CN101913022A - A method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials - Google Patents

Abstract

The invention discloses a method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials, which belongs to the field of fusion welding of dissimilar materials. It solves the problem that electron beam welding of dissimilar materials such as TA15 titanium alloy and chrome bronze is easy to produce intermetallic compound layered structure, and then leads to the problem of low tensile strength of welded joints. The welding object of the present invention is TA15 titanium alloy parent material and QCr0.8 chrome bronze alloy parent material, and the present invention adopts twice electron beam welding to finish welding, first adopts existing welding method to TA15 titanium alloy parent material and QCr0.8 chrome bronze The joints of the alloy base metal are welded, and then the focus position of the electron beam is moved to the side of the QCr0.8 chromium bronze alloy base metal by 0.2 mm to 1.0 mm for the second welding. The invention designs the focused welding position of the electron beam, and uses the superimposed welding method to improve the structure of the joint and reduce the adverse effects of intermetallic compounds. The invention is suitable for welding plates or pipes made of TA15 titanium alloy and QCr0.8 chrome bronze alloy.

Description

A method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials

technical field

The invention relates to an electron beam welding method for dissimilar materials of TA15 titanium alloy and QCr0.8 chrome bronze alloy, and belongs to the field of fusion welding of dissimilar materials.

Background technique

TA15 titanium alloy is an excellent structural material, which has the characteristics of low density, high specific strength, good plasticity and toughness, good heat and corrosion resistance, and good machinability. It is widely used in aviation, aerospace, vehicle engineering, biomedical engineering and other fields. It has very important application value. QCr0.8 chromium bronze alloy has excellent electrical and thermal conductivity, ductility and excellent corrosion resistance. Therefore, it has been widely used in industrial and military sectors such as electrical, electronic, chemical, power, transportation and aerospace.

The welding of dissimilar materials has been paid more and more attention by people. Its characteristic is that it can make full use of the respective advantages of materials to meet the various requirements of modern production on the structural properties of materials. In some cases, the comprehensive performance of dissimilar materials even exceeds that of a single metal structure. .

The effective connection of TA15 titanium alloy and QCr0.8 chrome bronze alloy dissimilar materials can not only meet the requirements of thermal conductivity, wear resistance and corrosion resistance, but also meet the requirements of light weight and high strength. It must be used in aerospace, shipbuilding, instrumentation and other fields It will have broad application prospects.

Using the existing electron beam welding method to realize the welding of TA15 titanium alloy and chrome bronze dissimilar materials, it is easy to form a layered structure composed of intermetallic compounds in the weld, which is the weak position in the joint. Reduces the tensile strength at the joint location of dissimilar materials. A reasonable method to solve this problem at home and abroad has not been reported yet.

Contents of the invention

The purpose of the present invention is to solve the problem that the electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials is easy to produce an intermetallic compound layered structure, thereby resulting in low tensile strength of the welded joint.

The method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials of the present invention, its welding object is TA15 titanium alloy base material and QCr0.8 chrome bronze alloy base material, described welding method adopts the method for welding twice to complete welding , the specific process is: after the welding of the weld seam is completed, the focus position of the electron beam is moved to the side of the QCr0.8 chromium bronze alloy base material by 0.2mm to 1.0mm, and the second welding is performed.

When the TA15 titanium alloy base material and the QCr0.8 chrome bronze alloy base material are plates with a thickness of 1.5 mm to 5.0 mm, the specific process of the welding method of the present invention is:

Step 1, pretreating the TA15 titanium alloy plate and the QCr0.8 chrome bronze alloy plate to be welded;

Step 2. Adjust the relative position of the TA15 titanium alloy plate and the QCr0.8 chrome bronze alloy plate so that the height difference between the butt joint surfaces of the two plates is less than 0.2mm, and the gap between the two butt joint surfaces is less than 0.1mm; then use The fixture is fixed to ensure that the relative position between the two plates remains unchanged;

Step 3. Put the two fixed plates obtained in Step 2 into a vacuum chamber, and evacuate the vacuum chamber so that the vacuum degree in the vacuum chamber is in the range of 5×10 ^-2 Pa to 5×10 ^-4 Pa;

Step 4. Focus the electron beam to the joint gap between the two plates, and start welding from one end of the gap to the other end; the working distance during welding is 150mm, the accelerating voltage is 55kV, the focusing current is 2590mA, and the electron beam current is 15mA～50mA, welding speed is 4mm/s～12mm/s;

Step 5. Move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy plate by 0.2mm to 1.0mm, and then start the second welding. The welding trajectory this time is parallel to the welding trajectory in step 4. The accelerating voltage is 55kV, the focusing current is 2590mA, the electron beam current is 12mA~45mA, and the welding speed is 5mm/s~12mm/s;

Step 6. Cool the vacuum chamber for 8 minutes to 12 minutes, then remove the vacuum and take out the welded test piece, and the welding is completed.

