阅读说明：本技术 一种热塑性复合材料与轻质合金超声辅助激光连接工艺 (Ultrasonic-assisted laser connection process for thermoplastic composite material and light alloy ) 是由 占小红 杨红艳 王磊磊 于 2020-05-13 设计创作，主要内容包括：本发明公开一种热塑性复合材料与轻质合金超声辅助激光连接工艺,所述轻质合金表面加工出均匀分布的倒三角形状凹槽,热塑性复合材料与轻质合金连接界面填充热塑性树脂粉末,所述超声辅助焊接中采用“热塑性复材-树脂粉末-轻质合金”搭接方式,轻质合金置于下层,所述激光焊接将轻质合金置于上层,所述热塑性复合材料与轻质合金超声辅助激光连接工艺包括如下步骤：1)清洁处理,轻质合金表面凹槽加工处理；2)界面处铺置粉末后固定,进行超声波第一次焊接；3)翻转连接件重新固定后进行激光第二次焊接。本发明能够有效改善热塑性复合材料与轻质合金连接界面熔合质量,提高拉剪强度和疲劳性能。(The invention discloses an ultrasonic-assisted laser connecting process for a thermoplastic composite material and a light alloy, wherein the surface of the light alloy is processed with uniformly distributed inverted triangular grooves, the connecting interface of the thermoplastic composite material and the light alloy is filled with thermoplastic resin powder, the ultrasonic-assisted welding adopts a 'thermoplastic composite material-resin powder-light alloy' lap joint mode, the light alloy is arranged at the lower layer, the laser welding is used for arranging the light alloy at the upper layer, and the ultrasonic-assisted laser connecting process for the thermoplastic composite material and the light alloy comprises the following steps: 1) cleaning, namely processing grooves on the surface of the light alloy; 2) powder is laid on the interface and then fixed, and ultrasonic first welding is carried out; 3) and after the turnover connecting piece is fixed again, performing laser second welding. The invention can effectively improve the fusion quality of the connection interface of the thermoplastic composite material and the light alloy, and improve the tensile-shear strength and the fatigue performance.)

1. The ultrasonic-assisted laser connection process for the thermoplastic composite material and the light alloy is characterized by mainly comprising the following steps of performing ultrasonic first welding and laser second welding, processing uniformly-distributed inverted triangular grooves on the surface of the light alloy, filling thermoplastic resin powder in a connection interface of the thermoplastic composite material and the light alloy, wherein the ultrasonic first welding adopts a lap joint mode of thermoplastic composite material-resin powder-light alloy, the light alloy is arranged on a lower layer, and the laser second welding is used for arranging the light alloy on an upper layer, and the ultrasonic-assisted laser connection process for the thermoplastic composite material and the light alloy comprises the following steps of:

(1) firstly, cleaning a thermoplastic composite material and a light alloy, and processing a groove on the surface of the light alloy;

(2) after resin powder is laid on a connecting interface of the thermoplastic composite material and the light alloy, in order to fully fill the grooves on the surface of the light alloy with the resin powder, connecting pieces to be connected are fixed on an ultrasonic auxiliary welding base after being overlapped according to the sequence of thermoplastic composite material, resin powder and light alloy, and ultrasonic first-time welding is carried out;

(3) and (3) turning the primarily connected thermoplastic composite material and the lightweight alloy lap joint part in the direction to enable the lightweight alloy to be arranged above the preliminarily connected thermoplastic composite material and the lightweight alloy lap joint part, and re-fixing the lightweight alloy on the laser welding base for secondary laser welding.

2. The ultrasonic-assisted laser connection process for the thermoplastic composite material and the light alloy is characterized in that in the first ultrasonic welding process, a tool head and a base apply longitudinal pressure on a to-be-connected piece, so that filling resin is fully combined with the thermoplastic composite material and the light alloy after being heated and melted.

3. The ultrasonic-assisted laser connection process for the thermoplastic composite material and the light alloy is characterized in that the laser motion mode in the second laser welding process is forward circular oscillation.

4. The ultrasonic-assisted laser connection process for the thermoplastic composite material and the light alloy is characterized in that the type of the interface filling resin is thermoplastic composite material matrix resin.

5. The ultrasonic-assisted laser connection process for the thermoplastic composite material and the light alloy is characterized in that cleaning treatment before welding comprises the steps of carrying out acid washing or alkali washing on the light alloy to remove a surface oxide film, and carrying out ultrasonic cleaning on the thermoplastic composite material by using acetone.

