JPS63303043A - Manufacture of angle bar made of ti alloy - Google Patents

Abstract

PURPOSE:To manufacture an angle bar made of Ti alloy in which a pair of flanged parts are at right angles to each other, by heating a Ti alloy stock to a specific temp. and then rolling the above into a rectangular V shape by means of hot rolls. CONSTITUTION:Hot rolls 10 are constituted of the upper roll 12 having a rectangular V-shaped caliber 14 in the center and the lower roll 16 having a rectangular inverted V-shaped projecting part 18 in the center. A rolling stock composed of Ti alloy is heated to 1,000-1,100 deg.C and rolled by means of the above hot rolls 10 so as to be formed into an angle bar 20 in which a pair of flanged parts are at right angles to each other. By this method, the angle bar 20 made of Ti alloy of desired thickness can be manufactured by rolling.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for rolling a Ti alloy, and more particularly to a method for manufacturing an angle-shaped member made of a Ti alloy by hot hole rolling.

[Prior art] Ti alloys, especially α+β type Ti alloys, have a specific strength (tensile strength/
Because it has a high specific gravity) and excellent corrosion resistance, it is used in aircraft materials, space development equipment, etc. However, this α+β type T
Ti alloys, including i-alloys, generally have the disadvantage of high deformation resistance and extremely poor workability, and in addition, they must have a certain structure in order to impart the necessary ductility to the processed product.

That is, Ti-6A is a typical example of α+β type Ti alloy.
The I-4V alloy consists of two phases, α+β, at temperatures below about 1000°C, and becomes a single β phase at temperatures above that. Since deformation resistance is lower when processing is carried out at high temperatures, it is preferable to carry out hot working in the β-phase region. However, rolling or heating in the β-phase single-phase region at 1100°C or higher causes the temperature to be too high and the β crystal grains Coarsening occurs, and even if these coarse grains are subjected to annealing or solution heat treatment, coarse acicular crystals remain, resulting in a decrease in ductility. Although it is possible to obtain an equiaxed α+β structure through processing, processing in the α+β region has high deformation resistance, and due to temperature drop during rolling, too much α phase precipitates in the finish rolling temperature region, resulting in less elongation.

For these reasons, it has not been conventionally possible to manufacture Ti alloy shapes by rolling, and Ti alloys have poor cold formability, making it difficult to form them by bending. Therefore, extrusion molded products were manufactured by extrusion molding, but there were restrictions on the wall thickness of extrusion molded products, and thin walled products could not be manufactured.Therefore, it was hoped that a method of manufacturing Ti alloy shapes by rolling would emerge. It was rare.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned problems of the Ti alloy shaped material, and it is a method of manufacturing an angle shaped material of a desired wall thickness made of a Ti alloy by rolling. The purpose is to provide a manufacturing method that allows for

Means for Solving Problem L] The method for manufacturing a Ti alloy angle-shaped material of the present invention includes a step of heating a rolled material made of a Ti alloy to 1000 to 1100°C, and a hole having a right-angled V-shape in the center. A step of rolling the rolled material with a hot rolling roll consisting of a lower roll and an upper roll having a right-angled 8-shaped protrusion in the center, and forming an angle-shaped material so that the pair of flange parts are at right angles to each other. The gist is:

[Function] The rolled material is first heated to 1000 to 1100°C. The reason why the heating temperature of the rolled material was set to the above temperature is that if the temperature is 1000°C or less, the deformation resistance is large and rolling is difficult, and at the same time, the elongation of the rolled product after annealing becomes low. This is because if the value exceeds 100%, the ductility decreases due to the residual acicular β phase.

Next, the rolled material is rolled by hot rolling rolls consisting of a lower roll with a right-angled V-shaped hole in the center and an upper roll with a semicircular protrusion in the center, and is rolled into a pair of flanges having the same thickness as the product dimensions. rolled into parts. By this hot rolling, the rolled material is formed into an angle-shaped material such that the pair of flanges are perpendicular to each other.

[Embodiment] A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a side view of the hot rolling roll 10.

The hot rolling upper roll 12 is driven by a drive device (not shown), and is provided with a right-angled V-shaped hole 14 in the center. At the center of the hot iso-rolling lower roll 16, an eight-shaped protrusion 18 is provided at a position facing the hole 14 of the upper roll 12.

Introductionl! An alloy billet of 711 m and 50 bends and 1000 wheels in length was heated to 1050°C, and then this billet was successively rolled with rolling rolls (not shown) and then rolled with the final hot rolling roll 10 shown in FIG. 31 shown in Figure 2
An angle-shaped member 20 was formed so that a pair of thick flange portions were at right angles. Furthermore, when we examined the m-microscopic structure of the obtained chevron material 20, we found that it was an equiaxed α+β structure! It became clear that the necessary ductility was obtained.

[Effects of the Invention] As explained above, the method for manufacturing the Ti-metal angle shape material of the present invention involves rolling a rolled material made of Ti alloy to
℃ to perform hot rolling processing, and hot rolling is carried out by heating to a high temperature with low deformation resistance and at a temperature at which an equiaxed α-β structure can be obtained. The necessary ductility can be imparted to the finished product. In addition, hot rolling is performed using hot rolling rolls consisting of a lower roll having a right-angled V-shaped hole in the center and an upper roll having a right-angled eight-shaped convex strip in the center, so that the pair of flanges are at right angles to each other. This method forms an angle-shaped member, and it is possible to produce an angle-shaped member made of Ti alloy by rolling, which could not be obtained by conventional methods.

[Brief explanation of the drawing]

Fig. 1 is a side view of the hot rolling roll; Fig. 2 is a side view of the angle-shaped material; 10... hot rolling roll; 12... hot rolling upper roll; 14... hot rolling upper roll. 16... Hot rolling lower roll, 18... Convex strip of hot rolling lower roll,
20... Yamagata lumber.

Claims (1)

[Claims] (1) Rolled material made of Ti alloy with 1000 to 1100
℃, and rolling the rolled material with a hot rolling roll consisting of a lower roll having a right-angled V-shaped hole in the center and an upper roll having a right-angled Λ-shaped convex strip in the center, A method for manufacturing a Ti alloy angle-shaped member, characterized in that the angle-shaped member is formed so that a pair of flange portions are at right angles to each other.