When both the TA15 titanium alloy base material and the QCr0.8 chrome bronze alloy base material are pipes with a wall thickness of 1.5 mm to 5.0 mm, the welded seam is an annular butt weld, and the process of the welding method of the present invention for:

Step 1, pretreatment of the TA15 titanium alloy pipe to be welded and the QCr0.8 chrome-bronze alloy pipe;

Step 2. Adjust the relative position of the two pipes so that the misalignment of the butt surfaces of the two pipes is less than 0.2mm, and the gap between the two butt surfaces is less than 0.1mm, and then fix it with a clamp so that the gap between the two pipes The relative position remains unchanged;

Step 3. Put the fixed two pipes into the vacuum chamber and pump the vacuum so that the vacuum degree in the vacuum chamber is between 5×10 ^-2 Pa and 5×10 ^-4 Pa;

Step 4. Focus the electron beam to the butt joint of the two pipes and start welding. The working distance during welding is 150mm, the accelerating voltage is 55kV, the focusing current is 2590mA, the electron beam current is 15mA-50mA, and the welding speed is 5mm/ s～12mm/s, the welding stroke is 450 degrees;

Step 5. Move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy pipe fitting by 0.2mm to 1.0mm, and then start the second welding. The welding trajectory this time is parallel to the welding trajectory in step 4. Accelerate during welding The voltage is 55kV, the focusing current is 2590mA, the electron beam current is 12mA~45mA, the welding speed is 5mm/s~12mm/s, and the welding stroke is 450 degrees;

Step 6. Cool the vacuum chamber for 8 minutes to 12 minutes, then remove the vacuum and take out the welded test piece, and the welding is completed.

The TA15 titanium alloy composition of the present invention is Al: 5.5～7.0% (weight), V: 0.8～2.5% (weight), Zr: 1.5～2.5% (weight), Mo: 0.5～2.0% (weight), The balance is Ti; the composition of the QCr0.8 chromium bronze alloy is Cr: 0.4-0.7% (weight), impurity ≤ 0.8% (weight), and the balance is Cu.

The welded joint strength between TA15 titanium alloy and QCr0.8 chromium bronze alloy by conventional electron beam welding method is low, only about 40% of that of QCr0.8 chromium bronze alloy base metal. The difference between the present invention and the conventional welding method is that the overlapping welding method is used to carry out electron beam welding on the butt joint surface of the TA15 titanium alloy and the QCr0.8 chromium bronze alloy, and the side of the QCr0.8 chromium bronze alloy at a certain distance. On the one hand, it can form a good metallurgical bond between the TA15 titanium alloy and the QCr0.8 chrome bronze alloy weld, and the joint has no welding defects such as pores and cracks; The compound lamellar structure is weakened or even eliminated, and a continuously distributed weld structure can be obtained, so that the tensile strength of the joint can be increased to more than 70% of the QCr0.8 chromium bronze alloy base material, and a high-quality and high-strength joint can be obtained.

Detailed ways

Specific embodiment one: a kind of electron beam welding method of TA15 titanium alloy and chromium bronze dissimilar material described in this embodiment, its welding object is TA15 titanium alloy base material and QCr0.8 chrome bronze alloy base material, described welding method In order to complete the welding by two welding methods, the specific process is as follows: after welding the weld seam, move the electron beam focus position to the side of the QCr0.8 chrome bronze alloy base metal by 0.2mm to 1.0mm, and perform the second welding , the composition of the TA15 titanium alloy described in this embodiment is Al: 5.5-7.0% (weight), V: 0.8-2.5% (weight), Zr: 1.5-2.5% (weight), Mo: 0.5-2.0% (weight ), the balance is Ti; the composition of the QCr0.8 chromium bronze alloy is Cr: 0.4-0.7% (weight), impurities≤0.8% (weight), and the balance is Cu.

In this embodiment, by designing the focused welding position of the electron beam, the superimposed welding method is used to improve the structure of the joint, reduce or eliminate the adverse effects of intermetallic compounds, and obtain a high-quality and high-strength joint.