Technical Field

The invention relates to an ultrasonic-assisted laser connection process, in particular to an ultrasonic-assisted laser connection process for a super-thermoplastic composite material and a light alloy, and belongs to the field of dissimilar material connection.

Background

The thermoplastic composite material has wide application prospect in the fields of aerospace manufacturing, automobiles and the like due to the characteristics of high specific strength, corrosion resistance, fatigue resistance, high temperature resistance and the like as an important lightweight manufacturing material. The light alloy material can meet the design concept of light weight, can meet the mechanical property of core components, and has an important position in the fields of aerocrafts and the like. Therefore, in practical production application, the thermoplastic composite material and the light alloy are often required to be connected, the thermoplastic composite material and the light alloy are directly connected by laser welding, and the problems of poor interface fusion appearance, more fusion defects, low connection strength and the like exist. Ultrasonic welding is to contact interface materials by using high-frequency vibration, and further generate plastic flow and diffusion under the combined action of friction and ultrasonic softening to enlarge the connection area, and finally form reliable connection. Laser welding is an efficient and precise welding method using a laser beam with high energy density as a heat source, and a welded joint with good forming and stable performance is obtained by controlling parameters such as the width, energy, peak power, repetition frequency and the like of laser pulses. The invention relates to an ultrasonic-assisted laser connection process of a thermoplastic composite material and a light alloy, which is characterized in that resin powder filled in an interface is melted by ultrasonic-assisted welding, the thermoplastic composite material and the light alloy are primarily connected through molten resin, and then a stable dissimilar material connection joint is formed at the lap joint of the thermoplastic composite material and the light alloy through laser welding, so that the fusion quality of the connection interface of the thermoplastic composite material and the light alloy is effectively improved, and the tensile-shear strength and the fatigue performance of the connection joint of the thermoplastic composite material and the light alloy are improved.

Disclosure of Invention

In order to solve the problem of connection between the thermoplastic composite material and the light alloy and obtain a high-strength connection joint, the invention provides an ultrasonic-assisted laser connection process for the thermoplastic composite material and the light alloy, which can effectively improve the fusion quality of a connection interface between the thermoplastic composite material and the light alloy and improve the tensile-shear strength and fatigue performance of a connection structure between the thermoplastic composite material and the light alloy.

The invention adopts the following technical scheme: the ultrasonic-assisted laser connecting process of the thermoplastic composite material and the light alloy comprises the following steps of: (1) firstly, cleaning a thermoplastic composite material and a light alloy, and processing a groove on the surface of the light alloy; (2) after resin powder is laid at the connecting interface of the thermoplastic composite material and the light alloy, a to-be-connected piece is fixed on an ultrasonic auxiliary welding base after being lapped according to the sequence of the thermoplastic composite material, the resin powder and the light alloy, and ultrasonic first-time welding is carried out; (3) and (3) turning the primarily connected plastic composite material and the lightweight alloy lap joint part in the direction to enable the lightweight alloy to be arranged above the plastic composite material and the lightweight alloy lap joint part, re-fixing the lightweight alloy on the laser welding base, and carrying out laser secondary welding. The thickness of the thermoplastic composite material is suitable for 2-8 mm, the thickness of the light alloy is suitable for 2-4 mm, the surface of the light alloy is processed into uniformly distributed inverted triangular grooves, the width of each groove is 0.5mm, the depth of each groove is 0.35mm, and the distribution density range of the grooves is 30% -50%. Thermoplastic resin powder is filled in the connection interface of the thermoplastic composite material and the light alloy, the type of the filled resin is thermoplastic composite material matrix resin, the filling thickness of the resin powder is 0.1-0.3 mm, and the resin powder fills the grooves of the light alloy. The first ultrasonic welding adopts a lap joint mode of thermoplastic composite material-resin powder-light alloy, the light alloy is arranged on the lower layer, the first ultrasonic welding power is 300-600W, the ultrasonic frequency is 10-30 kHz, the tool head applies longitudinal pressure to the to-be-connected piece, the pressure value is 0.1-0.2 MPa, and the welding time is 10-15 s. The light alloy is placed on the upper layer in the second laser welding, the welding power is 1000-2000W, the welding path is linear, the laser movement mode is forward circular swing, and the swing amplitude is 2 mm. The cleaning treatment before welding comprises the steps of carrying out acid washing or alkali washing on the light alloy to remove a surface oxidation film, and carrying out ultrasonic cleaning on the thermoplastic composite material by utilizing acetone.

