Boron-containing titanium-based composite powder for 3D printing and method of preparing same

Abstract

This invention discloses a boron-containing titanium-based composite powder for 3D printing, consisting of 0.5%-2% by weight of titanium diboride and 98%-99.5% by weight of titanium sponge. The invention further discloses a method of preparing such composite powder, where the element boron is introduced to the titanium powder through rapid solidification, which significantly improves the solid solubility of boron in Ti, enabling the introduction of part of the boron into the titanium matrix to form supersaturated solid solutions. The reinforcement phase TiB in the boron-containing titanium-based composite powder prepared herein can be precisely controlled in grain size ranging from the nanometer scale to the micrometer scale through temperature or energy density, thereby preparing the titanium-based composite materials with different sizes of reinforcement phases to meet different mechanical requirements.

Claims

1. A boron-containing titanium-based composite powder for 3D printing, consisting of 0.5%-2% by weight of titanium diboride and 98%-99.5% by weight of titanium sponge; wherein the boron-containing titanium-based composite powder has an internal nano quasi-continuous network structure formed by titanium monoboride whisker (TiBw) and titanium (Ti) crystal grains; the quasi-continuous network structure has a size of 2-3 μm, and TiBw has a particle size of 8-15 nm; the boron-containing titanium-based composite powder is prepared by a method comprising the following steps: (1) mixing 0.5%-2% by weight of the titanium diboride with 98%-99.5% of the titanium sponge to produce a powder mixture; (2) pressing the powder mixture by a hydraulic press into a consumable electrode with a size of 300×60×60 mm; (3) performing vacuum melting twice on the consumable electrode to obtain a composite ingot with a diameter of 170 mm; (4) polishing the composite ingot; heating the polished ingot to a first temperature in a high-temperature furnace; keeping the polished ingot at the first temperature; subjecting the heated composite ingot to billet forging using a 1-ton air hammer to obtain a bar A; polishing the bar A and heating the polished bar A to a second temperature in the high-temperature furnace; keeping the polished bar A at the second temperature; forging the heated bar A using a radial forging machine to obtain a bar B; mechanically processing the bar B to produce a composite titanium-based bar C with a size of 41 mm×400 mm; and (5) subjecting the composite titanium-based bar C to electrode induction melting ultrasonic gas atomization to prepare the boron-containing titanium-based composite powder.

2. The boron-containing titanium-based composite powder of claim 1, wherein the hydraulic press in step (2) is a 630-ton hydraulic press.

3. The boron-containing titanium-based composite powder of claim 1, wherein in step (4), a diameter of the bar A is 100 mm; a diameter of the bar B is 45 mm; and the bar C has a conical front end.

4. The boron-containing titanium-based composite powder of claim 1, wherein in step (4), the first temperature is 1000-1050° C. and the polished ingot is kept at 1000-1050° C. for 2 h; the second temperature is 950° C. and the polished bar A is kept at 950° C. for 2 h; and the radial forging machine is a SKK-14 forging machine.

5. The boron-containing titanium-based composite powder of claim 1, wherein the boron-containing titanium-based composite powder obtained in step (5) is subjected to heat treatment by a Sparking Plasma Sintering device.

6. The boron-containing titanium-based composite powder of claim 5, wherein the heat treatment is performed at 750-1000° C., and then the boron-containing titanium-based composite powder is kept at 750-1000° C. for 15 min.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is an XRD pattern of a boron-containing titanium-based composite powder prepared in the invention.

(2) FIG. 2 is a scanning electron micrograph showing the boron-containing titanium-based composite powder of the invention.

(3) FIG. 3 is a scanning electron micrograph showing enlarged spherical surfaces of the boron-containing titanium-based composite powder of the invention.

(4) FIG. 4 is a scanning electron micrograph showing the cross-section micromorphology of the boron-containing titanium-based composite powder of the invention.

(5) FIG. 5 is a scanning electron micrograph showing the morphology of the boron-containing titanium-based composite powder after heat-treated at 750° C.

(6) FIG. 6 is a scanning electron micrograph showing the morphology of the boron-containing titanium-based composite powder after heat-treated at 850° C.