Specific embodiment two: a specific embodiment of the method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials described in this embodiment and specific embodiment one, the TA15 titanium alloy base material and QCr0. 8 The base metal of chrome bronze alloy is a plate with a thickness of 1.5mm to 5.0mm. The specific welding method is:

Step 1, pretreating the TA15 titanium alloy plate and the QCr0.8 chrome bronze alloy plate to be welded;

Step 2. Adjust the relative position of the TA15 titanium alloy plate and the QCr0.8 chrome bronze alloy plate so that the height difference between the butt joint surfaces of the two plates is less than 0.2mm, and the gap between the two butt joint surfaces is less than 0.1mm; then use The fixture is fixed to ensure that the relative position between the two plates remains unchanged, and then step 3 is performed;

Step 3. Put the two fixed plates obtained in Step 2 into a vacuum chamber, and evacuate the vacuum chamber so that the vacuum degree in the vacuum chamber is in the range of 5×10 ^-2 Pa to 5×10 ^-4 Pa;

Step 4. Focus the electron beam to the joint gap between the two plates, and start welding from one end of the gap to the other end; the working distance during welding is 150mm, the accelerating voltage is 55kV, the focusing current is 2590mA, and the electron beam current is 15mA～50mA, welding speed is 4mm/s～12mm/s;

Step 5. Move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy plate by 0.2mm to 1.0mm, and then start the second welding. The welding trajectory this time is parallel to the welding trajectory in step 4. The accelerating voltage is 55kV, the focusing current is 2590mA, the electron beam current is 12mA~45mA, and the welding speed is 5mm/s~12mm/s;

Step 6. Cool the vacuum chamber for 8 minutes to 12 minutes, then remove the vacuum and take out the welded test piece, and the welding is completed.

Embodiment 3: The difference between this embodiment and the method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 2 is that the pretreatment in step 1 includes mechanical grinding and chemical cleaning.

Embodiment 4: The difference between this embodiment and the method of electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 2 is that the fixing method described in Step 2 adopts the upper surface loading method . Specifically, pressure can be applied to the end points of the two ends of the two plates to ensure that the test piece does not move during the welding process.

Embodiment 5: The difference between this embodiment and the method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 2 is that the vacuum degree in the vacuum chamber described in step 3 is at 5×10 ^-3 Pa to 5×10 ^-4 Pa.

Embodiment 6: The difference between this embodiment and the method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 2 is that the thickness of the welding object is 1.5 mm to 3.0 mm. in the process,

In step 4, the electron beam current is 15mA-30mA, and the welding speed is 8mm/s-12mm/s;

In step five, move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy plate by 0.2mm~0.6mm, and then start the second welding. The electron beam current for this welding is 12mA~25mA, and the welding speed is 8mm /s～12mm/s.

Embodiment 7: The difference between this embodiment and the method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 2 is that the thickness of the welding object is 3.5 mm to 5.0 mm. In process:

In step 4, the electron beam current is 30mA-50mA, and the welding speed is 5mm/s-8mm/s;

In step five, move the focus position of the electron beam to the QCr0.8 chrome bronze alloy plate by 0.6~1.0mm, and then start the second welding. The electron beam current for this welding is 25mA~45mA, and the welding speed is 5mm/s~ 8mm/s.

Embodiment 8: This embodiment is a specific embodiment of a method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 1. The TA15 titanium alloy base material and QCr0. 8 The chromium bronze alloy parent material is a pipe with a wall thickness of 1.5mm to 5.0mm, and the welded seam is a circular butt weld. The specific steps are:

Step 1, pretreatment of the TA15 titanium alloy pipe to be welded and the QCr0.8 chrome-bronze alloy pipe;

Step 2. Adjust the relative position of the two pipes so that the misalignment of the butt surfaces of the two pipes is less than 0.2mm, and the gap between the two butt surfaces is less than 0.1mm, and then fix it with a clamp so that the gap between the two pipes The relative position remains unchanged;

Step 3. Put the fixed two pipes into the vacuum chamber and pump the vacuum so that the vacuum degree in the vacuum chamber is between 5×10 ^-2 Pa and 5×10 ^-4 Pa;

Step 4. Focus the electron beam to the butt joint of the two pipes and start welding. The working distance during welding is 150mm, the accelerating voltage is 55kV, the focusing current is 2590mA, the electron beam current is 15mA-50mA, and the welding speed is 5mm/ s～12mm/s, the welding stroke is 450 degrees;

Step 5. Move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy pipe fitting by 0.2-1.0mm, and then start the second welding. The welding trajectory of this time is parallel to the welding trajectory in step 4. Accelerate the voltage during welding 55kV, focusing current 2590mA, electron beam current 12mA~45mA, welding speed 5mm/s~12mm/s, welding stroke 450 degrees;

Step 6. Cool the vacuum chamber for 8 minutes to 12 minutes, then remove the vacuum and take out the welded test piece, and the welding is completed.

