufacturing process of the present invention.

(4) FIG. 3 is a schematic view illustrating that the C-axis of the α phase is subjected to laser shock peening in the present invention.

(5) FIG. 4 is a schematic view of the turbine blade in the embodiments of the present invention.

(6) Table 1 is a comparison of fatigue life of the turbine blades at different states in the embodiments of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(7) The specific implementations of the present invention are illustrated in detail below with reference to the accompanying drawings and embodiments, but the present invention should not be limited to the embodiments.

(8) A turbine blade of double-phase TC4 titanium alloy is used in these embodiments.

Embodiment 1

(9) 1) Three-dimensional point cloud data on the turbine blade surface is obtained through a three-dimensional laser scanner, and then, a three-dimensional digital model of the turbine blade is obtained through the computer software, and the model is divided into a plurality of slices;

(10) 2) simulation analysis is performed through a simulation software to obtain the stress direction distribution of TC4 turbine blade in the actual application, and the additive direction in the additive manufacturing process is determined, so that the additive forming surface is parallel to the stress direction;

(11) 3) then, the turbine blade is formed and manufactured by selective laser melting, where parameters of selective laser melting include: a spot diameter of 80 μm, a laser wavelength of 1.08 μm, a laser power of 300 W, a scanning speed of 700 mm/s, and a powder layer thickness of 0.3 mm. A vibration fatigue test is performed on the formed turbine blade.

Embodiment 2

(12) 1) Three-dimensional point cloud data on the turbine blade surface is obtained through a three-dimensional laser scanner, and then, a three-dimensional digital model of the turbine blade is obtained through the computer software, and the model is divided into a plurality of slices;

(13) 2) simulation analysis is performed through a simulation software to obtain the stress direction of TC4 turbine blade in the actual application, and the additive direction in the additive manufacturing process is determined, so that the additive forming surface is parallel to the stress direction;

(14) 3) then, the turbine blade is formed and manufactured by selective laser melting, where parameters of selective laser melting include: a spot diameter of 80 μm, a laser wavelength of 1.08 μm, a laser power of 300 W, a scanning speed of 700 mm/s, and a powder layer thickness of 0.3 mm;

(15) 4) finally, laser shock peening is directly performed on the surface of the turbine blade, where ranges of process parameters of laser shock peening include: a laser pulse energy of 10 J, a pulse width of 10 ns, a spot diameter of 3 mm, and an overlap ratio in the transverse and longitudinal directions each being 500%. A vibration fatigue test is performed on the strengthened turbine blade.

Embodiment 3

(16) 1) Three-dimensional point cloud data on the turbine blade surface is obtained through a three-dimensional laser scanner, and then, a three-dimensional digital model of the turbine blade is obtained through the computer software, and the model is divided into a plurality of slices;

(17) 2) simulation analysis is performed through a simulation software to obtain the stress direction of TC4 turbine blade in the actual application, and the additive direction in the additive manufacturing process is determined, so that the additive forming surface is parallel to the stress direction;

(18) 3) then, the turbine blade is formed and manufactured by selective laser melting, and the orientations of a C-axis of an α phase is allowed to be consistent through continuously applying a strong magnetic field of 9 T generated by a spiral superconducting coil to a metal melt, where parameters of selective laser melting include: a spot diameter of 80 μm, a laser wavelength of 1.08 μm, a laser power of 300 W, a scanning speed of 700 mm/s, and a powder layer thickness of 0.3 mm;

(19) 4) as shown in FIG. 3, finally, laser shock peening is performed with the normal of the C-axis as a symmetry axis by forming an angle α of 30°<α<60° or 60°<α<90° between the laser shock wave and the C-axis of the α phase on each of left and right sides, where ranges of process parameters of laser shock peening include; a laser pulse energy of 10 J, a pulse width of 10 ns, a spot diameter of 3 mm, and an overlap ratio in the transverse and longitudinal directions each being 50%. A vibration fatigue test is performed on the strengthened turbine blade.

Embodiment 4

(20) The technical solution of the present invention: referring to FIG. 1, FIG. 2, FIG. 3, and FIG. 4, this embodiment relates to a laser shock peening method for additive manufactured component of the double-phase titanium alloy, which includes the following steps:

(21) 1) obtaining three-dimensional point cloud data on the turbine blade surface through a three-dimensional laser scanner, and then, obtaining a three-dimensional digital model of the turbine blade through the computer software, and dividing the model into a plurality of slices;

(22) 2) performing simulation analysis through a simulation software to obtain the stress direction of TC4 turbine blade in the actual application, and determining the additive direction in the additive manufacturing process, so that the additive forming surface is parallel to the stress direction;

(23) 3) then, forming and manufacturing the turbine blade by selective laser melting, and allowing the orientations of the C-axis of the α phase to be consistent through continuously applying a strong magnetic field of 9 T generated by a spiral superconducting coil to a metal melt, where parameters of selective laser melting include: a spot diameter of 80 μm, a laser wavelength of 1.08 μm, a laser power of 300 W, a scanning speed of 700 mm/s, and a powder layer thickness of 0.3 mm;

(24) 4) as shown in FIG. 3, finally, performing laser shock peening with the normal of the C-axis as a symmetry axis by forming an angle α of 0°<α≤30° between the laser shock wave and the C-axis of the α phase on each of left and right sides, where ranges of process parameters of laser shock peening include: a laser pulse energy of 10 J, a pulse width of 10 ns, a spot diameter of 3 mm, and an overlap ratio in the transverse and longitudinal directions each being 50%. A vibration fatigue test is performed on the strengthened turbine blade.

(25) It can be seen from Table 1 that in vibration fatigue life tests at four different states of Embodiment 1 (1-1, 1-2), Embodiment 2 (2-1, 2-2), Embodiment 3 (3-1 (30°<α≤60°), 3-2 (30°<α≤60°), 3-3 (60°<α≤90°), 3-4 (60°<α≤90°)), and Embodiment 4 (4-1, 4-2), under different stress conditions of 430 MPa and 560 MPa, the results show that the turbine blade processed using the technical solution of the present invention has significantly improved fatigue life, thereby achieving the optimal strengthening effect.

(26) The above disclosure is merely a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention shall still belong to the scope of the present invention.

(27) TABLE-US-00001 TABLE 1 State Stress/MPa Fatigue life 1-1 (Embodiment 1) 430 2.49 × 10.sup.7 1-2 (Embodiment 1) 560 1.23 × 10.sup.7 2-1 (Embodiment 2) 430   3 × 10.sup.7 2-2 (Embodiment 2) 560 2.49 × 10.sup.7 3-1 (30° < α ≤ 60°) (Embodiment 3) 430 3.26 × 10.sup.7 3-2 (30° < α ≤ 60°) (Embodiment 3) 560 2,86 × 10.sup.7 3-3 (60° < α ≤ 90°) (Embodiment 3) 430 3.41 × 10.sup.7 3-4 (60° < α ≤ 90°) (Embodiment 3) 560 2.95 × 10.sup.7 4-1 (Embodiment 4) 430 3.71 × 10.sup.7 4-2 (Embodiment 4) 560 3.38 × 10.sup.7