(7) FIG. 7 is a scanning electron micrograph showing the morphology of the boron-containing titanium-based composite powder after heat-treated at 950° C.

(8) FIG. 8 is a scanning electron micrograph showing the morphology of the boron-containing titanium-based composite powder after heat-treated at 1000° C.

DETAILED DESCRIPTION OF EMBODIMENTS

(9) This invention will be described in detail below with reference to the accompanying drawings and embodiments.

(10) The invention provides a TiBw/Ti composite powder for 3D printing consisting of 0.5%-2% by weight of titanium diboride and 98%-99.5% by weight of titanium sponge, where the composition of respective raw materials is specifically shown in Table 1.

(11) TABLE-US-00001 TABLE 1 Compositions of the titanium diboride and the titanium sponge Titanium Element Ti Fe Si Cl C N O H sponge Content ≥99.8 0.01 <0.01 0.06 0.008 0.003 0.046 0.0007 (wt. %) TiBw.sub.2 Element Ti B Fe Si C / / / Content 66.97 32.6 0.065 0.01 0.36 / / / (wt. %)

(12) The invention also provides a method of preparing the TiB/Ti composite powder for 3D printing, including:

(13) (1) 0.5%-2% by weight of the titanium diboride and 98%-99.5% by weight of the titanium sponge were respectively prepared and uniformly mixed to obtain a powder mixture.

(14) (2) The powder mixture was pressed into a consumable electrode with a size of 300×60×60 mm by a 630-ton hydraulic press.

(15) (3) Vacuum melting was performed twice on the consumable electrode to obtain a composite ingot with a diameter of 170 mm, where the element B was derived from the titanium diboride, and the element Ti was derived from the titanium sponge.

(16) (4) The composite ingot was polished and heated to 1000-1050° C. in a high-temperature furnace, and kept at 1000-1050° C. for 2 h. The heated composite ingot was subjected to billet forging using a 1-ton air hammer to obtain a bar A with a diameter of 100 mm. The bar A was polished and heated to 950° C. in the high-temperature furnace and kept at 950° C. for 2 h. The bar A was forged using a SKK-14 radial forging machine to obtain a bar B with a diameter of 45 mm, and then the bar B was mechanically processed to produce a composite titanium-based bar C with a size of 41 mm×400 mm and a conical front end.

(17) (5) The composite titanium-based bar C was subjected to electrode induction melting ultrasonic gas atomization to prepare the boron-containing titanium-based composite powder.

(18) During the powder preparation by gas atomization, the rapid solidification involved can significantly improve the solid solubility of boron atoms (derived from TiB.sub.2) in Ti, allowing part of the boron atoms to be introduced into the titanium matrix to form supersaturated solid solutions, and other boron atoms to form nano TiBw to uniformly distribute in the titanium matrix.

(19) The boron-containing titanium-based composite powder prepared above is subjected to heat treatment.

(20) Specifically, the boron-containing titanium-based composite powder obtained in step (5) is subjected to heat treatment at 750-1000° C. using a Sparking Plasma Sintering (SPS) device, and then kept at 750-1000° C. for 15 min to obtain the TiB/Ti composite powder with different sizes of the reinforcement phase.

(21) The boron-containing titanium-based composite powder prepared herein can be directly used for 3D printing to produce TiBw/Ti composite materials without undergoing the conventional mechanical mixing in the preparation of the powder mixture for 3D printing, avoiding the damage to spherical powder sphericity and the introduction of impurities. The reinforcement phase TiBw in the TiBw/Ti composite materials is controllable in size. The rapid solidification involved in gas atomization can significantly improve the solid solubility of boron atoms (derived from TiB.sub.2) in Ti, allowing part of the boron atoms to be introduced into the titanium matrix to form supersaturated solid solutions. The boron-containing titanium-based composite powder is subjected to heat treatment at different temperature to allow the occurrence of in situ reaction between boron and titanium to produce the reinforcement phase TiBw, where the reinforcement phase TiBw can be precisely controlled in grain size ranging from the nanometer scale to the micrometer scale through temperature or energy density, thereby preparing the TiBw/Ti composite materials with different grain sizes of TiBw by 3D printing to meet different mechanical requirements.