Embodiment 9: The difference between this embodiment and the method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 8 is that the pretreatment in step 1 includes mechanical grinding and chemical cleaning.

Embodiment 10: The difference between this embodiment and the method of electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 8 is that the fixing method described in step 2 adopts the method of uniform loading at both ends. Way. Specifically, pressure can be applied to both ends of the two pipe fittings to ensure that the test piece does not move during the welding process.

Embodiment 11: The difference between this embodiment and the method of electron beam welding TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 8 is that the vacuum degree in the vacuum chamber described in step 3 is at 5× 10 ^-3 Pa to 5×10 ^-4 Pa.

Embodiment 12: The difference between this embodiment and the method of electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 8 is that the wall thickness of the welding object is 1.5 mm to 3.0 mm, During welding:

In step 4, the electron beam current is 15mA-30mA, and the welding speed is 8mm/s-12mm/s;

In step 5, move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy pipe fitting by 0.2mm~0.6mm, and then start the second welding. The electron beam current in this welding is 12mA~25mA, and the welding speed is 8mm/s～12mm/s.

Embodiment 13: The difference between this embodiment and the method of electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials described in Embodiment 8 is that the wall thickness of the welding object is 3.0 mm to 5.0 mm, During welding:

In step 4, the electron beam current is 30mA-50mA, and the welding speed is 5mm/s-8mm/s;

In step five, move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy pipe by 0.6mm~1.0mm, and then start the second welding. The electron beam current in this welding is 25mA~45mA, and the welding speed is 5mm /s～8mm/s.

Claims (10)

