RU228598U1 - Friction stir welding tool for aluminum alloys - Google Patents

Abstract

The utility model relates to tools intended for friction stir welding of aluminum alloys. The tool for friction stir welding of aluminum alloys is made of die tool steel and is a monolithic structure consisting of a cylinder on which a chamfer is milled, a shoulder along the entire surface of which a single-start spiral with a depth of 1 mm and a pitch of 2.5 mm is made, and a rod extending from the shoulder having a thread made three-start with a right pitch of 9 mm and, in addition, a single-start thread with a pitch of 1.5 mm is made on the rod, wherein the diameter of the shoulder is equal to two diameters of the rod, and the height has a size less than the thickness of the welded material by 0.1-0.2 mm. A reduction in the metal consumption of the material used to manufacture the tool is ensured. 2 figs., 1 table.

Description

The utility model relates to tools intended for friction stir welding of aluminum alloys.

A fracture-resistant friction stir welding tool is known from the prior art [RU 2466838 C2, IPC B23K 20/12, published 2012.11.20], which comprises a body, a pin, a tensile element and an end assembly. The tensile element and the end assembly provide axial compression of the pin. The tensile element can be disconnected from the pin and/or body using one or more disconnecting elements. The end assembly may contain spring elements for applying an axial force to the tensile element. The pin may include various means for providing stress reduction near the pin.

The disadvantages of the tool are the complexity and, accordingly, the cost of production. This design is more suitable for welding thick materials.

The closest analogue - prototype - is a friction stir welding (FSW) tool [RU 2417143 C2, IPC B23K 20/12, published 2011.04.27], which includes a shoulder and a threaded rod extending from it. The rod (6) contains at least three adjacent sections, uniformly distributed around the longitudinal axis of the rod and having a generally convex shape. Each section contains at least three adjacent, mainly flat parts, the normals to which converge in the direction of the rod axis. Threaded parts are located between each pair of adjacent sections.

The disadvantages of the tool are its complexity and, accordingly, the cost of production.

The technical effect that the claimed utility model is aimed at achieving is to reduce the metal consumption of the material used to manufacture the tool, which reduces the final cost of the tool.

The technical effect is achieved due to the fact that the tool for friction stir welding of aluminum alloys is made of die tool steel and is a monolithic structure consisting of a cylinder on which a chamfer is milled, a shoulder along the entire surface of which a single-start spiral with a depth of 1 mm and a pitch of 2.5 mm is made, and a rod extending from the shoulder, having a thread made three-start with a right pitch of 9 mm and, in addition, a single-start thread with a pitch of 1.5 mm is made on the rod, while the diameter of the shoulder is equal to two diameters of the rod, and the height has a size less than the thickness of the material being welded by 0.1-0.2 mm.

The essence of the claimed utility model is explained by the following figures:

Fig. 1 - drawing of the geometry of the friction stir welding tool, where

1 - cylinder

2 - bald spot

3 - rod

4 - shoulder

5 - spiral

6 - 3-start (three-start) thread on the rod

7 - single-start thread.

Fig. 2 - photo of the instrument.

The tool consists of (in Fig. 1): cylinder 1, made with chamfer 2, shoulder 4 and rod 3.

The technical result is given in "Manufacturing technology". The STP tool of this geometry is manufactured on a turning and milling machining center, in one setup, according to the control program. Three tools are used: a turning cutter with a plate angle of 55 degrees, a turning cutter with a plate angle of 30 degrees, and a radius cutter R1.

The tool according to the utility model (Fig. 1, Fig. 2) is made of die tool steel and includes a cylinder (1) with a chamfer (2) made on it for fixing in the machine spindle and transmitting rotation, as well as a shoulder (4) with a diameter D, intended for local heating and connected to the cylinder, while a single-start spiral (5) with a depth of 1 mm is made on the shoulder (4), along the entire surface. A rod (3) with a diameter d and a height h is turned from the shoulder (4), intended for mixing the joint, and on which a three-start thread (6) with a right-hand pitch of 9 mm is made, while the height of the rod is made less than the thickness of the welded material by 0.1-0.2 mm, in order to exclude incomplete fusion at the root of the weld, in addition, a single-start thread (7) with a pitch of 1.5 mm is cut on the rod for better mixing. As a rule, D=2d.

The tool works as follows: when the tool rotates, the rod (3) begins to penetrate into the welded metal, to the depth of the sheet thickness. When the shoulder (4) touches the sheet surface, local heating begins in the friction zone of the tool. After the start of movement along the joint, the plasticized metal moves away in the direction opposite to the movement, thereby creating a welded joint. The standard size of the tool is given in Table 1.

The main welding parameters are: tool rotation frequency (rpm), axial welding force (kgf) and welding speed along the joint (mm/min). Experimental work was carried out on FSW welding of aluminum alloys of the 5th group with a thickness of 4 mm and 5 mm. Optimum modes: F = 2500 kgf, n = 550 rpm, f = 500 mm/min. The strength and plasticity of the weld are higher than the base metal. For the specified thicknesses, a 3-start thread allows increasing the welding speed by 1.5-2 times, while maintaining quality.

This utility model can be used for friction stir welding of aluminum alloys in the thickness range of 3 mm, 4 mm, 5 mm and 6 mm for butt and overlap welds.

The proposed utility model, due to its design, will allow for a reduction in the metal consumption of the material used to manufacture the tool.

Claims (1)

A tool for friction stir welding of aluminum alloys, comprising a cylinder, a shoulder and a threaded rod extending from it, characterized in that the tool is made of die tool steel, is a monolithic structure, the cylinder is made with a chamfer, along the entire surface of the shoulder there is a single-start spiral with a depth of 1 mm and a pitch of 2.5 mm, a rod extends from the shoulder, having a thread made three-start with a right pitch of 9 mm, in addition, a single-start thread is cut on the rod with a pitch of 1.5 mm, wherein the shoulder diameter is equal to two diameters of the rod, and the height has a size less than the thickness of the material being welded by 0.1-0.2 mm.