(22) FIG. 1 is an XRD pattern showing the phase analysis of the boron-containing titanium-based composite powder. It can be seen that the composite powder is predominated by Ti and TiBw, where the TiBw diffraction peak is not obvious, which is mainly caused by the small molecular weight and low content of element B.

(23) FIG. 2 shows the surface morphology of the boron-containing titanium-based composite powder prepared in the invention. It can be seen that the composite powder has good sphericity and smooth surface, and no satellite powder is observed.

(24) FIG. 3 is an enlarged view of surfaces of the spherical powder. It can be seen that there are no cracks and holes on the surfaces.

(25) FIG. 4 shows the cross-section micromorphology of the composite powder. It can be seen that in the composite powder, small TiBw crystal whiskers are formed and distributed at grain boundaries.

(26) FIG. 5 shows the morphology of the boron-containing titanium-based composite powder after heat-treated at 750° C., where TiBw is mainly distributed at the grain boundaries, and is relatively tiny with a particle size of 100 nm or less.

(27) FIG. 6 shows the morphology of the boron-containing titanium-based composite powder after heat-treated at 850° C., where the TiBw crystal whiskers grow with the increase of the temperature, and have particle sizes of 200-300 nm at 850° C.

(28) FIG. 7 shows the morphology of the boron-containing titanium-based composite powder after heat-treated at 950° C., where the TiBw crystal whiskers grow to a particle size of 2-3 μm.

(29) FIG. 8 shows the morphology of the boron-containing titanium-based composite powder after heat-treated at 1000° C., where the TiBw crystal whiskers grow to a particle size of 5 μm or more.

EXAMPLE 1

(30) Provided herein was a method of preparing a TiBw/Ti composite powder for 3D printing, which was specifically described as follows.

(31) (1) Preparation of Powder Mixture

(32) 0.5% by weight of titanium diboride and 99.5% by weight of titanium sponge were respectively prepared and then mixed uniformly to produce a powder mixture, where the element B was derived from TiB.sub.2, and compositions of the titanium diboride and the titanium sponge were shown in Table 1.

(33) (2) Preparation of Consumable Electrode

(34) The powder mixture was pressed into a consumable electrode with a size of 300×60×60 mm by a 630-ton hydraulic press.

(35) (3) Melting

(36) The consumable electrode was subjected to vacuum melting twice to obtain a composite ingot with a diameter of 170 mm, where the element B was derived from the titanium diboride, and the element Ti was derived from the titanium sponge.

(37) (4) Preparation of a Titanium-Based Composite Bar

(38) The composite ingot was polished, heated to 1000-1050° C. in a high-temperature furnace and kept at 1000-1050° C. for 2 h. Then the composite ingot was subjected to billet forging using a 1-ton air hammer to obtain a bar A with a diameter of 100 mm. The bar A was polished and heated to 950° C. in the high-temperature furnace and kept at 950° C. for 2 h. The bar A was forged using a SKK-14 radial forging machine into a bar B with a diameter of 45 mm, and then the bar B was mechanically processed to produce a composite titanium-based bar C with a size of 41 mm×400 mm and a conical front end.

(39) (5) The composite titanium-based bar C was subjected to electrode induction melting ultrasonic gas atomization to prepare the boron-containing titanium-based composite powder.

(40) The boron-containing titanium-based composite powder obtained above was subjected to heat treatment at 1000° C. under an argon atmosphere using a Sparking Plasma Sintering (SPS) device and kept at 1000° C. for 15 min.

EXAMPLE 2

(41) Provided herein was a method of preparing a TiB/Ti composite powder for 3D printing, which was specifically described as follows.

(42) (1) Preparation of Powder Mixture

(43) 1% by weight of titanium diboride and 99% by weight of titanium sponge were respectively prepared and then mixed uniformly to produce a powder mixture, where the element B was derived from TiB.sub.2, and compositions of the titanium diboride and the titanium sponge were shown in Table 1.

(44) (2) Preparation of Consumable Electrode

(45) The powder mixture was pressed into a consumable electrode with a size of 300×60×60 mm by a 630-ton hydraulic press.