1. A method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials, its welding object is TA15 titanium alloy base material and QCr0.8 chromium bronze alloy base material, and the welding seam is welded by electron beam welding method, its characteristics That is, the welding method uses two welding methods to complete the welding, and the specific process is: after the welding seam is completed, the electron beam focus position is moved to the side of the QCr0.8 chromium bronze alloy base material by 0.2 mm to 1.0 mm, Carry out welding for the second time, described TA15 titanium alloy composition is Al: 5.5～7.0% (weight), V: 0.8～2.5% (weight), Zr: 1.5～2.5% (weight), Mo: 0.5～2.0% (weight), the balance is Ti; the composition of QCr0.8 chrome bronze alloy is Cr: 0.4-0.7% (weight), impurity≤0.8% (weight), and the balance is Cu. 2. the method for a kind of electron beam welding TA15 titanium alloy and chrome bronze dissimilar material according to claim 1, it is characterized in that, described TA15 titanium alloy base material and QCr0.8 chromium bronze alloy base material are thickness 1.5 mm ~ 5.0mm plate, the specific welding process is: Step 1, pretreating the TA15 titanium alloy plate and the QCr0.8 chrome bronze alloy plate to be welded; Step 2. Adjust the relative position of the TA15 titanium alloy plate and the QCr0.8 chrome bronze alloy plate, so that the misalignment of the butt joint surfaces of the two plates is less than 0.2mm, and the gap between the two butt joint surfaces is less than 0.1mm; then use The fixture fixes the two plates so that the relative position between the two plates remains unchanged; Step 3. Put the two fixed plates obtained in Step 2 into a vacuum chamber, and evacuate the vacuum chamber so that the vacuum degree in the vacuum chamber is within the range of 5×10 ^-2 Pa to 5×10 ^-4 Pa; Step 4. Focus the electron beam to the joint gap between the two plates, and start welding from one end of the gap to the other end; the working distance during welding is 150mm, the accelerating voltage is 55kV, the focusing current is 2590mA, and the electron beam current is 15mA～50mA, welding speed is 4mm/s～12mm/s; Step 5. Move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy plate by 0.2mm to 1.0mm, and then start the second welding. The welding trajectory this time is parallel to the welding trajectory in step 4. The accelerating voltage is 55kV, the focusing current is 2590mA, the electron beam current is 12mA~45mA, and the welding speed is 5mm/s~12mm/s; Step 6. Cool the vacuum chamber for 8 minutes to 12 minutes, then remove the vacuum and take out the welded test piece, and the welding is completed. 3. A method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials according to claim 2, wherein the pretreatment in step 1 includes mechanical grinding and chemical cleaning. 4. A method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials according to claim 2, characterized in that the fixing method described in step 2 is the upper surface loading method. 5. A method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials according to claim 2, wherein the welding object is a TA15 titanium alloy plate with a thickness of 1.5 mm to 3.0 mm and QCr0.8 Chrome bronze alloy sheet, during welding, In step 4, the electron beam current is 15mA-30mA, and the welding speed is 8mm/s-12mm/s; In step five, move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy plate by 0.2mm~0.6mm, and then start the second welding. The electron beam current for this welding is 12mA~25mA, and the welding speed is 8mm /s～12mm/s. 6. A method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials according to claim 2, wherein the welding object is a TA15 titanium alloy plate with a thickness of 3.5 mm to 5.0 mm and QCr0.8 Chromium bronze alloy plates, during welding: In step 4, the electron beam current is 30mA-50mA, and the welding speed is 5mm/s-8mm/s; In step five, move the focus position of the electron beam to the QCr0.8 chrome bronze alloy plate by 0.6mm~1.0mm, and then start the second welding. The electron beam current for this welding is 25mA~45mA, and the welding speed is 5mm/s ~8mm/s. 7. the method for a kind of electron beam welding TA15 titanium alloy and chrome bronze dissimilar material according to claim 1, it is characterized in that, described TA15 titanium alloy base material and QCr0.8 chromium bronze alloy base material are two wall thicknesses For pipes of 1.5mm to 5.0mm, the welded seam is a circular butt weld, and the specific steps are: Step 1, pretreatment of the TA15 titanium alloy pipe to be welded and the QCr0.8 chrome-bronze alloy pipe; Step 2. Adjust the relative position of the two pipes so that the height difference between the butt joint surfaces of the two pipes is less than 0.2mm, and the gap between the two butt joint surfaces is less than 0.1mm, and then fix it with a clamp so that the gap between the two pipes is less than 0.2 mm. The relative position remains unchanged; Step 3. Put the fixed two pipes into the vacuum chamber and pump the vacuum so that the vacuum degree in the vacuum chamber is between 5×10 ^-2 Pa and 5×10 ^-4 Pa; Step 4. Focus the electron beam to the butt joint of the two pipes and start welding. The working distance during welding is 150mm, the accelerating voltage is 55kV, the focusing current is 2590mA, the electron beam current is 15mA-50mA, and the welding speed is 5mm/ s～12mm/s, the welding stroke is 450 degrees; Step 5. Move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy pipe fitting by 0.2mm to 1.0mm, and then start the second welding. The welding trajectory this time is parallel to the welding trajectory in step 4. Accelerate during welding The voltage is 55kV, the focusing current is 2590mA, the electron beam current is 12mA~45mA, the welding speed is 5mm/s~12mm/s, and the welding stroke is 450 degrees; Step 6. Cool the vacuum chamber for 8 minutes to 12 minutes, then remove the vacuum and take out the welded test piece, and the welding is completed. 8. A method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials according to claim 7, characterized in that the fixing method described in step 2 adopts the method of uniform loading at both ends. 9. A method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials according to claim 7, wherein the welding object is a TA15 titanium alloy pipe with a wall thickness of 1.5mm to 3.0mm and QCr0. 8 chrome bronze alloy pipes, during welding: In step 4, the electron beam current is 15mA-30mA, and the welding speed is 8mm/s-12mm/s; In step 5, move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy pipe fitting by 0.2mm~0.6mm, and then start the second welding. The electron beam current in this welding is 12mA~25mA, and the welding speed is 8mm/s～12mm/s. 10. A method for electron beam welding of TA15 titanium alloy and chrome bronze dissimilar materials according to claim 7, wherein the welding objects are two TA15 titanium alloy pipes with a wall thickness of 3.0 mm to 5.0 mm and QCr0.8 chrome-bronze alloy pipes, during the welding process: In step 4, the electron beam current is 30mA-50mA, and the welding speed is 5mm/s-8mm/s; In step five, move the focus position of the electron beam to the side of the QCr0.8 chrome bronze alloy pipe by 0.6mm~1.0mm, and then start the second welding. The electron beam current in this welding is 25mA~45mA, and the welding speed is 5mm /s～8mm/s.