The invention has the following beneficial effects: the ultrasonic-assisted laser connection process for the thermoplastic composite material and the light alloy innovatively realizes the combination of ultrasonic welding and laser welding for connecting the thermoplastic composite material and the light alloy, effectively improves the fusion quality of the connection interface of the thermoplastic composite material and the light alloy, and improves the tensile-shear strength and fatigue performance of the connection joint of the thermoplastic composite material and the light alloy.

Drawings

FIG. 1 is a schematic view of an ultrasonic-assisted laser joining process of a thermoplastic composite material and a light alloy.

Wherein:

1-controller, 2-generator, 3-transducer, 4-amplitude transformer, 5-tool head, 6-base, 7-thermoplastic composite material, 8-light alloy, 9-filling resin powder, 10-laser head, 11-workbench.

Detailed Description

Referring to fig. 1, the ultrasonic-assisted laser connection process for thermoplastic composite materials and light alloys of the present invention includes a controller 1, a generator 2, a transducer 3, a horn 4, a tool head 5, a base 6, thermoplastic composite materials 7, light alloys 8, filling resin powder 9, a laser head 10, and a worktable 11.

Preferably, the thickness of the thermoplastic composite material 7 is suitable for 2-8 mm, the thickness of the light alloy 8 is suitable for 2-4 mm, the surface of the light alloy 8 is processed with uniformly distributed inverted triangular grooves, the width of each groove is 0.5mm, the depth of each groove is 0.35mm, and the distribution density range of the grooves is 30% -50%. Thermoplastic resin powder 9 is filled in the connecting interface of the thermoplastic composite material 7 and the light alloy 8, the type of the filled resin is thermoplastic composite material 7 matrix resin, the filling thickness of the resin powder 9 is 0.1-0.3 mm, and the grooves of the light alloy 8 are filled. The first ultrasonic welding is carried out in a lap joint mode of 'thermoplastic composite material 7-resin powder 9-light alloy 8', the light alloy 8 is arranged on the lower layer, the welding power is 300-600W, the ultrasonic frequency is 10-30 kHz, the tool head 5 applies longitudinal pressure to a to-be-connected piece, the pressure value is 0.1-0.2 MPa, and the welding time is 10-15 s. The light alloy 8 is placed on the upper layer in the second laser welding, the welding power is 1000-2000W, the welding path is linear, the laser motion mode is forward circular swing, and the swing amplitude is 2 mm. The cleaning treatment before welding comprises the steps of carrying out acid washing or alkali washing on the light alloy 8 to remove a surface oxidation film, and carrying out ultrasonic cleaning on the thermoplastic composite material 7 by utilizing acetone.

Specifically, the laser connection of the ultrasonic-assisted thermoplastic composite material 7 and the light alloy 8 comprises the following specific implementation steps: firstly, respectively cleaning the thermoplastic composite material 7 and the light alloy 8, and processing the groove on the surface of the light alloy 8. Secondly, resin powder 9 is laid on the connecting interface of the thermoplastic composite material 7 and the light alloy 8, a to-be-connected piece is fixed on the ultrasonic auxiliary welding base 6 after being lapped according to the sequence of the thermoplastic composite material 7, the resin powder 9 and the light alloy 8, and ultrasonic first-time welding is carried out: the switch of the controller 1 is started, the generator 2 generates a high-frequency electric signal and transmits the high-frequency electric signal to the transducer 3, the transducer 3 converts the high-frequency electric signal into an ultrasonic vibration signal, and the high-frequency vibration is transmitted to a connecting joint of the thermoplastic composite material 7 and the light alloy 8 through the oscillating rod 4 and the welding tool head 5, so that the parts to be welded are connected preliminarily. Finally, the lapping part which is primarily connected with the plastic composite material 7 and the light alloy 8 is turned over, so that the light alloy 8 is arranged above and is fixed on the laser welding workbench 11 again, the laser head 10 emits laser which irradiates the surface of the light alloy 8 of the joint of the part to be welded for secondary welding by the laser until the welding is finished.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the invention and are not to be construed as limitations of the embodiments of the present invention, and that modifications in the detailed description and applications of the invention may be made by those skilled in the art according to the spirit of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.