(46) (3) Melting

(47) The consumable electrode was subjected to vacuum melting twice to obtain a composite ingot with a diameter of 170 mm, where the element B was derived from the titanium diboride, and the element Ti was derived from the titanium sponge.

(48) (4) Preparation of a Titanium-Based Composite Bar

(49) The composite ingot was polished, heated to 1000-1050° C. in a high-temperature furnace and kept at 1000-1050° C. for 2 h. Then the composite ingot was subjected to billet forging using a 1-ton air hammer to obtain a bar A with a diameter of 100 mm. The bar A was polished and heated to 950° C. in the high-temperature furnace and kept at 950° C. for 2 h. The bar A was forged using a SKK-14 radial forging machine into a bar B with a diameter of 45 mm, and then the bar B was mechanically processed to produce a composite titanium-based bar C with a size of 41 mm×400 mm and a conical front end.

(50) (5) The composite titanium-based bar C was subjected to electrode induction melting ultrasonic gas atomization to prepare the boron-containing titanium-based composite powder.

(51) The boron-containing titanium-based composite powder obtained above was subjected to heat treatment at 850° C. under an argon atmosphere using a Sparking Plasma Sintering (SPS) device and kept at 850° C. for 15 min.

EXAMPLE 3

(52) A TiB/Ti composite powder for 3D printing was prepared through the following steps.

(53) (1) 2% by weight of titanium diboride and 98% by weight of titanium sponge were respectively prepared and then mixed uniformly to produce a powder mixture, where the element B was derived from TiB.sub.2, and compositions of the titanium diboride and the titanium sponge were shown in Table 1.

(54) (2) Preparation of Consumable Electrode

(55) The powder mixture was pressed into a consumable electrode with a size of 300×60×60 mm by a 630-ton hydraulic press.

(56) (3) Melting

(57) The consumable electrode was subjected to vacuum melting twice to obtain a composite ingot with a diameter of 170 mm, where the element B was derived from the titanium diboride, and the element Ti was derived from the titanium sponge.

(58) (4) Preparation of a Titanium-Based Composite Bar

(59) The composite ingot was polished, heated to 1000-1050° C. in a high-temperature furnace and kept at 1000-1050° C. for 2 h. Then the composite ingot was subjected to billet forging using a 1-ton air hammer to obtain a bar A with a diameter of 100 mm. The bar A was polished and heated to 950° C. in the high-temperature furnace and kept at 950° C. for 2 h. The bar A was forged using a SKK-14 radial forging machine into a bar B with a diameter of 45 mm, and then the bar B was mechanically processed to produce a composite titanium-based bar C with a size of 41 mm×400 mm and a conical front end.

(60) (5) The composite titanium-based bar C was subjected to electrode induction melting ultrasonic gas atomization to prepare the boron-containing titanium-based composite powder.

(61) The boron-containing titanium-based composite powder obtained above was subjected to heat treatment at 750° C. under an argon atmosphere using a Sparking Plasma Sintering (SPS) device and kept at 750° C. for 15 min.

EXAMPLE 4

(62) A TiB/Ti composite powder for 3D printing was prepared through the following steps.

(63) (1) 2% by weight of titanium diboride and 98% by weight of titanium sponge were respectively prepared and then mixed uniformly to produce a powder mixture, where the element B was derived from TiB.sub.2, and compositions of the titanium diboride and the titanium sponge were shown in Table 1.

(64) (2) Preparation of Consumable Electrode

(65) The powder mixture was pressed into a consumable electrode with a size of 300×60×60 mm by a 630-ton hydraulic press.

(66) (3) Melting

(67) The consumable electrode was subjected to vacuum melting twice to obtain a composite ingot with a diameter of 170 mm, where the element B was derived from the titanium diboride, and the element Ti was derived from the titanium sponge.

(68) (4) Preparation of a Titanium-Based Composite Bar

(69) The composite ingot was polished, heated to 1000-1050° C. in a high-temperature furnace and kept at 1000-1050° C. for 2 h. Then the composite ingot was subjected to billet forging using a 1-ton air hammer to obtain a bar A with a diameter of 100 mm. The bar A was polished and heated to 950° C. in the high-temperature furnace and kept at 950° C. for 2 h. The bar A was forged using a SKK-14 radial forging machine into a bar B with a diameter of 45 mm, and then the bar B was mechanically processed to produce a composite titanium-based bar C with a size of 41 mm×400 mm and a conical front end.

(70) (5) The composite titanium-based bar C was subjected to electrode induction melting ultrasonic gas atomization to prepare the boron-containing titanium-based composite powder.

(71) The boron-containing titanium-based composite powder obtained above was subjected to heat treatment at 850° C. under an argon atmosphere using a Sparking Plasma Sintering (SPS) device and kept at 850° C. for 15 min.

EXAMPLE 5

(72) A TiB/Ti composite powder for 3D printing was prepared through the following steps.

(73) (1) 2% by weight of titanium diboride and 98% by weight of titanium sponge were respectively prepared and then mixed uniformly to produce a powder mixture, where the element B was derived from TiB.sub.2, and compositions of the titanium diboride and the titanium sponge were shown in Table 1.

(74) (2) Preparation of Consumable Electrode

(75) The powder mixture was pressed into a consumable electrode with a size of 300×60×60 mm by a 630-ton hydraulic press.

(76) (3) Melting

(77) The consumable electrode was subjected to vacuum melting twice to obtain a composite ingot with a diameter of 170 mm, where the element B was derived from the titanium diboride, and the element Ti was derived from the titanium sponge.

(78) (4) Preparation of a Titanium-Based Composite Bar

(79) The composite ingot was polished, heated to 1000-1050° C. in a high-temperature furnace and kept at 1000-1050° C. for 2 h. Then the composite ingot was subjected to billet forging using a 1-ton air hammer to obtain a bar A with a diameter of 100 mm. The bar A was polished and heated to 950° C. in the high-temperature furnace and kept at 950° C. for 2 h. The bar A was forged using a SKK-14 radial forging machine into a bar B with a diameter of 45 mm, and then the bar B was mechanically processed to produce a composite titanium-based bar C with a size of 41 mm×400 mm and a conical front end.

(80) (5) The composite titanium-based bar C was subjected to electrode induction melting ultrasonic gas atomization to prepare the boron-containing titanium-based composite powder.

(81) The boron-containing titanium-based composite powder obtained above was subjected to heat treatment at 950° C. under an argon atmosphere using a Sparking Plasma Sintering (SPS) device and kept at 950° C. for 15 min.

EXAMPLE 6

(82) A TiB/Ti composite powder for 3D printing was prepared through the following steps.

(83) (1) 2% by weight of titanium diboride and 98% by weight of titanium sponge were respectively prepared and then mixed uniformly to produce a powder mixture, where the element B was derived from TiB.sub.2, and compositions of the titanium diboride and the titanium sponge were shown in Table 1.

(84) (2) Preparation of Consumable Electrode

(85) The powder mixture was pressed into a consumable electrode with a size of 300×60×60 mm by a 630-ton hydraulic press.

(86) (3) Melting

(87) The consumable electrode was subjected to vacuum melting twice to obtain a composite ingot with a diameter of 170 mm, where the element B was derived from the titanium diboride, and the element Ti was derived from the titanium sponge.

(88) (4) Preparation of a Titanium-Based Composite Bar

(89) The composite ingot was polished, heated to 1000-1050° C. in a high-temperature furnace and kept at 1000-1050° C. for 2 h. Then the composite ingot was subjected to billet forging using a 1-ton air hammer to obtain a bar A with a diameter of 100 mm. The bar A was polished and heated to 950° C. in the high-temperature furnace and kept at 950° C. for 2 h. The bar A was forged using a SKK-14 radial forging machine into a bar B with a diameter of 45 mm, and then the bar B was mechanically processed to produce a composite titanium-based bar C with a size of 41 mm×400 mm and a conical front end.

(90) (5) The composite titanium-based bar C was subjected to electrode induction melting ultrasonic gas atomization to prepare the boron-containing titanium-based composite powder.

(91) The boron-containing titanium-based composite powder obtained above was subjected to heat treatment at 1000° C. under an argon atmosphere using a Sparking Plasma Sintering (SPS) device and kept at 1000° C. for 15 min.